fix ax201 pci config #3
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Recent changes exposed a bug where specifically-timed requests to the path manager netlink API could trigger a divide-by-zero in __tcp_select_window(), as syzkaller does: divide error: 0000 [#1] SMP KASAN NOPTI CPU: 0 PID: 9667 Comm: syz-executor.0 Not tainted 5.14.0-rc6+ #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 RIP: 0010:__tcp_select_window+0x509/0xa60 net/ipv4/tcp_output.c:3016 Code: 44 89 ff e8 c9 29 e9 fd 45 39 e7 0f 8d 20 ff ff ff e8 db 28 e9 fd 44 89 e3 e9 13 ff ff ff e8 ce 28 e9 fd 44 89 e0 44 89 e3 99 <f7> 7c 24 04 29 d3 e9 fc fe ff ff e8 b7 28 e9 fd 44 89 f1 48 89 ea RSP: 0018:ffff888031ccf020 EFLAGS: 00010216 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000040000 RDX: 0000000000000000 RSI: ffff88811532c080 RDI: 0000000000000002 RBP: 0000000000000000 R08: ffffffff835807c2 R09: 0000000000000000 R10: 0000000000000004 R11: ffffed1020b92441 R12: 0000000000000000 R13: 1ffff11006399e08 R14: 0000000000000000 R15: 0000000000000000 FS: 00007fa4c8344700(0000) GS:ffff88811ae00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2f424000 CR3: 000000003e4e2003 CR4: 0000000000770ef0 PKRU: 55555554 Call Trace: tcp_select_window net/ipv4/tcp_output.c:264 [inline] __tcp_transmit_skb+0xc00/0x37a0 net/ipv4/tcp_output.c:1351 __tcp_send_ack.part.0+0x3ec/0x760 net/ipv4/tcp_output.c:3972 __tcp_send_ack net/ipv4/tcp_output.c:3978 [inline] tcp_send_ack+0x7d/0xa0 net/ipv4/tcp_output.c:3978 mptcp_pm_nl_addr_send_ack+0x1ab/0x380 net/mptcp/pm_netlink.c:654 mptcp_pm_remove_addr+0x161/0x200 net/mptcp/pm.c:58 mptcp_nl_remove_id_zero_address+0x197/0x460 net/mptcp/pm_netlink.c:1328 mptcp_nl_cmd_del_addr+0x98b/0xd40 net/mptcp/pm_netlink.c:1359 genl_family_rcv_msg_doit.isra.0+0x225/0x340 net/netlink/genetlink.c:731 genl_family_rcv_msg net/netlink/genetlink.c:775 [inline] genl_rcv_msg+0x341/0x5b0 net/netlink/genetlink.c:792 netlink_rcv_skb+0x148/0x430 net/netlink/af_netlink.c:2504 genl_rcv+0x24/0x40 net/netlink/genetlink.c:803 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x537/0x750 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x846/0xd80 net/netlink/af_netlink.c:1929 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg+0x14e/0x190 net/socket.c:724 ____sys_sendmsg+0x709/0x870 net/socket.c:2403 ___sys_sendmsg+0xff/0x170 net/socket.c:2457 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2486 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae mptcp_pm_nl_addr_send_ack() was attempting to send a TCP ACK on the first subflow in the MPTCP socket's connection list without validating that the subflow was in a suitable connection state. To address this, always validate subflow state when sending extra ACKs on subflows for address advertisement or subflow priority change. Fixes: 84dfe36 ("mptcp: send out dedicated ADD_ADDR packet") Closes: multipath-tcp/mptcp_net-next#229 Co-developed-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Acked-by: Geliang Tang <geliangtang@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
heftig
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Patch series "kasan: test: avoid crashing the kernel with HW_TAGS", v2. KASAN tests do out-of-bounds and use-after-free accesses. Running the tests works fine for the GENERIC mode, as it uses qurantine and redzones. But the HW_TAGS mode uses neither, and running the tests might crash the kernel. Rework the tests to avoid corrupting kernel memory. This patch (of 8): Rework kmalloc_oob_right() to do these bad access checks: 1. An unaligned access one byte past the requested kmalloc size (can only be detected by KASAN_GENERIC). 2. An aligned access into the first out-of-bounds granule that falls within the aligned kmalloc object. 3. Out-of-bounds access past the aligned kmalloc object. Test #3 deliberately uses a read access to avoid corrupting memory. Otherwise, this test might lead to crashes with the HW_TAGS mode, as it neither uses quarantine nor redzones. Link: https://lkml.kernel.org/r/cover.1628779805.git.andreyknvl@gmail.com Link: https://lkml.kernel.org/r/474aa8b7b538c6737a4c6d0090350af2e1776bef.1628779805.git.andreyknvl@gmail.com Signed-off-by: Andrey Konovalov <andreyknvl@gmail.com> Reviewed-by: Marco Elver <elver@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Alexander Potapenko <glider@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Patch series "mm/memory_hotplug: "auto-movable" online policy and memory groups", v3.
I. Goal
The goal of this series is improving in-kernel auto-online support. It
tackles the fundamental problems that:
1) We can create zone imbalances when onlining all memory blindly to
ZONE_MOVABLE, in the worst case crashing the system. We have to know
upfront how much memory we are going to hotplug such that we can
safely enable auto-onlining of all hotplugged memory to ZONE_MOVABLE
via "online_movable". This is far from practical and only applicable in
limited setups -- like inside VMs under the RHV/oVirt hypervisor which
will never hotplug more than 3 times the boot memory (and the
limitation is only in place due to the Linux limitation).
2) We see more setups that implement dynamic VM resizing, hot(un)plugging
memory to resize VM memory. In these setups, we might hotplug a lot of
memory, but it might happen in various small steps in both directions
(e.g., 2 GiB -> 8 GiB -> 4 GiB -> 16 GiB ...). virtio-mem is the
primary driver of this upstream right now, performing such dynamic
resizing NUMA-aware via multiple virtio-mem devices.
Onlining all hotplugged memory to ZONE_NORMAL means we basically have
no hotunplug guarantees. Onlining all to ZONE_MOVABLE means we can
easily run into zone imbalances when growing a VM. We want a mixture,
and we want as much memory as reasonable/configured in ZONE_MOVABLE.
Details regarding zone imbalances can be found at [1].
3) Memory devices consist of 1..X memory block devices, however, the
kernel doesn't really track the relationship. Consequently, also user
space has no idea. We want to make per-device decisions.
As one example, for memory hotunplug it doesn't make sense to use a
mixture of zones within a single DIMM: we want all MOVABLE if
possible, otherwise all !MOVABLE, because any !MOVABLE part will easily
block the whole DIMM from getting hotunplugged.
As another example, virtio-mem operates on individual units that span
1..X memory blocks. Similar to a DIMM, we want a unit to either be all
MOVABLE or !MOVABLE. A "unit" can be thought of like a DIMM, however,
all units of a virtio-mem device logically belong together and are
managed (added/removed) by a single driver. We want as much memory of
a virtio-mem device to be MOVABLE as possible.
4) We want memory onlining to be done right from the kernel while adding
memory, not triggered by user space via udev rules; for example, this
is reqired for fast memory hotplug for drivers that add individual
memory blocks, like virito-mem. We want a way to configure a policy in
the kernel and avoid implementing advanced policies in user space.
The auto-onlining support we have in the kernel is not sufficient. All we
have is a) online everything MOVABLE (online_movable) b) online everything
!MOVABLE (online_kernel) c) keep zones contiguous (online). This series
allows configuring c) to mean instead "online movable if possible
according to the coniguration, driven by a maximum MOVABLE:KERNEL ratio"
-- a new onlining policy.
II. Approach
This series does 3 things:
1) Introduces the "auto-movable" online policy that initially operates on
individual memory blocks only. It uses a maximum MOVABLE:KERNEL ratio
to make a decision whether a memory block will be onlined to
ZONE_MOVABLE or not. However, in the basic form, hotplugged KERNEL
memory does not allow for more MOVABLE memory (details in the
patches). CMA memory is treated like MOVABLE memory.
2) Introduces static (e.g., DIMM) and dynamic (e.g., virtio-mem) memory
groups and uses group information to make decisions in the
"auto-movable" online policy across memory blocks of a single memory
device (modeled as memory group). More details can be found in patch
#3 or in the DIMM example below.
3) Maximizes ZONE_MOVABLE memory within dynamic memory groups, by
allowing ZONE_NORMAL memory within a dynamic memory group to allow for
more ZONE_MOVABLE memory within the same memory group. The target use
case is dynamic VM resizing using virtio-mem. See the virtio-mem
example below.
I remember that the basic idea of using a ratio to implement a policy in
the kernel was once mentioned by Vitaly Kuznetsov, but I might be wrong (I
lost the pointer to that discussion).
For me, the main use case is using it along with virtio-mem (and DIMMs /
ppc64 dlpar where necessary) for dynamic resizing of VMs, increasing the
amount of memory we can hotunplug reliably again if we might eventually
hotplug a lot of memory to a VM.
III. Target Usage
The target usage will be:
1) Linux boots with "mhp_default_online_type=offline"
2) User space (e.g., systemd unit) configures memory onlining (according
to a config file and system properties), for example:
* Setting memory_hotplug.online_policy=auto-movable
* Setting memory_hotplug.auto_movable_ratio=301
* Setting memory_hotplug.auto_movable_numa_aware=true
3) User space enabled auto onlining via "echo online >
/sys/devices/system/memory/auto_online_blocks"
4) User space triggers manual onlining of all already-offline memory
blocks (go over offline memory blocks and set them to "online")
IV. Example
For DIMMs, hotplugging 4 GiB DIMMs to a 4 GiB VM with a configured ratio of
301% results in the following layout:
Memory block 0-15: DMA32 (early)
Memory block 32-47: Normal (early)
Memory block 48-79: Movable (DIMM 0)
Memory block 80-111: Movable (DIMM 1)
Memory block 112-143: Movable (DIMM 2)
Memory block 144-275: Normal (DIMM 3)
Memory block 176-207: Normal (DIMM 4)
... all Normal
(-> hotplugged Normal memory does not allow for more Movable memory)
For virtio-mem, using a simple, single virtio-mem device with a 4 GiB VM
will result in the following layout:
Memory block 0-15: DMA32 (early)
Memory block 32-47: Normal (early)
Memory block 48-143: Movable (virtio-mem, first 12 GiB)
Memory block 144: Normal (virtio-mem, next 128 MiB)
Memory block 145-147: Movable (virtio-mem, next 384 MiB)
Memory block 148: Normal (virtio-mem, next 128 MiB)
Memory block 149-151: Movable (virtio-mem, next 384 MiB)
... Normal/Movable mixture as above
(-> hotplugged Normal memory allows for more Movable memory within
the same device)
Which gives us maximum flexibility when dynamically growing/shrinking a
VM in smaller steps.
V. Doc Update
I'll update the memory-hotplug.rst documentation, once the overhaul [1] is
usptream. Until then, details can be found in patch #2.
VI. Future Work
1) Use memory groups for ppc64 dlpar
2) Being able to specify a portion of (early) kernel memory that will be
excluded from the ratio. Like "128 MiB globally/per node" are excluded.
This might be helpful when starting VMs with extremely small memory
footprint (e.g., 128 MiB) and hotplugging memory later -- not wanting
the first hotplugged units getting onlined to ZONE_MOVABLE. One
alternative would be a trigger to not consider ZONE_DMA memory
in the ratio. We'll have to see if this is really rrequired.
3) Indicate to user space that MOVABLE might be a bad idea -- especially
relevant when memory ballooning without support for balloon compaction
is active.
This patch (of 9):
For implementing a new memory onlining policy, which determines when to
online memory blocks to ZONE_MOVABLE semi-automatically, we need the
number of present early (boot) pages -- present pages excluding hotplugged
pages. Let's track these pages per zone.
Pass a page instead of the zone to adjust_present_page_count(), similar as
adjust_managed_page_count() and derive the zone from the page.
It's worth noting that a memory block to be offlined/onlined is either
completely "early" or "not early". add_memory() and friends can only add
complete memory blocks and we only online/offline complete (individual)
memory blocks.
Link: https://lkml.kernel.org/r/20210806124715.17090-1-david@redhat.com
Link: https://lkml.kernel.org/r/20210806124715.17090-2-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Marek Kedzierski <mkedzier@redhat.com>
Cc: Hui Zhu <teawater@gmail.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Len Brown <lenb@kernel.org>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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When the refcount is decreased to 0, the resource reclamation branch is entered. Before CPU0 reaches the race point (1), CPU1 may obtain the spinlock and traverse the rbtree to find 'root', see nilfs_lookup_root(). Although CPU1 will call refcount_inc() to increase the refcount, it is obviously too late. CPU0 will release 'root' directly, CPU1 then accesses 'root' and triggers UAF. Use refcount_dec_and_lock() to ensure that both the operations of decrease refcount to 0 and link deletion are lock protected eliminates this risk. CPU0 CPU1 nilfs_put_root(): <-------- (1) spin_lock(&nilfs->ns_cptree_lock); rb_erase(&root->rb_node, &nilfs->ns_cptree); spin_unlock(&nilfs->ns_cptree_lock); kfree(root); <-------- use-after-free refcount_t: underflow; use-after-free. WARNING: CPU: 2 PID: 9476 at lib/refcount.c:28 \ refcount_warn_saturate+0x1cf/0x210 lib/refcount.c:28 Modules linked in: CPU: 2 PID: 9476 Comm: syz-executor.0 Not tainted 5.10.45-rc1+ #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), ... RIP: 0010:refcount_warn_saturate+0x1cf/0x210 lib/refcount.c:28 ... ... Call Trace: __refcount_sub_and_test include/linux/refcount.h:283 [inline] __refcount_dec_and_test include/linux/refcount.h:315 [inline] refcount_dec_and_test include/linux/refcount.h:333 [inline] nilfs_put_root+0xc1/0xd0 fs/nilfs2/the_nilfs.c:795 nilfs_segctor_destroy fs/nilfs2/segment.c:2749 [inline] nilfs_detach_log_writer+0x3fa/0x570 fs/nilfs2/segment.c:2812 nilfs_put_super+0x2f/0xf0 fs/nilfs2/super.c:467 generic_shutdown_super+0xcd/0x1f0 fs/super.c:464 kill_block_super+0x4a/0x90 fs/super.c:1446 deactivate_locked_super+0x6a/0xb0 fs/super.c:335 deactivate_super+0x85/0x90 fs/super.c:366 cleanup_mnt+0x277/0x2e0 fs/namespace.c:1118 __cleanup_mnt+0x15/0x20 fs/namespace.c:1125 task_work_run+0x8e/0x110 kernel/task_work.c:151 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop kernel/entry/common.c:164 [inline] exit_to_user_mode_prepare+0x13c/0x170 kernel/entry/common.c:191 syscall_exit_to_user_mode+0x16/0x30 kernel/entry/common.c:266 do_syscall_64+0x45/0x80 arch/x86/entry/common.c:56 entry_SYSCALL_64_after_hwframe+0x44/0xa9 There is no reproduction program, and the above is only theoretical analysis. Link: https://lkml.kernel.org/r/1629859428-5906-1-git-send-email-konishi.ryusuke@gmail.com Fixes: ba65ae4 ("nilfs2: add checkpoint tree to nilfs object") Link: https://lkml.kernel.org/r/20210723012317.4146-1-thunder.leizhen@huawei.com Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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We update the ctime/mtime of a block device when we remove it so that blkid knows the device changed. However we do this by re-opening the block device and calling filp_update_time. This is more correct because it'll call the inode->i_op->update_time if it exists, but the block dev inodes do not do this. Instead call generic_update_time() on the bd_inode in order to avoid the blkdev_open path and get rid of the following lockdep splat: ====================================================== WARNING: possible circular locking dependency detected 5.14.0-rc2+ torvalds#406 Not tainted ------------------------------------------------------ losetup/11596 is trying to acquire lock: ffff939640d2f538 ((wq_completion)loop0){+.+.}-{0:0}, at: flush_workqueue+0x67/0x5e0 but task is already holding lock: ffff939655510c68 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x660 [loop] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&lo->lo_mutex){+.+.}-{3:3}: __mutex_lock+0x7d/0x750 lo_open+0x28/0x60 [loop] blkdev_get_whole+0x25/0xf0 blkdev_get_by_dev.part.0+0x168/0x3c0 blkdev_open+0xd2/0xe0 do_dentry_open+0x161/0x390 path_openat+0x3cc/0xa20 do_filp_open+0x96/0x120 do_sys_openat2+0x7b/0x130 __x64_sys_openat+0x46/0x70 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #3 (&disk->open_mutex){+.+.}-{3:3}: __mutex_lock+0x7d/0x750 blkdev_get_by_dev.part.0+0x56/0x3c0 blkdev_open+0xd2/0xe0 do_dentry_open+0x161/0x390 path_openat+0x3cc/0xa20 do_filp_open+0x96/0x120 file_open_name+0xc7/0x170 filp_open+0x2c/0x50 btrfs_scratch_superblocks.part.0+0x10f/0x170 btrfs_rm_device.cold+0xe8/0xed btrfs_ioctl+0x2a31/0x2e70 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #2 (sb_writers#12){.+.+}-{0:0}: lo_write_bvec+0xc2/0x240 [loop] loop_process_work+0x238/0xd00 [loop] process_one_work+0x26b/0x560 worker_thread+0x55/0x3c0 kthread+0x140/0x160 ret_from_fork+0x1f/0x30 -> #1 ((work_completion)(&lo->rootcg_work)){+.+.}-{0:0}: process_one_work+0x245/0x560 worker_thread+0x55/0x3c0 kthread+0x140/0x160 ret_from_fork+0x1f/0x30 -> #0 ((wq_completion)loop0){+.+.}-{0:0}: __lock_acquire+0x10ea/0x1d90 lock_acquire+0xb5/0x2b0 flush_workqueue+0x91/0x5e0 drain_workqueue+0xa0/0x110 destroy_workqueue+0x36/0x250 __loop_clr_fd+0x9a/0x660 [loop] block_ioctl+0x3f/0x50 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae other info that might help us debug this: Chain exists of: (wq_completion)loop0 --> &disk->open_mutex --> &lo->lo_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&lo->lo_mutex); lock(&disk->open_mutex); lock(&lo->lo_mutex); lock((wq_completion)loop0); *** DEADLOCK *** 1 lock held by losetup/11596: #0: ffff939655510c68 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x660 [loop] stack backtrace: CPU: 1 PID: 11596 Comm: losetup Not tainted 5.14.0-rc2+ torvalds#406 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014 Call Trace: dump_stack_lvl+0x57/0x72 check_noncircular+0xcf/0xf0 ? stack_trace_save+0x3b/0x50 __lock_acquire+0x10ea/0x1d90 lock_acquire+0xb5/0x2b0 ? flush_workqueue+0x67/0x5e0 ? lockdep_init_map_type+0x47/0x220 flush_workqueue+0x91/0x5e0 ? flush_workqueue+0x67/0x5e0 ? verify_cpu+0xf0/0x100 drain_workqueue+0xa0/0x110 destroy_workqueue+0x36/0x250 __loop_clr_fd+0x9a/0x660 [loop] ? blkdev_ioctl+0x8d/0x2a0 block_ioctl+0x3f/0x50 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Sep 12, 2021
When removing the device we call blkdev_put() on the device once we've removed it, and because we have an EXCL open we need to take the ->open_mutex on the block device to clean it up. Unfortunately during device remove we are holding the sb writers lock, which results in the following lockdep splat: ====================================================== WARNING: possible circular locking dependency detected 5.14.0-rc2+ torvalds#407 Not tainted ------------------------------------------------------ losetup/11595 is trying to acquire lock: ffff973ac35dd138 ((wq_completion)loop0){+.+.}-{0:0}, at: flush_workqueue+0x67/0x5e0 but task is already holding lock: ffff973ac9812c68 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x660 [loop] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&lo->lo_mutex){+.+.}-{3:3}: __mutex_lock+0x7d/0x750 lo_open+0x28/0x60 [loop] blkdev_get_whole+0x25/0xf0 blkdev_get_by_dev.part.0+0x168/0x3c0 blkdev_open+0xd2/0xe0 do_dentry_open+0x161/0x390 path_openat+0x3cc/0xa20 do_filp_open+0x96/0x120 do_sys_openat2+0x7b/0x130 __x64_sys_openat+0x46/0x70 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #3 (&disk->open_mutex){+.+.}-{3:3}: __mutex_lock+0x7d/0x750 blkdev_put+0x3a/0x220 btrfs_rm_device.cold+0x62/0xe5 btrfs_ioctl+0x2a31/0x2e70 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #2 (sb_writers#12){.+.+}-{0:0}: lo_write_bvec+0xc2/0x240 [loop] loop_process_work+0x238/0xd00 [loop] process_one_work+0x26b/0x560 worker_thread+0x55/0x3c0 kthread+0x140/0x160 ret_from_fork+0x1f/0x30 -> #1 ((work_completion)(&lo->rootcg_work)){+.+.}-{0:0}: process_one_work+0x245/0x560 worker_thread+0x55/0x3c0 kthread+0x140/0x160 ret_from_fork+0x1f/0x30 -> #0 ((wq_completion)loop0){+.+.}-{0:0}: __lock_acquire+0x10ea/0x1d90 lock_acquire+0xb5/0x2b0 flush_workqueue+0x91/0x5e0 drain_workqueue+0xa0/0x110 destroy_workqueue+0x36/0x250 __loop_clr_fd+0x9a/0x660 [loop] block_ioctl+0x3f/0x50 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae other info that might help us debug this: Chain exists of: (wq_completion)loop0 --> &disk->open_mutex --> &lo->lo_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&lo->lo_mutex); lock(&disk->open_mutex); lock(&lo->lo_mutex); lock((wq_completion)loop0); *** DEADLOCK *** 1 lock held by losetup/11595: #0: ffff973ac9812c68 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x660 [loop] stack backtrace: CPU: 0 PID: 11595 Comm: losetup Not tainted 5.14.0-rc2+ torvalds#407 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014 Call Trace: dump_stack_lvl+0x57/0x72 check_noncircular+0xcf/0xf0 ? stack_trace_save+0x3b/0x50 __lock_acquire+0x10ea/0x1d90 lock_acquire+0xb5/0x2b0 ? flush_workqueue+0x67/0x5e0 ? lockdep_init_map_type+0x47/0x220 flush_workqueue+0x91/0x5e0 ? flush_workqueue+0x67/0x5e0 ? verify_cpu+0xf0/0x100 drain_workqueue+0xa0/0x110 destroy_workqueue+0x36/0x250 __loop_clr_fd+0x9a/0x660 [loop] ? blkdev_ioctl+0x8d/0x2a0 block_ioctl+0x3f/0x50 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fc21255d4cb So instead save the bdev and do the put once we've dropped the sb writers lock in order to avoid the lockdep recursion. Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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If CONFIG_BLK_DEV_LOOP && CONFIG_MTD (at least; there might be other combinations), lockdep complains circular locking dependency at __loop_clr_fd(), for major_names_lock serves as a locking dependency aggregating hub across multiple block modules. ====================================================== WARNING: possible circular locking dependency detected 5.14.0+ torvalds#757 Tainted: G E ------------------------------------------------------ systemd-udevd/7568 is trying to acquire lock: ffff88800f334d48 ((wq_completion)loop0){+.+.}-{0:0}, at: flush_workqueue+0x70/0x560 but task is already holding lock: ffff888014a7d4a0 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x4d/0x400 [loop] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #6 (&lo->lo_mutex){+.+.}-{3:3}: lock_acquire+0xbe/0x1f0 __mutex_lock_common+0xb6/0xe10 mutex_lock_killable_nested+0x17/0x20 lo_open+0x23/0x50 [loop] blkdev_get_by_dev+0x199/0x540 blkdev_open+0x58/0x90 do_dentry_open+0x144/0x3a0 path_openat+0xa57/0xda0 do_filp_open+0x9f/0x140 do_sys_openat2+0x71/0x150 __x64_sys_openat+0x78/0xa0 do_syscall_64+0x3d/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #5 (&disk->open_mutex){+.+.}-{3:3}: lock_acquire+0xbe/0x1f0 __mutex_lock_common+0xb6/0xe10 mutex_lock_nested+0x17/0x20 bd_register_pending_holders+0x20/0x100 device_add_disk+0x1ae/0x390 loop_add+0x29c/0x2d0 [loop] blk_request_module+0x5a/0xb0 blkdev_get_no_open+0x27/0xa0 blkdev_get_by_dev+0x5f/0x540 blkdev_open+0x58/0x90 do_dentry_open+0x144/0x3a0 path_openat+0xa57/0xda0 do_filp_open+0x9f/0x140 do_sys_openat2+0x71/0x150 __x64_sys_openat+0x78/0xa0 do_syscall_64+0x3d/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #4 (major_names_lock){+.+.}-{3:3}: lock_acquire+0xbe/0x1f0 __mutex_lock_common+0xb6/0xe10 mutex_lock_nested+0x17/0x20 blkdev_show+0x19/0x80 devinfo_show+0x52/0x60 seq_read_iter+0x2d5/0x3e0 proc_reg_read_iter+0x41/0x80 vfs_read+0x2ac/0x330 ksys_read+0x6b/0xd0 do_syscall_64+0x3d/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #3 (&p->lock){+.+.}-{3:3}: lock_acquire+0xbe/0x1f0 __mutex_lock_common+0xb6/0xe10 mutex_lock_nested+0x17/0x20 seq_read_iter+0x37/0x3e0 generic_file_splice_read+0xf3/0x170 splice_direct_to_actor+0x14e/0x350 do_splice_direct+0x84/0xd0 do_sendfile+0x263/0x430 __se_sys_sendfile64+0x96/0xc0 do_syscall_64+0x3d/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #2 (sb_writers#3){.+.+}-{0:0}: lock_acquire+0xbe/0x1f0 lo_write_bvec+0x96/0x280 [loop] loop_process_work+0xa68/0xc10 [loop] process_one_work+0x293/0x480 worker_thread+0x23d/0x4b0 kthread+0x163/0x180 ret_from_fork+0x1f/0x30 -> #1 ((work_completion)(&lo->rootcg_work)){+.+.}-{0:0}: lock_acquire+0xbe/0x1f0 process_one_work+0x280/0x480 worker_thread+0x23d/0x4b0 kthread+0x163/0x180 ret_from_fork+0x1f/0x30 -> #0 ((wq_completion)loop0){+.+.}-{0:0}: validate_chain+0x1f0d/0x33e0 __lock_acquire+0x92d/0x1030 lock_acquire+0xbe/0x1f0 flush_workqueue+0x8c/0x560 drain_workqueue+0x80/0x140 destroy_workqueue+0x47/0x4f0 __loop_clr_fd+0xb4/0x400 [loop] blkdev_put+0x14a/0x1d0 blkdev_close+0x1c/0x20 __fput+0xfd/0x220 task_work_run+0x69/0xc0 exit_to_user_mode_prepare+0x1ce/0x1f0 syscall_exit_to_user_mode+0x26/0x60 do_syscall_64+0x4c/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae other info that might help us debug this: Chain exists of: (wq_completion)loop0 --> &disk->open_mutex --> &lo->lo_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&lo->lo_mutex); lock(&disk->open_mutex); lock(&lo->lo_mutex); lock((wq_completion)loop0); *** DEADLOCK *** 2 locks held by systemd-udevd/7568: #0: ffff888012554128 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0x4c/0x1d0 #1: ffff888014a7d4a0 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x4d/0x400 [loop] stack backtrace: CPU: 0 PID: 7568 Comm: systemd-udevd Tainted: G E 5.14.0+ torvalds#757 Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 02/27/2020 Call Trace: dump_stack_lvl+0x79/0xbf print_circular_bug+0x5d6/0x5e0 ? stack_trace_save+0x42/0x60 ? save_trace+0x3d/0x2d0 check_noncircular+0x10b/0x120 validate_chain+0x1f0d/0x33e0 ? __lock_acquire+0x953/0x1030 ? __lock_acquire+0x953/0x1030 __lock_acquire+0x92d/0x1030 ? flush_workqueue+0x70/0x560 lock_acquire+0xbe/0x1f0 ? flush_workqueue+0x70/0x560 flush_workqueue+0x8c/0x560 ? flush_workqueue+0x70/0x560 ? sched_clock_cpu+0xe/0x1a0 ? drain_workqueue+0x41/0x140 drain_workqueue+0x80/0x140 destroy_workqueue+0x47/0x4f0 ? blk_mq_freeze_queue_wait+0xac/0xd0 __loop_clr_fd+0xb4/0x400 [loop] ? __mutex_unlock_slowpath+0x35/0x230 blkdev_put+0x14a/0x1d0 blkdev_close+0x1c/0x20 __fput+0xfd/0x220 task_work_run+0x69/0xc0 exit_to_user_mode_prepare+0x1ce/0x1f0 syscall_exit_to_user_mode+0x26/0x60 do_syscall_64+0x4c/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f0fd4c661f7 Code: 00 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 41 c3 48 83 ec 18 89 7c 24 0c e8 13 fc ff ff RSP: 002b:00007ffd1c9e9fd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 00007f0fd46be6c8 RCX: 00007f0fd4c661f7 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000006 RBP: 0000000000000006 R08: 000055fff1eaf400 R09: 0000000000000000 R10: 00007f0fd46be6c8 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000002f08 R15: 00007ffd1c9ea050 Commit 1c500ad ("loop: reduce the loop_ctl_mutex scope") is for breaking "loop_ctl_mutex => &lo->lo_mutex" dependency chain. But enabling a different block module results in forming circular locking dependency due to shared major_names_lock mutex. The simplest fix is to call probe function without holding major_names_lock [1], but Christoph Hellwig does not like such idea. Therefore, instead of holding major_names_lock in blkdev_show(), introduce a different lock for blkdev_show() in order to break "sb_writers#$N => &p->lock => major_names_lock" dependency chain. Link: https://lkml.kernel.org/r/b2af8a5b-3c1b-204e-7f56-bea0b15848d6@i-love.sakura.ne.jp [1] Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Link: https://lore.kernel.org/r/18a02da2-0bf3-550e-b071-2b4ab13c49f0@i-love.sakura.ne.jp Signed-off-by: Jens Axboe <axboe@kernel.dk>
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As previously noted in commit 66e4f4a ("rtc: cmos: Use spin_lock_irqsave() in cmos_interrupt()"): <4>[ 254.192378] WARNING: inconsistent lock state <4>[ 254.192384] 5.12.0-rc1-CI-CI_DRM_9834+ #1 Not tainted <4>[ 254.192396] -------------------------------- <4>[ 254.192400] inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage. <4>[ 254.192409] rtcwake/5309 [HC0[0]:SC0[0]:HE1:SE1] takes: <4>[ 254.192429] ffffffff8263c5f8 (rtc_lock){?...}-{2:2}, at: cmos_interrupt+0x18/0x100 <4>[ 254.192481] {IN-HARDIRQ-W} state was registered at: <4>[ 254.192488] lock_acquire+0xd1/0x3d0 <4>[ 254.192504] _raw_spin_lock+0x2a/0x40 <4>[ 254.192519] cmos_interrupt+0x18/0x100 <4>[ 254.192536] rtc_handler+0x1f/0xc0 <4>[ 254.192553] acpi_ev_fixed_event_detect+0x109/0x13c <4>[ 254.192574] acpi_ev_sci_xrupt_handler+0xb/0x28 <4>[ 254.192596] acpi_irq+0x13/0x30 <4>[ 254.192620] __handle_irq_event_percpu+0x43/0x2c0 <4>[ 254.192641] handle_irq_event_percpu+0x2b/0x70 <4>[ 254.192661] handle_irq_event+0x2f/0x50 <4>[ 254.192680] handle_fasteoi_irq+0x9e/0x150 <4>[ 254.192693] __common_interrupt+0x76/0x140 <4>[ 254.192715] common_interrupt+0x96/0xc0 <4>[ 254.192732] asm_common_interrupt+0x1e/0x40 <4>[ 254.192750] _raw_spin_unlock_irqrestore+0x38/0x60 <4>[ 254.192767] resume_irqs+0xba/0xf0 <4>[ 254.192786] dpm_resume_noirq+0x245/0x3d0 <4>[ 254.192811] suspend_devices_and_enter+0x230/0xaa0 <4>[ 254.192835] pm_suspend.cold.8+0x301/0x34a <4>[ 254.192859] state_store+0x7b/0xe0 <4>[ 254.192879] kernfs_fop_write_iter+0x11d/0x1c0 <4>[ 254.192899] new_sync_write+0x11d/0x1b0 <4>[ 254.192916] vfs_write+0x265/0x390 <4>[ 254.192933] ksys_write+0x5a/0xd0 <4>[ 254.192949] do_syscall_64+0x33/0x80 <4>[ 254.192965] entry_SYSCALL_64_after_hwframe+0x44/0xae <4>[ 254.192986] irq event stamp: 43775 <4>[ 254.192994] hardirqs last enabled at (43775): [<ffffffff81c00c42>] asm_sysvec_apic_timer_interrupt+0x12/0x20 <4>[ 254.193023] hardirqs last disabled at (43774): [<ffffffff81aa691a>] sysvec_apic_timer_interrupt+0xa/0xb0 <4>[ 254.193049] softirqs last enabled at (42548): [<ffffffff81e00342>] __do_softirq+0x342/0x48e <4>[ 254.193074] softirqs last disabled at (42543): [<ffffffff810b45fd>] irq_exit_rcu+0xad/0xd0 <4>[ 254.193101] other info that might help us debug this: <4>[ 254.193107] Possible unsafe locking scenario: <4>[ 254.193112] CPU0 <4>[ 254.193117] ---- <4>[ 254.193121] lock(rtc_lock); <4>[ 254.193137] <Interrupt> <4>[ 254.193142] lock(rtc_lock); <4>[ 254.193156] *** DEADLOCK *** <4>[ 254.193161] 6 locks held by rtcwake/5309: <4>[ 254.193174] #0: ffff888104861430 (sb_writers#5){.+.+}-{0:0}, at: ksys_write+0x5a/0xd0 <4>[ 254.193232] #1: ffff88810f823288 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0xe7/0x1c0 <4>[ 254.193282] #2: ffff888100cef3c0 (kn->active#285 <7>[ 254.192706] i915 0000:00:02.0: [drm:intel_modeset_setup_hw_state [i915]] [CRTC:51:pipe A] hw state readout: disabled <4>[ 254.193307] ){.+.+}-{0:0}, at: kernfs_fop_write_iter+0xf0/0x1c0 <4>[ 254.193333] #3: ffffffff82649fa8 (system_transition_mutex){+.+.}-{3:3}, at: pm_suspend.cold.8+0xce/0x34a <4>[ 254.193387] #4: ffffffff827a2108 (acpi_scan_lock){+.+.}-{3:3}, at: acpi_suspend_begin+0x47/0x70 <4>[ 254.193433] #5: ffff8881019ea178 (&dev->mutex){....}-{3:3}, at: device_resume+0x68/0x1e0 <4>[ 254.193485] stack backtrace: <4>[ 254.193492] CPU: 1 PID: 5309 Comm: rtcwake Not tainted 5.12.0-rc1-CI-CI_DRM_9834+ #1 <4>[ 254.193514] Hardware name: Google Soraka/Soraka, BIOS MrChromebox-4.10 08/25/2019 <4>[ 254.193524] Call Trace: <4>[ 254.193536] dump_stack+0x7f/0xad <4>[ 254.193567] mark_lock.part.47+0x8ca/0xce0 <4>[ 254.193604] __lock_acquire+0x39b/0x2590 <4>[ 254.193626] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 <4>[ 254.193660] lock_acquire+0xd1/0x3d0 <4>[ 254.193677] ? cmos_interrupt+0x18/0x100 <4>[ 254.193716] _raw_spin_lock+0x2a/0x40 <4>[ 254.193735] ? cmos_interrupt+0x18/0x100 <4>[ 254.193758] cmos_interrupt+0x18/0x100 <4>[ 254.193785] cmos_resume+0x2ac/0x2d0 <4>[ 254.193813] ? acpi_pm_set_device_wakeup+0x1f/0x110 <4>[ 254.193842] ? pnp_bus_suspend+0x10/0x10 <4>[ 254.193864] pnp_bus_resume+0x5e/0x90 <4>[ 254.193885] dpm_run_callback+0x5f/0x240 <4>[ 254.193914] device_resume+0xb2/0x1e0 <4>[ 254.193942] ? pm_dev_err+0x25/0x25 <4>[ 254.193974] dpm_resume+0xea/0x3f0 <4>[ 254.194005] dpm_resume_end+0x8/0x10 <4>[ 254.194030] suspend_devices_and_enter+0x29b/0xaa0 <4>[ 254.194066] pm_suspend.cold.8+0x301/0x34a <4>[ 254.194094] state_store+0x7b/0xe0 <4>[ 254.194124] kernfs_fop_write_iter+0x11d/0x1c0 <4>[ 254.194151] new_sync_write+0x11d/0x1b0 <4>[ 254.194183] vfs_write+0x265/0x390 <4>[ 254.194207] ksys_write+0x5a/0xd0 <4>[ 254.194232] do_syscall_64+0x33/0x80 <4>[ 254.194251] entry_SYSCALL_64_after_hwframe+0x44/0xae <4>[ 254.194274] RIP: 0033:0x7f07d79691e7 <4>[ 254.194293] Code: 64 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24 <4>[ 254.194312] RSP: 002b:00007ffd9cc2c768 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 <4>[ 254.194337] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f07d79691e7 <4>[ 254.194352] RDX: 0000000000000004 RSI: 0000556ebfc63590 RDI: 000000000000000b <4>[ 254.194366] RBP: 0000556ebfc63590 R08: 0000000000000000 R09: 0000000000000004 <4>[ 254.194379] R10: 0000556ebf0ec2a6 R11: 0000000000000246 R12: 0000000000000004 which breaks S3-resume on fi-kbl-soraka presumably as that's slow enough to trigger the alarm during the suspend. Fixes: 6950d04 ("rtc: cmos: Replace spin_lock_irqsave with spin_lock in hard IRQ") References: 66e4f4a ("rtc: cmos: Use spin_lock_irqsave() in cmos_interrupt()"): Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Xiaofei Tan <tanxiaofei@huawei.com> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Link: https://lore.kernel.org/r/20210305122140.28774-1-chris@chris-wilson.co.uk
heftig
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Sep 22, 2021
It's later supposed to be either a correct address or NULL. Without the initialization, it may contain an undefined value which results in the following segmentation fault: # perf top --sort comm -g --ignore-callees=do_idle terminates with: #0 0x00007ffff56b7685 in __strlen_avx2 () from /lib64/libc.so.6 #1 0x00007ffff55e3802 in strdup () from /lib64/libc.so.6 #2 0x00005555558cb139 in hist_entry__init (callchain_size=<optimized out>, sample_self=true, template=0x7fffde7fb110, he=0x7fffd801c250) at util/hist.c:489 #3 hist_entry__new (template=template@entry=0x7fffde7fb110, sample_self=sample_self@entry=true) at util/hist.c:564 #4 0x00005555558cb4ba in hists__findnew_entry (hists=hists@entry=0x5555561d9e38, entry=entry@entry=0x7fffde7fb110, al=al@entry=0x7fffde7fb420, sample_self=sample_self@entry=true) at util/hist.c:657 #5 0x00005555558cba1b in __hists__add_entry (hists=hists@entry=0x5555561d9e38, al=0x7fffde7fb420, sym_parent=<optimized out>, bi=bi@entry=0x0, mi=mi@entry=0x0, sample=sample@entry=0x7fffde7fb4b0, sample_self=true, ops=0x0, block_info=0x0) at util/hist.c:288 #6 0x00005555558cbb70 in hists__add_entry (sample_self=true, sample=0x7fffde7fb4b0, mi=0x0, bi=0x0, sym_parent=<optimized out>, al=<optimized out>, hists=0x5555561d9e38) at util/hist.c:1056 #7 iter_add_single_cumulative_entry (iter=0x7fffde7fb460, al=<optimized out>) at util/hist.c:1056 #8 0x00005555558cc8a4 in hist_entry_iter__add (iter=iter@entry=0x7fffde7fb460, al=al@entry=0x7fffde7fb420, max_stack_depth=<optimized out>, arg=arg@entry=0x7fffffff7db0) at util/hist.c:1231 #9 0x00005555557cdc9a in perf_event__process_sample (machine=<optimized out>, sample=0x7fffde7fb4b0, evsel=<optimized out>, event=<optimized out>, tool=0x7fffffff7db0) at builtin-top.c:842 torvalds#10 deliver_event (qe=<optimized out>, qevent=<optimized out>) at builtin-top.c:1202 torvalds#11 0x00005555558a9318 in do_flush (show_progress=false, oe=0x7fffffff80e0) at util/ordered-events.c:244 torvalds#12 __ordered_events__flush (oe=oe@entry=0x7fffffff80e0, how=how@entry=OE_FLUSH__TOP, timestamp=timestamp@entry=0) at util/ordered-events.c:323 torvalds#13 0x00005555558a9789 in __ordered_events__flush (timestamp=<optimized out>, how=<optimized out>, oe=<optimized out>) at util/ordered-events.c:339 torvalds#14 ordered_events__flush (how=OE_FLUSH__TOP, oe=0x7fffffff80e0) at util/ordered-events.c:341 torvalds#15 ordered_events__flush (oe=oe@entry=0x7fffffff80e0, how=how@entry=OE_FLUSH__TOP) at util/ordered-events.c:339 torvalds#16 0x00005555557cd631 in process_thread (arg=0x7fffffff7db0) at builtin-top.c:1114 torvalds#17 0x00007ffff7bb817a in start_thread () from /lib64/libpthread.so.0 torvalds#18 0x00007ffff5656dc3 in clone () from /lib64/libc.so.6 If you look at the frame #2, the code is: 488 if (he->srcline) { 489 he->srcline = strdup(he->srcline); 490 if (he->srcline == NULL) 491 goto err_rawdata; 492 } If he->srcline is not NULL (it is not NULL if it is uninitialized rubbish), it gets strdupped and strdupping a rubbish random string causes the problem. Also, if you look at the commit 1fb7d06, it adds the srcline property into the struct, but not initializing it everywhere needed. Committer notes: Now I see, when using --ignore-callees=do_idle we end up here at line 2189 in add_callchain_ip(): 2181 if (al.sym != NULL) { 2182 if (perf_hpp_list.parent && !*parent && 2183 symbol__match_regex(al.sym, &parent_regex)) 2184 *parent = al.sym; 2185 else if (have_ignore_callees && root_al && 2186 symbol__match_regex(al.sym, &ignore_callees_regex)) { 2187 /* Treat this symbol as the root, 2188 forgetting its callees. */ 2189 *root_al = al; 2190 callchain_cursor_reset(cursor); 2191 } 2192 } And the al that doesn't have the ->srcline field initialized will be copied to the root_al, so then, back to: 1211 int hist_entry_iter__add(struct hist_entry_iter *iter, struct addr_location *al, 1212 int max_stack_depth, void *arg) 1213 { 1214 int err, err2; 1215 struct map *alm = NULL; 1216 1217 if (al) 1218 alm = map__get(al->map); 1219 1220 err = sample__resolve_callchain(iter->sample, &callchain_cursor, &iter->parent, 1221 iter->evsel, al, max_stack_depth); 1222 if (err) { 1223 map__put(alm); 1224 return err; 1225 } 1226 1227 err = iter->ops->prepare_entry(iter, al); 1228 if (err) 1229 goto out; 1230 1231 err = iter->ops->add_single_entry(iter, al); 1232 if (err) 1233 goto out; 1234 That al at line 1221 is what hist_entry_iter__add() (called from sample__resolve_callchain()) saw as 'root_al', and then: iter->ops->add_single_entry(iter, al); will go on with al->srcline with a bogus value, I'll add the above sequence to the cset and apply, thanks! Signed-off-by: Michael Petlan <mpetlan@redhat.com> CC: Milian Wolff <milian.wolff@kdab.com> Cc: Jiri Olsa <jolsa@redhat.com> Fixes: 1fb7d06 ("perf report Use srcline from callchain for hist entries") Link: https //lore.kernel.org/r/20210719145332.29747-1-mpetlan@redhat.com Reported-by: Juri Lelli <jlelli@redhat.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
heftig
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Sep 22, 2021
FD uses xyarray__entry that may return NULL if an index is out of
bounds. If NULL is returned then a segv happens as FD unconditionally
dereferences the pointer. This was happening in a case of with perf
iostat as shown below. The fix is to make FD an "int*" rather than an
int and handle the NULL case as either invalid input or a closed fd.
$ sudo gdb --args perf stat --iostat list
...
Breakpoint 1, perf_evsel__alloc_fd (evsel=0x5555560951a0, ncpus=1, nthreads=1) at evsel.c:50
50 {
(gdb) bt
#0 perf_evsel__alloc_fd (evsel=0x5555560951a0, ncpus=1, nthreads=1) at evsel.c:50
#1 0x000055555585c188 in evsel__open_cpu (evsel=0x5555560951a0, cpus=0x555556093410,
threads=0x555556086fb0, start_cpu=0, end_cpu=1) at util/evsel.c:1792
#2 0x000055555585cfb2 in evsel__open (evsel=0x5555560951a0, cpus=0x0, threads=0x555556086fb0)
at util/evsel.c:2045
#3 0x000055555585d0db in evsel__open_per_thread (evsel=0x5555560951a0, threads=0x555556086fb0)
at util/evsel.c:2065
#4 0x00005555558ece64 in create_perf_stat_counter (evsel=0x5555560951a0,
config=0x555555c34700 <stat_config>, target=0x555555c2f1c0 <target>, cpu=0) at util/stat.c:590
#5 0x000055555578e927 in __run_perf_stat (argc=1, argv=0x7fffffffe4a0, run_idx=0)
at builtin-stat.c:833
#6 0x000055555578f3c6 in run_perf_stat (argc=1, argv=0x7fffffffe4a0, run_idx=0)
at builtin-stat.c:1048
#7 0x0000555555792ee5 in cmd_stat (argc=1, argv=0x7fffffffe4a0) at builtin-stat.c:2534
#8 0x0000555555835ed3 in run_builtin (p=0x555555c3f540 <commands+288>, argc=3,
argv=0x7fffffffe4a0) at perf.c:313
#9 0x0000555555836154 in handle_internal_command (argc=3, argv=0x7fffffffe4a0) at perf.c:365
torvalds#10 0x000055555583629f in run_argv (argcp=0x7fffffffe2ec, argv=0x7fffffffe2e0) at perf.c:409
torvalds#11 0x0000555555836692 in main (argc=3, argv=0x7fffffffe4a0) at perf.c:539
...
(gdb) c
Continuing.
Error:
The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (uncore_iio_0/event=0x83,umask=0x04,ch_mask=0xF,fc_mask=0x07/).
/bin/dmesg | grep -i perf may provide additional information.
Program received signal SIGSEGV, Segmentation fault.
0x00005555559b03ea in perf_evsel__close_fd_cpu (evsel=0x5555560951a0, cpu=1) at evsel.c:166
166 if (FD(evsel, cpu, thread) >= 0)
v3. fixes a bug in perf_evsel__run_ioctl where the sense of a branch was
backward.
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20210918054440.2350466-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
dmdemoura
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Oct 6, 2021
[ Upstream commit 21e3980 ] vctrl_enable() and vctrl_disable() call regulator_enable() and regulator_disable(), respectively. However, vctrl_* are regulator ops and should not be calling the locked regulator APIs. Doing so results in a lockdep warning. Instead of exporting more internal regulator ops, model the ctrl supply as an actual supply to vctrl-regulator. At probe time this driver still needs to use the consumer API to fetch its constraints, but otherwise lets the regulator core handle the upstream supply for it. The enable/disable/is_enabled ops are not removed, but now only track state internally. This preserves the original behavior with the ops being available, but one could argue that the original behavior was already incorrect: the internal state would not match the upstream supply if that supply had another consumer that enabled the supply, while vctrl-regulator was not enabled. The lockdep warning is as follows: WARNING: possible circular locking dependency detected 5.14.0-rc6 archlinux#2 Not tainted ------------------------------------------------------ swapper/0/1 is trying to acquire lock: ffffffc011306d00 (regulator_list_mutex){+.+.}-{3:3}, at: regulator_lock_dependent (arch/arm64/include/asm/current.h:19 include/linux/ww_mutex.h:111 drivers/regulator/core.c:329) but task is already holding lock: ffffff8004a77160 (regulator_ww_class_mutex){+.+.}-{3:3}, at: regulator_lock_recursive (drivers/regulator/core.c:156 drivers/regulator/core.c:263) which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> archlinux#2 (regulator_ww_class_mutex){+.+.}-{3:3}: __mutex_lock_common (include/asm-generic/atomic-instrumented.h:606 include/asm-generic/atomic-long.h:29 kernel/locking/mutex.c:103 kernel/locking/mutex.c:144 kernel/locking/mutex.c:963) ww_mutex_lock (kernel/locking/mutex.c:1199) regulator_lock_recursive (drivers/regulator/core.c:156 drivers/regulator/core.c:263) regulator_lock_dependent (drivers/regulator/core.c:343) regulator_enable (drivers/regulator/core.c:2808) set_machine_constraints (drivers/regulator/core.c:1536) regulator_register (drivers/regulator/core.c:5486) devm_regulator_register (drivers/regulator/devres.c:196) reg_fixed_voltage_probe (drivers/regulator/fixed.c:289) platform_probe (drivers/base/platform.c:1427) [...] -> archlinux#1 (regulator_ww_class_acquire){+.+.}-{0:0}: regulator_lock_dependent (include/linux/ww_mutex.h:129 drivers/regulator/core.c:329) regulator_enable (drivers/regulator/core.c:2808) set_machine_constraints (drivers/regulator/core.c:1536) regulator_register (drivers/regulator/core.c:5486) devm_regulator_register (drivers/regulator/devres.c:196) reg_fixed_voltage_probe (drivers/regulator/fixed.c:289) [...] -> #0 (regulator_list_mutex){+.+.}-{3:3}: __lock_acquire (kernel/locking/lockdep.c:3052 (discriminator 4) kernel/locking/lockdep.c:3174 (discriminator 4) kernel/locking/lockdep.c:3789 (discriminator 4) kernel/locking/lockdep.c:5015 (discriminator 4)) lock_acquire (arch/arm64/include/asm/percpu.h:39 kernel/locking/lockdep.c:438 kernel/locking/lockdep.c:5627) __mutex_lock_common (include/asm-generic/atomic-instrumented.h:606 include/asm-generic/atomic-long.h:29 kernel/locking/mutex.c:103 kernel/locking/mutex.c:144 kernel/locking/mutex.c:963) mutex_lock_nested (kernel/locking/mutex.c:1125) regulator_lock_dependent (arch/arm64/include/asm/current.h:19 include/linux/ww_mutex.h:111 drivers/regulator/core.c:329) regulator_enable (drivers/regulator/core.c:2808) vctrl_enable (drivers/regulator/vctrl-regulator.c:400) _regulator_do_enable (drivers/regulator/core.c:2617) _regulator_enable (drivers/regulator/core.c:2764) regulator_enable (drivers/regulator/core.c:308 drivers/regulator/core.c:2809) _set_opp (drivers/opp/core.c:819 drivers/opp/core.c:1072) dev_pm_opp_set_rate (drivers/opp/core.c:1164) set_target (drivers/cpufreq/cpufreq-dt.c:62) __cpufreq_driver_target (drivers/cpufreq/cpufreq.c:2216 drivers/cpufreq/cpufreq.c:2271) cpufreq_online (drivers/cpufreq/cpufreq.c:1488 (discriminator 2)) cpufreq_add_dev (drivers/cpufreq/cpufreq.c:1563) subsys_interface_register (drivers/base/bus.c:?) cpufreq_register_driver (drivers/cpufreq/cpufreq.c:2819) dt_cpufreq_probe (drivers/cpufreq/cpufreq-dt.c:344) [...] other info that might help us debug this: Chain exists of: regulator_list_mutex --> regulator_ww_class_acquire --> regulator_ww_class_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(regulator_ww_class_mutex); lock(regulator_ww_class_acquire); lock(regulator_ww_class_mutex); lock(regulator_list_mutex); *** DEADLOCK *** 6 locks held by swapper/0/1: #0: ffffff8002d32188 (&dev->mutex){....}-{3:3}, at: __device_driver_lock (drivers/base/dd.c:1030) archlinux#1: ffffffc0111a0520 (cpu_hotplug_lock){++++}-{0:0}, at: cpufreq_register_driver (drivers/cpufreq/cpufreq.c:2792 (discriminator 2)) archlinux#2: ffffff8002a8d918 (subsys mutex#9){+.+.}-{3:3}, at: subsys_interface_register (drivers/base/bus.c:1033) archlinux#3: ffffff800341bb90 (&policy->rwsem){+.+.}-{3:3}, at: cpufreq_online (include/linux/bitmap.h:285 include/linux/cpumask.h:405 drivers/cpufreq/cpufreq.c:1399) archlinux#4: ffffffc011f0b7b8 (regulator_ww_class_acquire){+.+.}-{0:0}, at: regulator_enable (drivers/regulator/core.c:2808) archlinux#5: ffffff8004a77160 (regulator_ww_class_mutex){+.+.}-{3:3}, at: regulator_lock_recursive (drivers/regulator/core.c:156 drivers/regulator/core.c:263) stack backtrace: CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.14.0-rc6 archlinux#2 7c8f8996d021ed0f65271e6aeebf7999de74a9fa Hardware name: Google Scarlet (DT) Call trace: dump_backtrace (arch/arm64/kernel/stacktrace.c:161) show_stack (arch/arm64/kernel/stacktrace.c:218) dump_stack_lvl (lib/dump_stack.c:106 (discriminator 2)) dump_stack (lib/dump_stack.c:113) print_circular_bug (kernel/locking/lockdep.c:?) check_noncircular (kernel/locking/lockdep.c:?) __lock_acquire (kernel/locking/lockdep.c:3052 (discriminator 4) kernel/locking/lockdep.c:3174 (discriminator 4) kernel/locking/lockdep.c:3789 (discriminator 4) kernel/locking/lockdep.c:5015 (discriminator 4)) lock_acquire (arch/arm64/include/asm/percpu.h:39 kernel/locking/lockdep.c:438 kernel/locking/lockdep.c:5627) __mutex_lock_common (include/asm-generic/atomic-instrumented.h:606 include/asm-generic/atomic-long.h:29 kernel/locking/mutex.c:103 kernel/locking/mutex.c:144 kernel/locking/mutex.c:963) mutex_lock_nested (kernel/locking/mutex.c:1125) regulator_lock_dependent (arch/arm64/include/asm/current.h:19 include/linux/ww_mutex.h:111 drivers/regulator/core.c:329) regulator_enable (drivers/regulator/core.c:2808) vctrl_enable (drivers/regulator/vctrl-regulator.c:400) _regulator_do_enable (drivers/regulator/core.c:2617) _regulator_enable (drivers/regulator/core.c:2764) regulator_enable (drivers/regulator/core.c:308 drivers/regulator/core.c:2809) _set_opp (drivers/opp/core.c:819 drivers/opp/core.c:1072) dev_pm_opp_set_rate (drivers/opp/core.c:1164) set_target (drivers/cpufreq/cpufreq-dt.c:62) __cpufreq_driver_target (drivers/cpufreq/cpufreq.c:2216 drivers/cpufreq/cpufreq.c:2271) cpufreq_online (drivers/cpufreq/cpufreq.c:1488 (discriminator 2)) cpufreq_add_dev (drivers/cpufreq/cpufreq.c:1563) subsys_interface_register (drivers/base/bus.c:?) cpufreq_register_driver (drivers/cpufreq/cpufreq.c:2819) dt_cpufreq_probe (drivers/cpufreq/cpufreq-dt.c:344) [...] Reported-by: Brian Norris <briannorris@chromium.org> Fixes: f8702f9 ("regulator: core: Use ww_mutex for regulators locking") Fixes: e915331 ("regulator: vctrl-regulator: Avoid deadlock getting and setting the voltage") Signed-off-by: Chen-Yu Tsai <wenst@chromium.org> Link: https://lore.kernel.org/r/20210825033704.3307263-3-wenst@chromium.org Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
dmdemoura
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Oct 6, 2021
[ Upstream commit 6fa54bc ] If em28xx_ir_init fails, it would decrease the refcount of dev. However, in the em28xx_ir_fini, when ir is NULL, it goes to ref_put and decrease the refcount of dev. This will lead to a refcount bug. Fix this bug by removing the kref_put in the error handling code of em28xx_ir_init. refcount_t: underflow; use-after-free. WARNING: CPU: 0 PID: 7 at lib/refcount.c:28 refcount_warn_saturate+0x18e/0x1a0 lib/refcount.c:28 Modules linked in: CPU: 0 PID: 7 Comm: kworker/0:1 Not tainted 5.13.0 archlinux#3 Workqueue: usb_hub_wq hub_event RIP: 0010:refcount_warn_saturate+0x18e/0x1a0 lib/refcount.c:28 Call Trace: kref_put.constprop.0+0x60/0x85 include/linux/kref.h:69 em28xx_usb_disconnect.cold+0xd7/0xdc drivers/media/usb/em28xx/em28xx-cards.c:4150 usb_unbind_interface+0xbf/0x3a0 drivers/usb/core/driver.c:458 __device_release_driver drivers/base/dd.c:1201 [inline] device_release_driver_internal+0x22a/0x230 drivers/base/dd.c:1232 bus_remove_device+0x108/0x160 drivers/base/bus.c:529 device_del+0x1fe/0x510 drivers/base/core.c:3540 usb_disable_device+0xd1/0x1d0 drivers/usb/core/message.c:1419 usb_disconnect+0x109/0x330 drivers/usb/core/hub.c:2221 hub_port_connect drivers/usb/core/hub.c:5151 [inline] hub_port_connect_change drivers/usb/core/hub.c:5440 [inline] port_event drivers/usb/core/hub.c:5586 [inline] hub_event+0xf81/0x1d40 drivers/usb/core/hub.c:5668 process_one_work+0x2c9/0x610 kernel/workqueue.c:2276 process_scheduled_works kernel/workqueue.c:2338 [inline] worker_thread+0x333/0x5b0 kernel/workqueue.c:2424 kthread+0x188/0x1d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Reported-by: Dongliang Mu <mudongliangabcd@gmail.com> Fixes: ac56886 ("media: em28xx: Fix possible memory leak of em28xx struct") Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com> Signed-off-by: Sean Young <sean@mess.org> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
dmdemoura
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Oct 6, 2021
commit 13be2ef upstream. As previously noted in commit 66e4f4a ("rtc: cmos: Use spin_lock_irqsave() in cmos_interrupt()"): <4>[ 254.192378] WARNING: inconsistent lock state <4>[ 254.192384] 5.12.0-rc1-CI-CI_DRM_9834+ archlinux#1 Not tainted <4>[ 254.192396] -------------------------------- <4>[ 254.192400] inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage. <4>[ 254.192409] rtcwake/5309 [HC0[0]:SC0[0]:HE1:SE1] takes: <4>[ 254.192429] ffffffff8263c5f8 (rtc_lock){?...}-{2:2}, at: cmos_interrupt+0x18/0x100 <4>[ 254.192481] {IN-HARDIRQ-W} state was registered at: <4>[ 254.192488] lock_acquire+0xd1/0x3d0 <4>[ 254.192504] _raw_spin_lock+0x2a/0x40 <4>[ 254.192519] cmos_interrupt+0x18/0x100 <4>[ 254.192536] rtc_handler+0x1f/0xc0 <4>[ 254.192553] acpi_ev_fixed_event_detect+0x109/0x13c <4>[ 254.192574] acpi_ev_sci_xrupt_handler+0xb/0x28 <4>[ 254.192596] acpi_irq+0x13/0x30 <4>[ 254.192620] __handle_irq_event_percpu+0x43/0x2c0 <4>[ 254.192641] handle_irq_event_percpu+0x2b/0x70 <4>[ 254.192661] handle_irq_event+0x2f/0x50 <4>[ 254.192680] handle_fasteoi_irq+0x9e/0x150 <4>[ 254.192693] __common_interrupt+0x76/0x140 <4>[ 254.192715] common_interrupt+0x96/0xc0 <4>[ 254.192732] asm_common_interrupt+0x1e/0x40 <4>[ 254.192750] _raw_spin_unlock_irqrestore+0x38/0x60 <4>[ 254.192767] resume_irqs+0xba/0xf0 <4>[ 254.192786] dpm_resume_noirq+0x245/0x3d0 <4>[ 254.192811] suspend_devices_and_enter+0x230/0xaa0 <4>[ 254.192835] pm_suspend.cold.8+0x301/0x34a <4>[ 254.192859] state_store+0x7b/0xe0 <4>[ 254.192879] kernfs_fop_write_iter+0x11d/0x1c0 <4>[ 254.192899] new_sync_write+0x11d/0x1b0 <4>[ 254.192916] vfs_write+0x265/0x390 <4>[ 254.192933] ksys_write+0x5a/0xd0 <4>[ 254.192949] do_syscall_64+0x33/0x80 <4>[ 254.192965] entry_SYSCALL_64_after_hwframe+0x44/0xae <4>[ 254.192986] irq event stamp: 43775 <4>[ 254.192994] hardirqs last enabled at (43775): [<ffffffff81c00c42>] asm_sysvec_apic_timer_interrupt+0x12/0x20 <4>[ 254.193023] hardirqs last disabled at (43774): [<ffffffff81aa691a>] sysvec_apic_timer_interrupt+0xa/0xb0 <4>[ 254.193049] softirqs last enabled at (42548): [<ffffffff81e00342>] __do_softirq+0x342/0x48e <4>[ 254.193074] softirqs last disabled at (42543): [<ffffffff810b45fd>] irq_exit_rcu+0xad/0xd0 <4>[ 254.193101] other info that might help us debug this: <4>[ 254.193107] Possible unsafe locking scenario: <4>[ 254.193112] CPU0 <4>[ 254.193117] ---- <4>[ 254.193121] lock(rtc_lock); <4>[ 254.193137] <Interrupt> <4>[ 254.193142] lock(rtc_lock); <4>[ 254.193156] *** DEADLOCK *** <4>[ 254.193161] 6 locks held by rtcwake/5309: <4>[ 254.193174] #0: ffff888104861430 (sb_writers#5){.+.+}-{0:0}, at: ksys_write+0x5a/0xd0 <4>[ 254.193232] archlinux#1: ffff88810f823288 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0xe7/0x1c0 <4>[ 254.193282] archlinux#2: ffff888100cef3c0 (kn->active#285 <7>[ 254.192706] i915 0000:00:02.0: [drm:intel_modeset_setup_hw_state [i915]] [CRTC:51:pipe A] hw state readout: disabled <4>[ 254.193307] ){.+.+}-{0:0}, at: kernfs_fop_write_iter+0xf0/0x1c0 <4>[ 254.193333] archlinux#3: ffffffff82649fa8 (system_transition_mutex){+.+.}-{3:3}, at: pm_suspend.cold.8+0xce/0x34a <4>[ 254.193387] archlinux#4: ffffffff827a2108 (acpi_scan_lock){+.+.}-{3:3}, at: acpi_suspend_begin+0x47/0x70 <4>[ 254.193433] archlinux#5: ffff8881019ea178 (&dev->mutex){....}-{3:3}, at: device_resume+0x68/0x1e0 <4>[ 254.193485] stack backtrace: <4>[ 254.193492] CPU: 1 PID: 5309 Comm: rtcwake Not tainted 5.12.0-rc1-CI-CI_DRM_9834+ archlinux#1 <4>[ 254.193514] Hardware name: Google Soraka/Soraka, BIOS MrChromebox-4.10 08/25/2019 <4>[ 254.193524] Call Trace: <4>[ 254.193536] dump_stack+0x7f/0xad <4>[ 254.193567] mark_lock.part.47+0x8ca/0xce0 <4>[ 254.193604] __lock_acquire+0x39b/0x2590 <4>[ 254.193626] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 <4>[ 254.193660] lock_acquire+0xd1/0x3d0 <4>[ 254.193677] ? cmos_interrupt+0x18/0x100 <4>[ 254.193716] _raw_spin_lock+0x2a/0x40 <4>[ 254.193735] ? cmos_interrupt+0x18/0x100 <4>[ 254.193758] cmos_interrupt+0x18/0x100 <4>[ 254.193785] cmos_resume+0x2ac/0x2d0 <4>[ 254.193813] ? acpi_pm_set_device_wakeup+0x1f/0x110 <4>[ 254.193842] ? pnp_bus_suspend+0x10/0x10 <4>[ 254.193864] pnp_bus_resume+0x5e/0x90 <4>[ 254.193885] dpm_run_callback+0x5f/0x240 <4>[ 254.193914] device_resume+0xb2/0x1e0 <4>[ 254.193942] ? pm_dev_err+0x25/0x25 <4>[ 254.193974] dpm_resume+0xea/0x3f0 <4>[ 254.194005] dpm_resume_end+0x8/0x10 <4>[ 254.194030] suspend_devices_and_enter+0x29b/0xaa0 <4>[ 254.194066] pm_suspend.cold.8+0x301/0x34a <4>[ 254.194094] state_store+0x7b/0xe0 <4>[ 254.194124] kernfs_fop_write_iter+0x11d/0x1c0 <4>[ 254.194151] new_sync_write+0x11d/0x1b0 <4>[ 254.194183] vfs_write+0x265/0x390 <4>[ 254.194207] ksys_write+0x5a/0xd0 <4>[ 254.194232] do_syscall_64+0x33/0x80 <4>[ 254.194251] entry_SYSCALL_64_after_hwframe+0x44/0xae <4>[ 254.194274] RIP: 0033:0x7f07d79691e7 <4>[ 254.194293] Code: 64 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24 <4>[ 254.194312] RSP: 002b:00007ffd9cc2c768 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 <4>[ 254.194337] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f07d79691e7 <4>[ 254.194352] RDX: 0000000000000004 RSI: 0000556ebfc63590 RDI: 000000000000000b <4>[ 254.194366] RBP: 0000556ebfc63590 R08: 0000000000000000 R09: 0000000000000004 <4>[ 254.194379] R10: 0000556ebf0ec2a6 R11: 0000000000000246 R12: 0000000000000004 which breaks S3-resume on fi-kbl-soraka presumably as that's slow enough to trigger the alarm during the suspend. Fixes: 6950d04 ("rtc: cmos: Replace spin_lock_irqsave with spin_lock in hard IRQ") References: 66e4f4a ("rtc: cmos: Use spin_lock_irqsave() in cmos_interrupt()"): Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Xiaofei Tan <tanxiaofei@huawei.com> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Link: https://lore.kernel.org/r/20210305122140.28774-1-chris@chris-wilson.co.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 57f0ff0 upstream. It's later supposed to be either a correct address or NULL. Without the initialization, it may contain an undefined value which results in the following segmentation fault: # perf top --sort comm -g --ignore-callees=do_idle terminates with: #0 0x00007ffff56b7685 in __strlen_avx2 () from /lib64/libc.so.6 archlinux#1 0x00007ffff55e3802 in strdup () from /lib64/libc.so.6 archlinux#2 0x00005555558cb139 in hist_entry__init (callchain_size=<optimized out>, sample_self=true, template=0x7fffde7fb110, he=0x7fffd801c250) at util/hist.c:489 archlinux#3 hist_entry__new (template=template@entry=0x7fffde7fb110, sample_self=sample_self@entry=true) at util/hist.c:564 archlinux#4 0x00005555558cb4ba in hists__findnew_entry (hists=hists@entry=0x5555561d9e38, entry=entry@entry=0x7fffde7fb110, al=al@entry=0x7fffde7fb420, sample_self=sample_self@entry=true) at util/hist.c:657 archlinux#5 0x00005555558cba1b in __hists__add_entry (hists=hists@entry=0x5555561d9e38, al=0x7fffde7fb420, sym_parent=<optimized out>, bi=bi@entry=0x0, mi=mi@entry=0x0, sample=sample@entry=0x7fffde7fb4b0, sample_self=true, ops=0x0, block_info=0x0) at util/hist.c:288 archlinux#6 0x00005555558cbb70 in hists__add_entry (sample_self=true, sample=0x7fffde7fb4b0, mi=0x0, bi=0x0, sym_parent=<optimized out>, al=<optimized out>, hists=0x5555561d9e38) at util/hist.c:1056 archlinux#7 iter_add_single_cumulative_entry (iter=0x7fffde7fb460, al=<optimized out>) at util/hist.c:1056 archlinux#8 0x00005555558cc8a4 in hist_entry_iter__add (iter=iter@entry=0x7fffde7fb460, al=al@entry=0x7fffde7fb420, max_stack_depth=<optimized out>, arg=arg@entry=0x7fffffff7db0) at util/hist.c:1231 archlinux#9 0x00005555557cdc9a in perf_event__process_sample (machine=<optimized out>, sample=0x7fffde7fb4b0, evsel=<optimized out>, event=<optimized out>, tool=0x7fffffff7db0) at builtin-top.c:842 torvalds#10 deliver_event (qe=<optimized out>, qevent=<optimized out>) at builtin-top.c:1202 torvalds#11 0x00005555558a9318 in do_flush (show_progress=false, oe=0x7fffffff80e0) at util/ordered-events.c:244 torvalds#12 __ordered_events__flush (oe=oe@entry=0x7fffffff80e0, how=how@entry=OE_FLUSH__TOP, timestamp=timestamp@entry=0) at util/ordered-events.c:323 torvalds#13 0x00005555558a9789 in __ordered_events__flush (timestamp=<optimized out>, how=<optimized out>, oe=<optimized out>) at util/ordered-events.c:339 torvalds#14 ordered_events__flush (how=OE_FLUSH__TOP, oe=0x7fffffff80e0) at util/ordered-events.c:341 torvalds#15 ordered_events__flush (oe=oe@entry=0x7fffffff80e0, how=how@entry=OE_FLUSH__TOP) at util/ordered-events.c:339 torvalds#16 0x00005555557cd631 in process_thread (arg=0x7fffffff7db0) at builtin-top.c:1114 torvalds#17 0x00007ffff7bb817a in start_thread () from /lib64/libpthread.so.0 torvalds#18 0x00007ffff5656dc3 in clone () from /lib64/libc.so.6 If you look at the frame archlinux#2, the code is: 488 if (he->srcline) { 489 he->srcline = strdup(he->srcline); 490 if (he->srcline == NULL) 491 goto err_rawdata; 492 } If he->srcline is not NULL (it is not NULL if it is uninitialized rubbish), it gets strdupped and strdupping a rubbish random string causes the problem. Also, if you look at the commit 1fb7d06, it adds the srcline property into the struct, but not initializing it everywhere needed. Committer notes: Now I see, when using --ignore-callees=do_idle we end up here at line 2189 in add_callchain_ip(): 2181 if (al.sym != NULL) { 2182 if (perf_hpp_list.parent && !*parent && 2183 symbol__match_regex(al.sym, &parent_regex)) 2184 *parent = al.sym; 2185 else if (have_ignore_callees && root_al && 2186 symbol__match_regex(al.sym, &ignore_callees_regex)) { 2187 /* Treat this symbol as the root, 2188 forgetting its callees. */ 2189 *root_al = al; 2190 callchain_cursor_reset(cursor); 2191 } 2192 } And the al that doesn't have the ->srcline field initialized will be copied to the root_al, so then, back to: 1211 int hist_entry_iter__add(struct hist_entry_iter *iter, struct addr_location *al, 1212 int max_stack_depth, void *arg) 1213 { 1214 int err, err2; 1215 struct map *alm = NULL; 1216 1217 if (al) 1218 alm = map__get(al->map); 1219 1220 err = sample__resolve_callchain(iter->sample, &callchain_cursor, &iter->parent, 1221 iter->evsel, al, max_stack_depth); 1222 if (err) { 1223 map__put(alm); 1224 return err; 1225 } 1226 1227 err = iter->ops->prepare_entry(iter, al); 1228 if (err) 1229 goto out; 1230 1231 err = iter->ops->add_single_entry(iter, al); 1232 if (err) 1233 goto out; 1234 That al at line 1221 is what hist_entry_iter__add() (called from sample__resolve_callchain()) saw as 'root_al', and then: iter->ops->add_single_entry(iter, al); will go on with al->srcline with a bogus value, I'll add the above sequence to the cset and apply, thanks! Signed-off-by: Michael Petlan <mpetlan@redhat.com> CC: Milian Wolff <milian.wolff@kdab.com> Cc: Jiri Olsa <jolsa@redhat.com> Fixes: 1fb7d06 ("perf report Use srcline from callchain for hist entries") Link: https //lore.kernel.org/r/20210719145332.29747-1-mpetlan@redhat.com Reported-by: Juri Lelli <jlelli@redhat.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 340fa66 ] Recent changes exposed a bug where specifically-timed requests to the path manager netlink API could trigger a divide-by-zero in __tcp_select_window(), as syzkaller does: divide error: 0000 [archlinux#1] SMP KASAN NOPTI CPU: 0 PID: 9667 Comm: syz-executor.0 Not tainted 5.14.0-rc6+ archlinux#3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 RIP: 0010:__tcp_select_window+0x509/0xa60 net/ipv4/tcp_output.c:3016 Code: 44 89 ff e8 c9 29 e9 fd 45 39 e7 0f 8d 20 ff ff ff e8 db 28 e9 fd 44 89 e3 e9 13 ff ff ff e8 ce 28 e9 fd 44 89 e0 44 89 e3 99 <f7> 7c 24 04 29 d3 e9 fc fe ff ff e8 b7 28 e9 fd 44 89 f1 48 89 ea RSP: 0018:ffff888031ccf020 EFLAGS: 00010216 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000040000 RDX: 0000000000000000 RSI: ffff88811532c080 RDI: 0000000000000002 RBP: 0000000000000000 R08: ffffffff835807c2 R09: 0000000000000000 R10: 0000000000000004 R11: ffffed1020b92441 R12: 0000000000000000 R13: 1ffff11006399e08 R14: 0000000000000000 R15: 0000000000000000 FS: 00007fa4c8344700(0000) GS:ffff88811ae00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2f424000 CR3: 000000003e4e2003 CR4: 0000000000770ef0 PKRU: 55555554 Call Trace: tcp_select_window net/ipv4/tcp_output.c:264 [inline] __tcp_transmit_skb+0xc00/0x37a0 net/ipv4/tcp_output.c:1351 __tcp_send_ack.part.0+0x3ec/0x760 net/ipv4/tcp_output.c:3972 __tcp_send_ack net/ipv4/tcp_output.c:3978 [inline] tcp_send_ack+0x7d/0xa0 net/ipv4/tcp_output.c:3978 mptcp_pm_nl_addr_send_ack+0x1ab/0x380 net/mptcp/pm_netlink.c:654 mptcp_pm_remove_addr+0x161/0x200 net/mptcp/pm.c:58 mptcp_nl_remove_id_zero_address+0x197/0x460 net/mptcp/pm_netlink.c:1328 mptcp_nl_cmd_del_addr+0x98b/0xd40 net/mptcp/pm_netlink.c:1359 genl_family_rcv_msg_doit.isra.0+0x225/0x340 net/netlink/genetlink.c:731 genl_family_rcv_msg net/netlink/genetlink.c:775 [inline] genl_rcv_msg+0x341/0x5b0 net/netlink/genetlink.c:792 netlink_rcv_skb+0x148/0x430 net/netlink/af_netlink.c:2504 genl_rcv+0x24/0x40 net/netlink/genetlink.c:803 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x537/0x750 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x846/0xd80 net/netlink/af_netlink.c:1929 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg+0x14e/0x190 net/socket.c:724 ____sys_sendmsg+0x709/0x870 net/socket.c:2403 ___sys_sendmsg+0xff/0x170 net/socket.c:2457 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2486 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae mptcp_pm_nl_addr_send_ack() was attempting to send a TCP ACK on the first subflow in the MPTCP socket's connection list without validating that the subflow was in a suitable connection state. To address this, always validate subflow state when sending extra ACKs on subflows for address advertisement or subflow priority change. Fixes: 84dfe36 ("mptcp: send out dedicated ADD_ADDR packet") Closes: multipath-tcp/mptcp_net-next#229 Co-developed-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Acked-by: Geliang Tang <geliangtang@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit 98e2e40 upstream. When the refcount is decreased to 0, the resource reclamation branch is entered. Before CPU0 reaches the race point (1), CPU1 may obtain the spinlock and traverse the rbtree to find 'root', see nilfs_lookup_root(). Although CPU1 will call refcount_inc() to increase the refcount, it is obviously too late. CPU0 will release 'root' directly, CPU1 then accesses 'root' and triggers UAF. Use refcount_dec_and_lock() to ensure that both the operations of decrease refcount to 0 and link deletion are lock protected eliminates this risk. CPU0 CPU1 nilfs_put_root(): <-------- (1) spin_lock(&nilfs->ns_cptree_lock); rb_erase(&root->rb_node, &nilfs->ns_cptree); spin_unlock(&nilfs->ns_cptree_lock); kfree(root); <-------- use-after-free refcount_t: underflow; use-after-free. WARNING: CPU: 2 PID: 9476 at lib/refcount.c:28 \ refcount_warn_saturate+0x1cf/0x210 lib/refcount.c:28 Modules linked in: CPU: 2 PID: 9476 Comm: syz-executor.0 Not tainted 5.10.45-rc1+ archlinux#3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), ... RIP: 0010:refcount_warn_saturate+0x1cf/0x210 lib/refcount.c:28 ... ... Call Trace: __refcount_sub_and_test include/linux/refcount.h:283 [inline] __refcount_dec_and_test include/linux/refcount.h:315 [inline] refcount_dec_and_test include/linux/refcount.h:333 [inline] nilfs_put_root+0xc1/0xd0 fs/nilfs2/the_nilfs.c:795 nilfs_segctor_destroy fs/nilfs2/segment.c:2749 [inline] nilfs_detach_log_writer+0x3fa/0x570 fs/nilfs2/segment.c:2812 nilfs_put_super+0x2f/0xf0 fs/nilfs2/super.c:467 generic_shutdown_super+0xcd/0x1f0 fs/super.c:464 kill_block_super+0x4a/0x90 fs/super.c:1446 deactivate_locked_super+0x6a/0xb0 fs/super.c:335 deactivate_super+0x85/0x90 fs/super.c:366 cleanup_mnt+0x277/0x2e0 fs/namespace.c:1118 __cleanup_mnt+0x15/0x20 fs/namespace.c:1125 task_work_run+0x8e/0x110 kernel/task_work.c:151 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop kernel/entry/common.c:164 [inline] exit_to_user_mode_prepare+0x13c/0x170 kernel/entry/common.c:191 syscall_exit_to_user_mode+0x16/0x30 kernel/entry/common.c:266 do_syscall_64+0x45/0x80 arch/x86/entry/common.c:56 entry_SYSCALL_64_after_hwframe+0x44/0xa9 There is no reproduction program, and the above is only theoretical analysis. Link: https://lkml.kernel.org/r/1629859428-5906-1-git-send-email-konishi.ryusuke@gmail.com Fixes: ba65ae4 ("nilfs2: add checkpoint tree to nilfs object") Link: https://lkml.kernel.org/r/20210723012317.4146-1-thunder.leizhen@huawei.com Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 8f96a5b ] We update the ctime/mtime of a block device when we remove it so that blkid knows the device changed. However we do this by re-opening the block device and calling filp_update_time. This is more correct because it'll call the inode->i_op->update_time if it exists, but the block dev inodes do not do this. Instead call generic_update_time() on the bd_inode in order to avoid the blkdev_open path and get rid of the following lockdep splat: ====================================================== WARNING: possible circular locking dependency detected 5.14.0-rc2+ torvalds#406 Not tainted ------------------------------------------------------ losetup/11596 is trying to acquire lock: ffff939640d2f538 ((wq_completion)loop0){+.+.}-{0:0}, at: flush_workqueue+0x67/0x5e0 but task is already holding lock: ffff939655510c68 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x660 [loop] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> archlinux#4 (&lo->lo_mutex){+.+.}-{3:3}: __mutex_lock+0x7d/0x750 lo_open+0x28/0x60 [loop] blkdev_get_whole+0x25/0xf0 blkdev_get_by_dev.part.0+0x168/0x3c0 blkdev_open+0xd2/0xe0 do_dentry_open+0x161/0x390 path_openat+0x3cc/0xa20 do_filp_open+0x96/0x120 do_sys_openat2+0x7b/0x130 __x64_sys_openat+0x46/0x70 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae -> archlinux#3 (&disk->open_mutex){+.+.}-{3:3}: __mutex_lock+0x7d/0x750 blkdev_get_by_dev.part.0+0x56/0x3c0 blkdev_open+0xd2/0xe0 do_dentry_open+0x161/0x390 path_openat+0x3cc/0xa20 do_filp_open+0x96/0x120 file_open_name+0xc7/0x170 filp_open+0x2c/0x50 btrfs_scratch_superblocks.part.0+0x10f/0x170 btrfs_rm_device.cold+0xe8/0xed btrfs_ioctl+0x2a31/0x2e70 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae -> archlinux#2 (sb_writers#12){.+.+}-{0:0}: lo_write_bvec+0xc2/0x240 [loop] loop_process_work+0x238/0xd00 [loop] process_one_work+0x26b/0x560 worker_thread+0x55/0x3c0 kthread+0x140/0x160 ret_from_fork+0x1f/0x30 -> archlinux#1 ((work_completion)(&lo->rootcg_work)){+.+.}-{0:0}: process_one_work+0x245/0x560 worker_thread+0x55/0x3c0 kthread+0x140/0x160 ret_from_fork+0x1f/0x30 -> #0 ((wq_completion)loop0){+.+.}-{0:0}: __lock_acquire+0x10ea/0x1d90 lock_acquire+0xb5/0x2b0 flush_workqueue+0x91/0x5e0 drain_workqueue+0xa0/0x110 destroy_workqueue+0x36/0x250 __loop_clr_fd+0x9a/0x660 [loop] block_ioctl+0x3f/0x50 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae other info that might help us debug this: Chain exists of: (wq_completion)loop0 --> &disk->open_mutex --> &lo->lo_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&lo->lo_mutex); lock(&disk->open_mutex); lock(&lo->lo_mutex); lock((wq_completion)loop0); *** DEADLOCK *** 1 lock held by losetup/11596: #0: ffff939655510c68 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x660 [loop] stack backtrace: CPU: 1 PID: 11596 Comm: losetup Not tainted 5.14.0-rc2+ torvalds#406 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014 Call Trace: dump_stack_lvl+0x57/0x72 check_noncircular+0xcf/0xf0 ? stack_trace_save+0x3b/0x50 __lock_acquire+0x10ea/0x1d90 lock_acquire+0xb5/0x2b0 ? flush_workqueue+0x67/0x5e0 ? lockdep_init_map_type+0x47/0x220 flush_workqueue+0x91/0x5e0 ? flush_workqueue+0x67/0x5e0 ? verify_cpu+0xf0/0x100 drain_workqueue+0xa0/0x110 destroy_workqueue+0x36/0x250 __loop_clr_fd+0x9a/0x660 [loop] ? blkdev_ioctl+0x8d/0x2a0 block_ioctl+0x3f/0x50 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 3fa421d ] When removing the device we call blkdev_put() on the device once we've removed it, and because we have an EXCL open we need to take the ->open_mutex on the block device to clean it up. Unfortunately during device remove we are holding the sb writers lock, which results in the following lockdep splat: ====================================================== WARNING: possible circular locking dependency detected 5.14.0-rc2+ torvalds#407 Not tainted ------------------------------------------------------ losetup/11595 is trying to acquire lock: ffff973ac35dd138 ((wq_completion)loop0){+.+.}-{0:0}, at: flush_workqueue+0x67/0x5e0 but task is already holding lock: ffff973ac9812c68 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x660 [loop] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> archlinux#4 (&lo->lo_mutex){+.+.}-{3:3}: __mutex_lock+0x7d/0x750 lo_open+0x28/0x60 [loop] blkdev_get_whole+0x25/0xf0 blkdev_get_by_dev.part.0+0x168/0x3c0 blkdev_open+0xd2/0xe0 do_dentry_open+0x161/0x390 path_openat+0x3cc/0xa20 do_filp_open+0x96/0x120 do_sys_openat2+0x7b/0x130 __x64_sys_openat+0x46/0x70 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae -> archlinux#3 (&disk->open_mutex){+.+.}-{3:3}: __mutex_lock+0x7d/0x750 blkdev_put+0x3a/0x220 btrfs_rm_device.cold+0x62/0xe5 btrfs_ioctl+0x2a31/0x2e70 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae -> archlinux#2 (sb_writers#12){.+.+}-{0:0}: lo_write_bvec+0xc2/0x240 [loop] loop_process_work+0x238/0xd00 [loop] process_one_work+0x26b/0x560 worker_thread+0x55/0x3c0 kthread+0x140/0x160 ret_from_fork+0x1f/0x30 -> archlinux#1 ((work_completion)(&lo->rootcg_work)){+.+.}-{0:0}: process_one_work+0x245/0x560 worker_thread+0x55/0x3c0 kthread+0x140/0x160 ret_from_fork+0x1f/0x30 -> #0 ((wq_completion)loop0){+.+.}-{0:0}: __lock_acquire+0x10ea/0x1d90 lock_acquire+0xb5/0x2b0 flush_workqueue+0x91/0x5e0 drain_workqueue+0xa0/0x110 destroy_workqueue+0x36/0x250 __loop_clr_fd+0x9a/0x660 [loop] block_ioctl+0x3f/0x50 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae other info that might help us debug this: Chain exists of: (wq_completion)loop0 --> &disk->open_mutex --> &lo->lo_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&lo->lo_mutex); lock(&disk->open_mutex); lock(&lo->lo_mutex); lock((wq_completion)loop0); *** DEADLOCK *** 1 lock held by losetup/11595: #0: ffff973ac9812c68 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x660 [loop] stack backtrace: CPU: 0 PID: 11595 Comm: losetup Not tainted 5.14.0-rc2+ torvalds#407 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014 Call Trace: dump_stack_lvl+0x57/0x72 check_noncircular+0xcf/0xf0 ? stack_trace_save+0x3b/0x50 __lock_acquire+0x10ea/0x1d90 lock_acquire+0xb5/0x2b0 ? flush_workqueue+0x67/0x5e0 ? lockdep_init_map_type+0x47/0x220 flush_workqueue+0x91/0x5e0 ? flush_workqueue+0x67/0x5e0 ? verify_cpu+0xf0/0x100 drain_workqueue+0xa0/0x110 destroy_workqueue+0x36/0x250 __loop_clr_fd+0x9a/0x660 [loop] ? blkdev_ioctl+0x8d/0x2a0 block_ioctl+0x3f/0x50 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fc21255d4cb So instead save the bdev and do the put once we've dropped the sb writers lock in order to avoid the lockdep recursion. Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit dfbb340 ] If CONFIG_BLK_DEV_LOOP && CONFIG_MTD (at least; there might be other combinations), lockdep complains circular locking dependency at __loop_clr_fd(), for major_names_lock serves as a locking dependency aggregating hub across multiple block modules. ====================================================== WARNING: possible circular locking dependency detected 5.14.0+ torvalds#757 Tainted: G E ------------------------------------------------------ systemd-udevd/7568 is trying to acquire lock: ffff88800f334d48 ((wq_completion)loop0){+.+.}-{0:0}, at: flush_workqueue+0x70/0x560 but task is already holding lock: ffff888014a7d4a0 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x4d/0x400 [loop] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> archlinux#6 (&lo->lo_mutex){+.+.}-{3:3}: lock_acquire+0xbe/0x1f0 __mutex_lock_common+0xb6/0xe10 mutex_lock_killable_nested+0x17/0x20 lo_open+0x23/0x50 [loop] blkdev_get_by_dev+0x199/0x540 blkdev_open+0x58/0x90 do_dentry_open+0x144/0x3a0 path_openat+0xa57/0xda0 do_filp_open+0x9f/0x140 do_sys_openat2+0x71/0x150 __x64_sys_openat+0x78/0xa0 do_syscall_64+0x3d/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae -> archlinux#5 (&disk->open_mutex){+.+.}-{3:3}: lock_acquire+0xbe/0x1f0 __mutex_lock_common+0xb6/0xe10 mutex_lock_nested+0x17/0x20 bd_register_pending_holders+0x20/0x100 device_add_disk+0x1ae/0x390 loop_add+0x29c/0x2d0 [loop] blk_request_module+0x5a/0xb0 blkdev_get_no_open+0x27/0xa0 blkdev_get_by_dev+0x5f/0x540 blkdev_open+0x58/0x90 do_dentry_open+0x144/0x3a0 path_openat+0xa57/0xda0 do_filp_open+0x9f/0x140 do_sys_openat2+0x71/0x150 __x64_sys_openat+0x78/0xa0 do_syscall_64+0x3d/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae -> archlinux#4 (major_names_lock){+.+.}-{3:3}: lock_acquire+0xbe/0x1f0 __mutex_lock_common+0xb6/0xe10 mutex_lock_nested+0x17/0x20 blkdev_show+0x19/0x80 devinfo_show+0x52/0x60 seq_read_iter+0x2d5/0x3e0 proc_reg_read_iter+0x41/0x80 vfs_read+0x2ac/0x330 ksys_read+0x6b/0xd0 do_syscall_64+0x3d/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae -> archlinux#3 (&p->lock){+.+.}-{3:3}: lock_acquire+0xbe/0x1f0 __mutex_lock_common+0xb6/0xe10 mutex_lock_nested+0x17/0x20 seq_read_iter+0x37/0x3e0 generic_file_splice_read+0xf3/0x170 splice_direct_to_actor+0x14e/0x350 do_splice_direct+0x84/0xd0 do_sendfile+0x263/0x430 __se_sys_sendfile64+0x96/0xc0 do_syscall_64+0x3d/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae -> archlinux#2 (sb_writers#3){.+.+}-{0:0}: lock_acquire+0xbe/0x1f0 lo_write_bvec+0x96/0x280 [loop] loop_process_work+0xa68/0xc10 [loop] process_one_work+0x293/0x480 worker_thread+0x23d/0x4b0 kthread+0x163/0x180 ret_from_fork+0x1f/0x30 -> archlinux#1 ((work_completion)(&lo->rootcg_work)){+.+.}-{0:0}: lock_acquire+0xbe/0x1f0 process_one_work+0x280/0x480 worker_thread+0x23d/0x4b0 kthread+0x163/0x180 ret_from_fork+0x1f/0x30 -> #0 ((wq_completion)loop0){+.+.}-{0:0}: validate_chain+0x1f0d/0x33e0 __lock_acquire+0x92d/0x1030 lock_acquire+0xbe/0x1f0 flush_workqueue+0x8c/0x560 drain_workqueue+0x80/0x140 destroy_workqueue+0x47/0x4f0 __loop_clr_fd+0xb4/0x400 [loop] blkdev_put+0x14a/0x1d0 blkdev_close+0x1c/0x20 __fput+0xfd/0x220 task_work_run+0x69/0xc0 exit_to_user_mode_prepare+0x1ce/0x1f0 syscall_exit_to_user_mode+0x26/0x60 do_syscall_64+0x4c/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae other info that might help us debug this: Chain exists of: (wq_completion)loop0 --> &disk->open_mutex --> &lo->lo_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&lo->lo_mutex); lock(&disk->open_mutex); lock(&lo->lo_mutex); lock((wq_completion)loop0); *** DEADLOCK *** 2 locks held by systemd-udevd/7568: #0: ffff888012554128 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0x4c/0x1d0 archlinux#1: ffff888014a7d4a0 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x4d/0x400 [loop] stack backtrace: CPU: 0 PID: 7568 Comm: systemd-udevd Tainted: G E 5.14.0+ torvalds#757 Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 02/27/2020 Call Trace: dump_stack_lvl+0x79/0xbf print_circular_bug+0x5d6/0x5e0 ? stack_trace_save+0x42/0x60 ? save_trace+0x3d/0x2d0 check_noncircular+0x10b/0x120 validate_chain+0x1f0d/0x33e0 ? __lock_acquire+0x953/0x1030 ? __lock_acquire+0x953/0x1030 __lock_acquire+0x92d/0x1030 ? flush_workqueue+0x70/0x560 lock_acquire+0xbe/0x1f0 ? flush_workqueue+0x70/0x560 flush_workqueue+0x8c/0x560 ? flush_workqueue+0x70/0x560 ? sched_clock_cpu+0xe/0x1a0 ? drain_workqueue+0x41/0x140 drain_workqueue+0x80/0x140 destroy_workqueue+0x47/0x4f0 ? blk_mq_freeze_queue_wait+0xac/0xd0 __loop_clr_fd+0xb4/0x400 [loop] ? __mutex_unlock_slowpath+0x35/0x230 blkdev_put+0x14a/0x1d0 blkdev_close+0x1c/0x20 __fput+0xfd/0x220 task_work_run+0x69/0xc0 exit_to_user_mode_prepare+0x1ce/0x1f0 syscall_exit_to_user_mode+0x26/0x60 do_syscall_64+0x4c/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f0fd4c661f7 Code: 00 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 41 c3 48 83 ec 18 89 7c 24 0c e8 13 fc ff ff RSP: 002b:00007ffd1c9e9fd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 00007f0fd46be6c8 RCX: 00007f0fd4c661f7 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000006 RBP: 0000000000000006 R08: 000055fff1eaf400 R09: 0000000000000000 R10: 00007f0fd46be6c8 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000002f08 R15: 00007ffd1c9ea050 Commit 1c500ad ("loop: reduce the loop_ctl_mutex scope") is for breaking "loop_ctl_mutex => &lo->lo_mutex" dependency chain. But enabling a different block module results in forming circular locking dependency due to shared major_names_lock mutex. The simplest fix is to call probe function without holding major_names_lock [1], but Christoph Hellwig does not like such idea. Therefore, instead of holding major_names_lock in blkdev_show(), introduce a different lock for blkdev_show() in order to break "sb_writers#$N => &p->lock => major_names_lock" dependency chain. Link: https://lkml.kernel.org/r/b2af8a5b-3c1b-204e-7f56-bea0b15848d6@i-love.sakura.ne.jp [1] Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Link: https://lore.kernel.org/r/18a02da2-0bf3-550e-b071-2b4ab13c49f0@i-love.sakura.ne.jp Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit aba5dae ] FD uses xyarray__entry that may return NULL if an index is out of bounds. If NULL is returned then a segv happens as FD unconditionally dereferences the pointer. This was happening in a case of with perf iostat as shown below. The fix is to make FD an "int*" rather than an int and handle the NULL case as either invalid input or a closed fd. $ sudo gdb --args perf stat --iostat list ... Breakpoint 1, perf_evsel__alloc_fd (evsel=0x5555560951a0, ncpus=1, nthreads=1) at evsel.c:50 50 { (gdb) bt #0 perf_evsel__alloc_fd (evsel=0x5555560951a0, ncpus=1, nthreads=1) at evsel.c:50 archlinux#1 0x000055555585c188 in evsel__open_cpu (evsel=0x5555560951a0, cpus=0x555556093410, threads=0x555556086fb0, start_cpu=0, end_cpu=1) at util/evsel.c:1792 archlinux#2 0x000055555585cfb2 in evsel__open (evsel=0x5555560951a0, cpus=0x0, threads=0x555556086fb0) at util/evsel.c:2045 archlinux#3 0x000055555585d0db in evsel__open_per_thread (evsel=0x5555560951a0, threads=0x555556086fb0) at util/evsel.c:2065 archlinux#4 0x00005555558ece64 in create_perf_stat_counter (evsel=0x5555560951a0, config=0x555555c34700 <stat_config>, target=0x555555c2f1c0 <target>, cpu=0) at util/stat.c:590 archlinux#5 0x000055555578e927 in __run_perf_stat (argc=1, argv=0x7fffffffe4a0, run_idx=0) at builtin-stat.c:833 archlinux#6 0x000055555578f3c6 in run_perf_stat (argc=1, argv=0x7fffffffe4a0, run_idx=0) at builtin-stat.c:1048 archlinux#7 0x0000555555792ee5 in cmd_stat (argc=1, argv=0x7fffffffe4a0) at builtin-stat.c:2534 archlinux#8 0x0000555555835ed3 in run_builtin (p=0x555555c3f540 <commands+288>, argc=3, argv=0x7fffffffe4a0) at perf.c:313 archlinux#9 0x0000555555836154 in handle_internal_command (argc=3, argv=0x7fffffffe4a0) at perf.c:365 torvalds#10 0x000055555583629f in run_argv (argcp=0x7fffffffe2ec, argv=0x7fffffffe2e0) at perf.c:409 torvalds#11 0x0000555555836692 in main (argc=3, argv=0x7fffffffe4a0) at perf.c:539 ... (gdb) c Continuing. Error: The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (uncore_iio_0/event=0x83,umask=0x04,ch_mask=0xF,fc_mask=0x07/). /bin/dmesg | grep -i perf may provide additional information. Program received signal SIGSEGV, Segmentation fault. 0x00005555559b03ea in perf_evsel__close_fd_cpu (evsel=0x5555560951a0, cpu=1) at evsel.c:166 166 if (FD(evsel, cpu, thread) >= 0) v3. fixes a bug in perf_evsel__run_ioctl where the sense of a branch was backward. Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lore.kernel.org/lkml/20210918054440.2350466-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
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Pablo Neira Ayuso says: ==================== Netfilter fixes for net (v2) The following patchset contains Netfilter fixes for net: 1) Move back the defrag users fields to the global netns_nf area. Kernel fails to boot if conntrack is builtin and kernel is booted with: nf_conntrack.enable_hooks=1. From Florian Westphal. 2) Rule event notification is missing relevant context such as the position handle and the NLM_F_APPEND flag. 3) Rule replacement is expanded to add + delete using the existing rule handle, reverse order of this operation so it makes sense from rule notification standpoint. 4) Propagate to userspace the NLM_F_CREATE and NLM_F_EXCL flags from the rule notification path. Patches #2, #3 and #4 are used by 'nft monitor' and 'iptables-monitor' userspace utilities which are not correctly representing the following operations through netlink notifications: - rule insertions - rule addition/insertion from position handle - create table/chain/set/map/flowtable/... ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
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Oct 10, 2021
When passing 'phys' in the devicetree to describe the USB PHY phandle (which is the recommended way according to Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt) the following NULL pointer dereference is observed on i.MX7 and i.MX8MM: [ 1.489344] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000098 [ 1.498170] Mem abort info: [ 1.500966] ESR = 0x96000044 [ 1.504030] EC = 0x25: DABT (current EL), IL = 32 bits [ 1.509356] SET = 0, FnV = 0 [ 1.512416] EA = 0, S1PTW = 0 [ 1.515569] FSC = 0x04: level 0 translation fault [ 1.520458] Data abort info: [ 1.523349] ISV = 0, ISS = 0x00000044 [ 1.527196] CM = 0, WnR = 1 [ 1.530176] [0000000000000098] user address but active_mm is swapper [ 1.536544] Internal error: Oops: 96000044 [#1] PREEMPT SMP [ 1.542125] Modules linked in: [ 1.545190] CPU: 3 PID: 7 Comm: kworker/u8:0 Not tainted 5.14.0-dirty #3 [ 1.551901] Hardware name: Kontron i.MX8MM N801X S (DT) [ 1.557133] Workqueue: events_unbound deferred_probe_work_func [ 1.562984] pstate: 80000005 (Nzcv daif -PAN -UAO -TCO BTYPE=--) [ 1.568998] pc : imx7d_charger_detection+0x3f0/0x510 [ 1.573973] lr : imx7d_charger_detection+0x22c/0x510 This happens because the charger functions check for the phy presence inside the imx_usbmisc_data structure (data->usb_phy), but the chipidea core populates the usb_phy passed via 'phys' inside 'struct ci_hdrc' (ci->usb_phy) instead. This causes the NULL pointer dereference inside imx7d_charger_detection(). Fix it by also searching for 'phys' in case 'fsl,usbphy' is not found. Tested on a imx7s-warp board. Fixes: 746f316 ("usb: chipidea: introduce imx7d USB charger detection") Cc: stable@vger.kernel.org Reported-by: Heiko Thiery <heiko.thiery@gmail.com> Tested-by: Frieder Schrempf <frieder.schrempf@kontron.de> Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de> Acked-by: Peter Chen <peter.chen@kernel.org> Signed-off-by: Fabio Estevam <festevam@gmail.com> Link: https://lore.kernel.org/r/20210921113754.767631-1-festevam@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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…rbage value
Currently, when the rule related to IDLETIMER is added, idletimer_tg timer
structure is initialized by kmalloc on executing idletimer_tg_create
function. However, in this process timer->timer_type is not defined to
a specific value. Thus, timer->timer_type has garbage value and it occurs
kernel panic. So, this commit fixes the panic by initializing
timer->timer_type using kzalloc instead of kmalloc.
Test commands:
# iptables -A OUTPUT -j IDLETIMER --timeout 1 --label test
$ cat /sys/class/xt_idletimer/timers/test
Killed
Splat looks like:
BUG: KASAN: user-memory-access in alarm_expires_remaining+0x49/0x70
Read of size 8 at addr 0000002e8c7bc4c8 by task cat/917
CPU: 12 PID: 917 Comm: cat Not tainted 5.14.0+ #3 79940a339f71eb14fc81aee1757a20d5bf13eb0e
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-1ubuntu1.1 04/01/2014
Call Trace:
dump_stack_lvl+0x6e/0x9c
kasan_report.cold+0x112/0x117
? alarm_expires_remaining+0x49/0x70
__asan_load8+0x86/0xb0
alarm_expires_remaining+0x49/0x70
idletimer_tg_show+0xe5/0x19b [xt_IDLETIMER 11219304af9316a21bee5ba9d58f76a6b9bccc6d]
dev_attr_show+0x3c/0x60
sysfs_kf_seq_show+0x11d/0x1f0
? device_remove_bin_file+0x20/0x20
kernfs_seq_show+0xa4/0xb0
seq_read_iter+0x29c/0x750
kernfs_fop_read_iter+0x25a/0x2c0
? __fsnotify_parent+0x3d1/0x570
? iov_iter_init+0x70/0x90
new_sync_read+0x2a7/0x3d0
? __x64_sys_llseek+0x230/0x230
? rw_verify_area+0x81/0x150
vfs_read+0x17b/0x240
ksys_read+0xd9/0x180
? vfs_write+0x460/0x460
? do_syscall_64+0x16/0xc0
? lockdep_hardirqs_on+0x79/0x120
__x64_sys_read+0x43/0x50
do_syscall_64+0x3b/0xc0
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f0cdc819142
Code: c0 e9 c2 fe ff ff 50 48 8d 3d 3a ca 0a 00 e8 f5 19 02 00 0f 1f 44 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 0f 05 <48> 3d 00 f0 ff ff 77 56 c3 0f 1f 44 00 00 48 83 ec 28 48 89 54 24
RSP: 002b:00007fff28eee5b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007f0cdc819142
RDX: 0000000000020000 RSI: 00007f0cdc032000 RDI: 0000000000000003
RBP: 00007f0cdc032000 R08: 00007f0cdc031010 R09: 0000000000000000
R10: 0000000000000022 R11: 0000000000000246 R12: 00005607e9ee31f0
R13: 0000000000000003 R14: 0000000000020000 R15: 0000000000020000
Fixes: 68983a3 ("netfilter: xtables: Add snapshot of hardidletimer target")
Signed-off-by: Juhee Kang <claudiajkang@gmail.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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Convert the 9p filesystem to use the netfs helper lib to handle readpage, readahead and write_begin, converting those into a common issue_op for the filesystem itself to handle. The netfs helper lib also handles reading from fscache if a cache is available, and interleaving reads from both sources. This change also switches from the old fscache I/O API to the new one, meaning that fscache no longer keeps track of netfs pages and instead does async DIO between the backing files and the 9p file pagecache. As a part of this change, the handling of PG_fscache changes. It now just means that the cache has a write I/O operation in progress on a page (PG_locked is used for a read I/O op). Note that this is a cut-down version of the fscache rewrite and does not change any of the cookie and cache coherency handling. Changes ======= ver #4: - Rebase on top of folios. - Don't use wait_on_page_bit_killable(). ver #3: - v9fs_req_issue_op() needs to terminate the subrequest. - v9fs_write_end() needs to call SetPageUptodate() a bit more often. - It's not CONFIG_{AFS,V9FS}_FSCACHE[1] - v9fs_init_rreq() should take a ref on the p9_fid and the cleanup should drop it [from Dominique Martinet]. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-and-tested-by: Dominique Martinet <asmadeus@codewreck.org> cc: v9fs-developer@lists.sourceforge.net cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/YUm+xucHxED+1MJp@codewreck.org/ [1] Link: https://lore.kernel.org/r/163162772646.438332.16323773205855053535.stgit@warthog.procyon.org.uk/ # rfc Link: https://lore.kernel.org/r/163189109885.2509237.7153668924503399173.stgit@warthog.procyon.org.uk/ # rfc v2 Link: https://lore.kernel.org/r/163363943896.1980952.1226527304649419689.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/163551662876.1877519.14706391695553204156.stgit@warthog.procyon.org.uk/ # v4 Link: https://lore.kernel.org/r/163584179557.4023316.11089762304657644342.stgit@warthog.procyon.org.uk # rebase on folio Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
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It is generally unsafe to call put_device() with dpm_list_mtx held,
because the given device's release routine may carry out an action
depending on that lock which then may deadlock, so modify the
system-wide suspend and resume of devices to always drop dpm_list_mtx
before calling put_device() (and adjust white space somewhat while
at it).
For instance, this prevents the following splat from showing up in
the kernel log after a system resume in certain configurations:
[ 3290.969514] ======================================================
[ 3290.969517] WARNING: possible circular locking dependency detected
[ 3290.969519] 5.15.0+ #2420 Tainted: G S
[ 3290.969523] ------------------------------------------------------
[ 3290.969525] systemd-sleep/4553 is trying to acquire lock:
[ 3290.969529] ffff888117ab1138 ((wq_completion)hci0#2){+.+.}-{0:0}, at: flush_workqueue+0x87/0x4a0
[ 3290.969554]
but task is already holding lock:
[ 3290.969556] ffffffff8280fca8 (dpm_list_mtx){+.+.}-{3:3}, at: dpm_resume+0x12e/0x3e0
[ 3290.969571]
which lock already depends on the new lock.
[ 3290.969573]
the existing dependency chain (in reverse order) is:
[ 3290.969575]
-> #3 (dpm_list_mtx){+.+.}-{3:3}:
[ 3290.969583] __mutex_lock+0x9d/0xa30
[ 3290.969591] device_pm_add+0x2e/0xe0
[ 3290.969597] device_add+0x4d5/0x8f0
[ 3290.969605] hci_conn_add_sysfs+0x43/0xb0 [bluetooth]
[ 3290.969689] hci_conn_complete_evt.isra.71+0x124/0x750 [bluetooth]
[ 3290.969747] hci_event_packet+0xd6c/0x28a0 [bluetooth]
[ 3290.969798] hci_rx_work+0x213/0x640 [bluetooth]
[ 3290.969842] process_one_work+0x2aa/0x650
[ 3290.969851] worker_thread+0x39/0x400
[ 3290.969859] kthread+0x142/0x170
[ 3290.969865] ret_from_fork+0x22/0x30
[ 3290.969872]
-> #2 (&hdev->lock){+.+.}-{3:3}:
[ 3290.969881] __mutex_lock+0x9d/0xa30
[ 3290.969887] hci_event_packet+0xba/0x28a0 [bluetooth]
[ 3290.969935] hci_rx_work+0x213/0x640 [bluetooth]
[ 3290.969978] process_one_work+0x2aa/0x650
[ 3290.969985] worker_thread+0x39/0x400
[ 3290.969993] kthread+0x142/0x170
[ 3290.969999] ret_from_fork+0x22/0x30
[ 3290.970004]
-> #1 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}:
[ 3290.970013] process_one_work+0x27d/0x650
[ 3290.970020] worker_thread+0x39/0x400
[ 3290.970028] kthread+0x142/0x170
[ 3290.970033] ret_from_fork+0x22/0x30
[ 3290.970038]
-> #0 ((wq_completion)hci0#2){+.+.}-{0:0}:
[ 3290.970047] __lock_acquire+0x15cb/0x1b50
[ 3290.970054] lock_acquire+0x26c/0x300
[ 3290.970059] flush_workqueue+0xae/0x4a0
[ 3290.970066] drain_workqueue+0xa1/0x130
[ 3290.970073] destroy_workqueue+0x34/0x1f0
[ 3290.970081] hci_release_dev+0x49/0x180 [bluetooth]
[ 3290.970130] bt_host_release+0x1d/0x30 [bluetooth]
[ 3290.970195] device_release+0x33/0x90
[ 3290.970201] kobject_release+0x63/0x160
[ 3290.970211] dpm_resume+0x164/0x3e0
[ 3290.970215] dpm_resume_end+0xd/0x20
[ 3290.970220] suspend_devices_and_enter+0x1a4/0xba0
[ 3290.970229] pm_suspend+0x26b/0x310
[ 3290.970236] state_store+0x42/0x90
[ 3290.970243] kernfs_fop_write_iter+0x135/0x1b0
[ 3290.970251] new_sync_write+0x125/0x1c0
[ 3290.970257] vfs_write+0x360/0x3c0
[ 3290.970263] ksys_write+0xa7/0xe0
[ 3290.970269] do_syscall_64+0x3a/0x80
[ 3290.970276] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 3290.970284]
other info that might help us debug this:
[ 3290.970285] Chain exists of:
(wq_completion)hci0#2 --> &hdev->lock --> dpm_list_mtx
[ 3290.970297] Possible unsafe locking scenario:
[ 3290.970299] CPU0 CPU1
[ 3290.970300] ---- ----
[ 3290.970302] lock(dpm_list_mtx);
[ 3290.970306] lock(&hdev->lock);
[ 3290.970310] lock(dpm_list_mtx);
[ 3290.970314] lock((wq_completion)hci0#2);
[ 3290.970319]
*** DEADLOCK ***
[ 3290.970321] 7 locks held by systemd-sleep/4553:
[ 3290.970325] #0: ffff888103bcd448 (sb_writers#4){.+.+}-{0:0}, at: ksys_write+0xa7/0xe0
[ 3290.970341] #1: ffff888115a14488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x103/0x1b0
[ 3290.970355] #2: ffff888100f719e0 (kn->active#233){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x10c/0x1b0
[ 3290.970369] #3: ffffffff82661048 (autosleep_lock){+.+.}-{3:3}, at: state_store+0x12/0x90
[ 3290.970384] #4: ffffffff82658ac8 (system_transition_mutex){+.+.}-{3:3}, at: pm_suspend+0x9f/0x310
[ 3290.970399] #5: ffffffff827f2a48 (acpi_scan_lock){+.+.}-{3:3}, at: acpi_suspend_begin+0x4c/0x80
[ 3290.970416] #6: ffffffff8280fca8 (dpm_list_mtx){+.+.}-{3:3}, at: dpm_resume+0x12e/0x3e0
[ 3290.970428]
stack backtrace:
[ 3290.970431] CPU: 3 PID: 4553 Comm: systemd-sleep Tainted: G S 5.15.0+ #2420
[ 3290.970438] Hardware name: Dell Inc. XPS 13 9380/0RYJWW, BIOS 1.5.0 06/03/2019
[ 3290.970441] Call Trace:
[ 3290.970446] dump_stack_lvl+0x44/0x57
[ 3290.970454] check_noncircular+0x105/0x120
[ 3290.970468] ? __lock_acquire+0x15cb/0x1b50
[ 3290.970474] __lock_acquire+0x15cb/0x1b50
[ 3290.970487] lock_acquire+0x26c/0x300
[ 3290.970493] ? flush_workqueue+0x87/0x4a0
[ 3290.970503] ? __raw_spin_lock_init+0x3b/0x60
[ 3290.970510] ? lockdep_init_map_type+0x58/0x240
[ 3290.970519] flush_workqueue+0xae/0x4a0
[ 3290.970526] ? flush_workqueue+0x87/0x4a0
[ 3290.970544] ? drain_workqueue+0xa1/0x130
[ 3290.970552] drain_workqueue+0xa1/0x130
[ 3290.970561] destroy_workqueue+0x34/0x1f0
[ 3290.970572] hci_release_dev+0x49/0x180 [bluetooth]
[ 3290.970624] bt_host_release+0x1d/0x30 [bluetooth]
[ 3290.970687] device_release+0x33/0x90
[ 3290.970695] kobject_release+0x63/0x160
[ 3290.970705] dpm_resume+0x164/0x3e0
[ 3290.970710] ? dpm_resume_early+0x251/0x3b0
[ 3290.970718] dpm_resume_end+0xd/0x20
[ 3290.970723] suspend_devices_and_enter+0x1a4/0xba0
[ 3290.970737] pm_suspend+0x26b/0x310
[ 3290.970746] state_store+0x42/0x90
[ 3290.970755] kernfs_fop_write_iter+0x135/0x1b0
[ 3290.970764] new_sync_write+0x125/0x1c0
[ 3290.970777] vfs_write+0x360/0x3c0
[ 3290.970785] ksys_write+0xa7/0xe0
[ 3290.970794] do_syscall_64+0x3a/0x80
[ 3290.970803] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 3290.970811] RIP: 0033:0x7f41b1328164
[ 3290.970819] Code: 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 80 00 00 00 00 8b 05 4a d2 2c 00 48 63 ff 85 c0 75 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 f3 c3 66 90 55 53 48 89 d5 48 89 f3 48 83
[ 3290.970824] RSP: 002b:00007ffe6ae21b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[ 3290.970831] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f41b1328164
[ 3290.970836] RDX: 0000000000000004 RSI: 000055965e651070 RDI: 0000000000000004
[ 3290.970839] RBP: 000055965e651070 R08: 000055965e64f390 R09: 00007f41b1e3d1c0
[ 3290.970843] R10: 000000000000000a R11: 0000000000000246 R12: 0000000000000004
[ 3290.970846] R13: 0000000000000001 R14: 000055965e64f2b0 R15: 0000000000000004
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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After removing /dev/kmem, sanitizing /proc/kcore and handling /dev/mem, this series tackles the last sane way how a VM could accidentially access logically unplugged memory managed by a virtio-mem device: /proc/vmcore When dumping memory via "makedumpfile", PG_offline pages, used by virtio-mem to flag logically unplugged memory, are already properly excluded; however, especially when accessing/copying /proc/vmcore "the usual way", we can still end up reading logically unplugged memory part of a virtio-mem device. Patch #1-#3 are cleanups. Patch #4 extends the existing oldmem_pfn_is_ram mechanism. Patch #5-#7 are virtio-mem refactorings for patch #8, which implements the virtio-mem logic to query the state of device blocks. Patch #8: "Although virtio-mem currently supports reading unplugged memory in the hypervisor, this will change in the future, indicated to the device via a new feature flag. We similarly sanitized /proc/kcore access recently. [...] Distributions that support virtio-mem+kdump have to make sure that the virtio_mem module will be part of the kdump kernel or the kdump initrd; dracut was recently [2] extended to include virtio-mem in the generated initrd. As long as no special kdump kernels are used, this will automatically make sure that virtio-mem will be around in the kdump initrd and sanitize /proc/vmcore access -- with dracut" This is the last remaining bit to support VIRTIO_MEM_F_UNPLUGGED_INACCESSIBLE [3] in the Linux implementation of virtio-mem. Note: this is best-effort. We'll never be able to control what runs inside the second kernel, really, but we also don't have to care: we only care about sane setups where we don't want our VM getting zapped once we touch the wrong memory location while dumping. While we usually expect sane setups to use "makedumfile", nothing really speaks against just copying /proc/vmcore, especially in environments where HWpoisioning isn't typically expected. Also, we really don't want to put all our trust completely on the memmap, so sanitizing also makes sense when just using "makedumpfile". [1] https://lkml.kernel.org/r/20210526093041.8800-1-david@redhat.com [2] dracutdevs/dracut#1157 [3] https://lists.oasis-open.org/archives/virtio-comment/202109/msg00021.html This patch (of 9): The callback is only used for the vmcore nowadays. Link: https://lkml.kernel.org/r/20211005121430.30136-1-david@redhat.com Link: https://lkml.kernel.org/r/20211005121430.30136-2-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Boris Ostrovsky <boris.ostrvsky@oracle.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Juergen Gross <jgross@suse.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Dave Young <dyoung@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Mike Rapoport <rppt@kernel.org> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Add a convenience function, folio_inode() that will get the host inode from a folio's mapping. Changes: ver #3: - Fix mistake in function description[2]. ver #2: - Fix contradiction between doc and implementation by disallowing use with swap caches[1]. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Tested-by: Jeff Layton <jlayton@kernel.org> Tested-by: Dominique Martinet <asmadeus@codewreck.org> Tested-by: kafs-testing@auristor.com Link: https://lore.kernel.org/r/YST8OcVNy02Rivbm@casper.infradead.org/ [1] Link: https://lore.kernel.org/r/YYKLkBwQdtn4ja+i@casper.infradead.org/ [2] Link: https://lore.kernel.org/r/162880453171.3369675.3704943108660112470.stgit@warthog.procyon.org.uk/ # rfc Link: https://lore.kernel.org/r/162981151155.1901565.7010079316994382707.stgit@warthog.procyon.org.uk/ Link: https://lore.kernel.org/r/163005744370.2472992.18324470937328925723.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/163584184628.4023316.9386282630968981869.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/163649325519.309189.15072332908703129455.stgit@warthog.procyon.org.uk/ # v4 Link: https://lore.kernel.org/r/163657850401.834781.1031963517399283294.stgit@warthog.procyon.org.uk/ # v5
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…ate_pagetables' [ Upstream commit fddc450 ] This commit addresses a circular locking dependency in the svm_range_cpu_invalidate_pagetables function. The function previously held a lock while determining whether to perform an unmap or eviction operation, which could lead to deadlocks. Fixes the below: [ 223.418794] ====================================================== [ 223.418820] WARNING: possible circular locking dependency detected [ 223.418845] 6.12.0-amdstaging-drm-next-lol-050225 torvalds#14 Tainted: G U OE [ 223.418869] ------------------------------------------------------ [ 223.418889] kfdtest/3939 is trying to acquire lock: [ 223.418906] ffff8957552eae38 (&dqm->lock_hidden){+.+.}-{3:3}, at: evict_process_queues_cpsch+0x43/0x210 [amdgpu] [ 223.419302] but task is already holding lock: [ 223.419303] ffff8957556b83b0 (&prange->lock){+.+.}-{3:3}, at: svm_range_cpu_invalidate_pagetables+0x9d/0x850 [amdgpu] [ 223.419447] Console: switching to colour dummy device 80x25 [ 223.419477] [IGT] amd_basic: executing [ 223.419599] which lock already depends on the new lock. [ 223.419611] the existing dependency chain (in reverse order) is: [ 223.419621] -> #2 (&prange->lock){+.+.}-{3:3}: [ 223.419636] __mutex_lock+0x85/0xe20 [ 223.419647] mutex_lock_nested+0x1b/0x30 [ 223.419656] svm_range_validate_and_map+0x2f1/0x15b0 [amdgpu] [ 223.419954] svm_range_set_attr+0xe8c/0x1710 [amdgpu] [ 223.420236] svm_ioctl+0x46/0x50 [amdgpu] [ 223.420503] kfd_ioctl_svm+0x50/0x90 [amdgpu] [ 223.420763] kfd_ioctl+0x409/0x6d0 [amdgpu] [ 223.421024] __x64_sys_ioctl+0x95/0xd0 [ 223.421036] x64_sys_call+0x1205/0x20d0 [ 223.421047] do_syscall_64+0x87/0x140 [ 223.421056] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 223.421068] -> #1 (reservation_ww_class_mutex){+.+.}-{3:3}: [ 223.421084] __ww_mutex_lock.constprop.0+0xab/0x1560 [ 223.421095] ww_mutex_lock+0x2b/0x90 [ 223.421103] amdgpu_amdkfd_alloc_gtt_mem+0xcc/0x2b0 [amdgpu] [ 223.421361] add_queue_mes+0x3bc/0x440 [amdgpu] [ 223.421623] unhalt_cpsch+0x1ae/0x240 [amdgpu] [ 223.421888] kgd2kfd_start_sched+0x5e/0xd0 [amdgpu] [ 223.422148] amdgpu_amdkfd_start_sched+0x3d/0x50 [amdgpu] [ 223.422414] amdgpu_gfx_enforce_isolation_handler+0x132/0x270 [amdgpu] [ 223.422662] process_one_work+0x21e/0x680 [ 223.422673] worker_thread+0x190/0x330 [ 223.422682] kthread+0xe7/0x120 [ 223.422690] ret_from_fork+0x3c/0x60 [ 223.422699] ret_from_fork_asm+0x1a/0x30 [ 223.422708] -> #0 (&dqm->lock_hidden){+.+.}-{3:3}: [ 223.422723] __lock_acquire+0x16f4/0x2810 [ 223.422734] lock_acquire+0xd1/0x300 [ 223.422742] __mutex_lock+0x85/0xe20 [ 223.422751] mutex_lock_nested+0x1b/0x30 [ 223.422760] evict_process_queues_cpsch+0x43/0x210 [amdgpu] [ 223.423025] kfd_process_evict_queues+0x8a/0x1d0 [amdgpu] [ 223.423285] kgd2kfd_quiesce_mm+0x43/0x90 [amdgpu] [ 223.423540] svm_range_cpu_invalidate_pagetables+0x4a7/0x850 [amdgpu] [ 223.423807] __mmu_notifier_invalidate_range_start+0x1f5/0x250 [ 223.423819] copy_page_range+0x1e94/0x1ea0 [ 223.423829] copy_process+0x172f/0x2ad0 [ 223.423839] kernel_clone+0x9c/0x3f0 [ 223.423847] __do_sys_clone+0x66/0x90 [ 223.423856] __x64_sys_clone+0x25/0x30 [ 223.423864] x64_sys_call+0x1d7c/0x20d0 [ 223.423872] do_syscall_64+0x87/0x140 [ 223.423880] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 223.423891] other info that might help us debug this: [ 223.423903] Chain exists of: &dqm->lock_hidden --> reservation_ww_class_mutex --> &prange->lock [ 223.423926] Possible unsafe locking scenario: [ 223.423935] CPU0 CPU1 [ 223.423942] ---- ---- [ 223.423949] lock(&prange->lock); [ 223.423958] lock(reservation_ww_class_mutex); [ 223.423970] lock(&prange->lock); [ 223.423981] lock(&dqm->lock_hidden); [ 223.423990] *** DEADLOCK *** [ 223.423999] 5 locks held by kfdtest/3939: [ 223.424006] #0: ffffffffb82b4fc0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_process+0x1387/0x2ad0 [ 223.424026] #1: ffff89575eda81b0 (&mm->mmap_lock){++++}-{3:3}, at: copy_process+0x13a8/0x2ad0 [ 223.424046] #2: ffff89575edaf3b0 (&mm->mmap_lock/1){+.+.}-{3:3}, at: copy_process+0x13e4/0x2ad0 [ 223.424066] #3: ffffffffb82e76e0 (mmu_notifier_invalidate_range_start){+.+.}-{0:0}, at: copy_page_range+0x1cea/0x1ea0 [ 223.424088] #4: ffff8957556b83b0 (&prange->lock){+.+.}-{3:3}, at: svm_range_cpu_invalidate_pagetables+0x9d/0x850 [amdgpu] [ 223.424365] stack backtrace: [ 223.424374] CPU: 0 UID: 0 PID: 3939 Comm: kfdtest Tainted: G U OE 6.12.0-amdstaging-drm-next-lol-050225 torvalds#14 [ 223.424392] Tainted: [U]=USER, [O]=OOT_MODULE, [E]=UNSIGNED_MODULE [ 223.424401] Hardware name: Gigabyte Technology Co., Ltd. X570 AORUS PRO WIFI/X570 AORUS PRO WIFI, BIOS F36a 02/16/2022 [ 223.424416] Call Trace: [ 223.424423] <TASK> [ 223.424430] dump_stack_lvl+0x9b/0xf0 [ 223.424441] dump_stack+0x10/0x20 [ 223.424449] print_circular_bug+0x275/0x350 [ 223.424460] check_noncircular+0x157/0x170 [ 223.424469] ? __bfs+0xfd/0x2c0 [ 223.424481] __lock_acquire+0x16f4/0x2810 [ 223.424490] ? srso_return_thunk+0x5/0x5f [ 223.424505] lock_acquire+0xd1/0x300 [ 223.424514] ? evict_process_queues_cpsch+0x43/0x210 [amdgpu] [ 223.424783] __mutex_lock+0x85/0xe20 [ 223.424792] ? evict_process_queues_cpsch+0x43/0x210 [amdgpu] [ 223.425058] ? srso_return_thunk+0x5/0x5f [ 223.425067] ? mark_held_locks+0x54/0x90 [ 223.425076] ? evict_process_queues_cpsch+0x43/0x210 [amdgpu] [ 223.425339] ? srso_return_thunk+0x5/0x5f [ 223.425350] mutex_lock_nested+0x1b/0x30 [ 223.425358] ? mutex_lock_nested+0x1b/0x30 [ 223.425367] evict_process_queues_cpsch+0x43/0x210 [amdgpu] [ 223.425631] kfd_process_evict_queues+0x8a/0x1d0 [amdgpu] [ 223.425893] kgd2kfd_quiesce_mm+0x43/0x90 [amdgpu] [ 223.426156] svm_range_cpu_invalidate_pagetables+0x4a7/0x850 [amdgpu] [ 223.426423] ? srso_return_thunk+0x5/0x5f [ 223.426436] __mmu_notifier_invalidate_range_start+0x1f5/0x250 [ 223.426450] copy_page_range+0x1e94/0x1ea0 [ 223.426461] ? srso_return_thunk+0x5/0x5f [ 223.426474] ? srso_return_thunk+0x5/0x5f [ 223.426484] ? lock_acquire+0xd1/0x300 [ 223.426494] ? copy_process+0x1718/0x2ad0 [ 223.426502] ? srso_return_thunk+0x5/0x5f [ 223.426510] ? sched_clock_noinstr+0x9/0x10 [ 223.426519] ? local_clock_noinstr+0xe/0xc0 [ 223.426528] ? copy_process+0x1718/0x2ad0 [ 223.426537] ? srso_return_thunk+0x5/0x5f [ 223.426550] copy_process+0x172f/0x2ad0 [ 223.426569] kernel_clone+0x9c/0x3f0 [ 223.426577] ? __schedule+0x4c9/0x1b00 [ 223.426586] ? srso_return_thunk+0x5/0x5f [ 223.426594] ? sched_clock_noinstr+0x9/0x10 [ 223.426602] ? srso_return_thunk+0x5/0x5f [ 223.426610] ? local_clock_noinstr+0xe/0xc0 [ 223.426619] ? schedule+0x107/0x1a0 [ 223.426629] __do_sys_clone+0x66/0x90 [ 223.426643] __x64_sys_clone+0x25/0x30 [ 223.426652] x64_sys_call+0x1d7c/0x20d0 [ 223.426661] do_syscall_64+0x87/0x140 [ 223.426671] ? srso_return_thunk+0x5/0x5f [ 223.426679] ? common_nsleep+0x44/0x50 [ 223.426690] ? srso_return_thunk+0x5/0x5f [ 223.426698] ? trace_hardirqs_off+0x52/0xd0 [ 223.426709] ? srso_return_thunk+0x5/0x5f [ 223.426717] ? syscall_exit_to_user_mode+0xcc/0x200 [ 223.426727] ? srso_return_thunk+0x5/0x5f [ 223.426736] ? do_syscall_64+0x93/0x140 [ 223.426748] ? srso_return_thunk+0x5/0x5f [ 223.426756] ? up_write+0x1c/0x1e0 [ 223.426765] ? srso_return_thunk+0x5/0x5f [ 223.426775] ? srso_return_thunk+0x5/0x5f [ 223.426783] ? trace_hardirqs_off+0x52/0xd0 [ 223.426792] ? srso_return_thunk+0x5/0x5f [ 223.426800] ? syscall_exit_to_user_mode+0xcc/0x200 [ 223.426810] ? srso_return_thunk+0x5/0x5f [ 223.426818] ? do_syscall_64+0x93/0x140 [ 223.426826] ? syscall_exit_to_user_mode+0xcc/0x200 [ 223.426836] ? srso_return_thunk+0x5/0x5f [ 223.426844] ? do_syscall_64+0x93/0x140 [ 223.426853] ? srso_return_thunk+0x5/0x5f [ 223.426861] ? irqentry_exit+0x6b/0x90 [ 223.426869] ? srso_return_thunk+0x5/0x5f [ 223.426877] ? exc_page_fault+0xa7/0x2c0 [ 223.426888] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 223.426898] RIP: 0033:0x7f46758eab57 [ 223.426906] Code: ba 04 00 f3 0f 1e fa 64 48 8b 04 25 10 00 00 00 45 31 c0 31 d2 31 f6 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 41 41 89 c0 85 c0 75 2c 64 48 8b 04 25 10 00 [ 223.426930] RSP: 002b:00007fff5c3e5188 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 [ 223.426943] RAX: ffffffffffffffda RBX: 00007f4675f8c040 RCX: 00007f46758eab57 [ 223.426954] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 [ 223.426965] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 223.426975] R10: 00007f4675e81a50 R11: 0000000000000246 R12: 0000000000000001 [ 223.426986] R13: 00007fff5c3e5470 R14: 00007fff5c3e53e0 R15: 00007fff5c3e5410 [ 223.427004] </TASK> v2: To resolve this issue, the allocation of the process context buffer (`proc_ctx_bo`) has been moved from the `add_queue_mes` function to the `pqm_create_queue` function. This change ensures that the buffer is allocated only when the first queue for a process is created and only if the Micro Engine Scheduler (MES) is enabled. (Felix) v3: Fix typo s/Memory Execution Scheduler (MES)/Micro Engine Scheduler in commit message. (Lijo) Fixes: 438b39a ("drm/amdkfd: pause autosuspend when creating pdd") Cc: Jesse Zhang <jesse.zhang@amd.com> Cc: Yunxiang Li <Yunxiang.Li@amd.com> Cc: Philip Yang <Philip.Yang@amd.com> Cc: Alex Sierra <alex.sierra@amd.com> Cc: Felix Kuehling <Felix.Kuehling@amd.com> Cc: Christian König <christian.koenig@amd.com> Cc: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com> Reviewed-by: Felix Kuehling <felix.kuehling@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 888751e ] perf test 11 hwmon fails on s390 with this error # ./perf test -Fv 11 --- start --- ---- end ---- 11.1: Basic parsing test : Ok --- start --- Testing 'temp_test_hwmon_event1' Using CPUID IBM,3931,704,A01,3.7,002f temp_test_hwmon_event1 -> hwmon_a_test_hwmon_pmu/temp_test_hwmon_event1/ FAILED tests/hwmon_pmu.c:189 Unexpected config for 'temp_test_hwmon_event1', 292470092988416 != 655361 ---- end ---- 11.2: Parsing without PMU name : FAILED! --- start --- Testing 'hwmon_a_test_hwmon_pmu/temp_test_hwmon_event1/' FAILED tests/hwmon_pmu.c:189 Unexpected config for 'hwmon_a_test_hwmon_pmu/temp_test_hwmon_event1/', 292470092988416 != 655361 ---- end ---- 11.3: Parsing with PMU name : FAILED! # The root cause is in member test_event::config which is initialized to 0xA0001 or 655361. During event parsing a long list event parsing functions are called and end up with this gdb call stack: #0 hwmon_pmu__config_term (hwm=0x168dfd0, attr=0x3ffffff5ee8, term=0x168db60, err=0x3ffffff81c8) at util/hwmon_pmu.c:623 #1 hwmon_pmu__config_terms (pmu=0x168dfd0, attr=0x3ffffff5ee8, terms=0x3ffffff5ea8, err=0x3ffffff81c8) at util/hwmon_pmu.c:662 #2 0x00000000012f870c in perf_pmu__config_terms (pmu=0x168dfd0, attr=0x3ffffff5ee8, terms=0x3ffffff5ea8, zero=false, apply_hardcoded=false, err=0x3ffffff81c8) at util/pmu.c:1519 #3 0x00000000012f88a4 in perf_pmu__config (pmu=0x168dfd0, attr=0x3ffffff5ee8, head_terms=0x3ffffff5ea8, apply_hardcoded=false, err=0x3ffffff81c8) at util/pmu.c:1545 #4 0x00000000012680c4 in parse_events_add_pmu (parse_state=0x3ffffff7fb8, list=0x168dc00, pmu=0x168dfd0, const_parsed_terms=0x3ffffff6090, auto_merge_stats=true, alternate_hw_config=10) at util/parse-events.c:1508 #5 0x00000000012684c6 in parse_events_multi_pmu_add (parse_state=0x3ffffff7fb8, event_name=0x168ec10 "temp_test_hwmon_event1", hw_config=10, const_parsed_terms=0x0, listp=0x3ffffff6230, loc_=0x3ffffff70e0) at util/parse-events.c:1592 #6 0x00000000012f0e4e in parse_events_parse (_parse_state=0x3ffffff7fb8, scanner=0x16878c0) at util/parse-events.y:293 #7 0x00000000012695a0 in parse_events__scanner (str=0x3ffffff81d8 "temp_test_hwmon_event1", input=0x0, parse_state=0x3ffffff7fb8) at util/parse-events.c:1867 #8 0x000000000126a1e8 in __parse_events (evlist=0x168b580, str=0x3ffffff81d8 "temp_test_hwmon_event1", pmu_filter=0x0, err=0x3ffffff81c8, fake_pmu=false, warn_if_reordered=true, fake_tp=false) at util/parse-events.c:2136 #9 0x00000000011e36aa in parse_events (evlist=0x168b580, str=0x3ffffff81d8 "temp_test_hwmon_event1", err=0x3ffffff81c8) at /root/linux/tools/perf/util/parse-events.h:41 torvalds#10 0x00000000011e3e64 in do_test (i=0, with_pmu=false, with_alias=false) at tests/hwmon_pmu.c:164 torvalds#11 0x00000000011e422c in test__hwmon_pmu (with_pmu=false) at tests/hwmon_pmu.c:219 torvalds#12 0x00000000011e431c in test__hwmon_pmu_without_pmu (test=0x1610368 <suite.hwmon_pmu>, subtest=1) at tests/hwmon_pmu.c:23 where the attr::config is set to value 292470092988416 or 0x10a0000000000 in line 625 of file ./util/hwmon_pmu.c: attr->config = key.type_and_num; However member key::type_and_num is defined as union and bit field: union hwmon_pmu_event_key { long type_and_num; struct { int num :16; enum hwmon_type type :8; }; }; s390 is big endian and Intel is little endian architecture. The events for the hwmon dummy pmu have num = 1 or num = 2 and type is set to HWMON_TYPE_TEMP (which is 10). On s390 this assignes member key::type_and_num the value of 0x10a0000000000 (which is 292470092988416) as shown in above trace output. Fix this and export the structure/union hwmon_pmu_event_key so the test shares the same implementation as the event parsing functions for union and bit fields. This should avoid endianess issues on all platforms. Output after: # ./perf test -F 11 11.1: Basic parsing test : Ok 11.2: Parsing without PMU name : Ok 11.3: Parsing with PMU name : Ok # Fixes: 531ee0f ("perf test: Add hwmon "PMU" test") Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Reviewed-by: Ian Rogers <irogers@google.com> Link: https://lore.kernel.org/r/20250131112400.568975-1-tmricht@linux.ibm.com Signed-off-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit f1ab283 ] Patch series "Fix calculations in trace_balance_dirty_pages() for cgwb", v2. In my experiment, I found that the output of trace_balance_dirty_pages() in the cgroup writeback scenario was strange because trace_balance_dirty_pages() always uses global_wb_domain.dirty_limit for related calculations instead of the dirty_limit of the corresponding memcg's wb_domain. The basic idea of the fix is to store the hard dirty limit value computed in wb_position_ratio() into struct dirty_throttle_control and use it for calculations in trace_balance_dirty_pages(). This patch (of 3): Currently, trace_balance_dirty_pages() already has 12 parameters. In the patch #3, I initially attempted to introduce an additional parameter. However, in include/linux/trace_events.h, bpf_trace_run12() only supports up to 12 parameters and bpf_trace_run13() does not exist. To reduce the number of parameters in trace_balance_dirty_pages(), we can make it accept a pointer to struct dirty_throttle_control as a parameter. To achieve this, we need to move the definition of struct dirty_throttle_control from mm/page-writeback.c to include/linux/writeback.h. Link: https://lkml.kernel.org/r/20250304110318.159567-1-yizhou.tang@shopee.com Link: https://lkml.kernel.org/r/20250304110318.159567-2-yizhou.tang@shopee.com Signed-off-by: Tang Yizhou <yizhou.tang@shopee.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Christian Brauner <brauner@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Jan Kara <jack@suse.cz> Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Cc: Matthew Wilcow (Oracle) <willy@infradead.org> Cc: Tang Yizhou <yizhou.tang@shopee.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Stable-dep-of: 6cc4c3a ("writeback: fix calculations in trace_balance_dirty_pages() for cgwb") Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 053f3ff ] v2: - Created a single error handling unlock and exit in veth_pool_store - Greatly expanded commit message with previous explanatory-only text Summary: Use rtnl_mutex to synchronize veth_pool_store with itself, ibmveth_close and ibmveth_open, preventing multiple calls in a row to napi_disable. Background: Two (or more) threads could call veth_pool_store through writing to /sys/devices/vio/30000002/pool*/*. You can do this easily with a little shell script. This causes a hang. I configured LOCKDEP, compiled ibmveth.c with DEBUG, and built a new kernel. I ran this test again and saw: Setting pool0/active to 0 Setting pool1/active to 1 [ 73.911067][ T4365] ibmveth 30000002 eth0: close starting Setting pool1/active to 1 Setting pool1/active to 0 [ 73.911367][ T4366] ibmveth 30000002 eth0: close starting [ 73.916056][ T4365] ibmveth 30000002 eth0: close complete [ 73.916064][ T4365] ibmveth 30000002 eth0: open starting [ 110.808564][ T712] systemd-journald[712]: Sent WATCHDOG=1 notification. [ 230.808495][ T712] systemd-journald[712]: Sent WATCHDOG=1 notification. [ 243.683786][ T123] INFO: task stress.sh:4365 blocked for more than 122 seconds. [ 243.683827][ T123] Not tainted 6.14.0-01103-g2df0c02dab82-dirty #8 [ 243.683833][ T123] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 243.683838][ T123] task:stress.sh state:D stack:28096 pid:4365 tgid:4365 ppid:4364 task_flags:0x400040 flags:0x00042000 [ 243.683852][ T123] Call Trace: [ 243.683857][ T123] [c00000000c38f690] [0000000000000001] 0x1 (unreliable) [ 243.683868][ T123] [c00000000c38f840] [c00000000001f908] __switch_to+0x318/0x4e0 [ 243.683878][ T123] [c00000000c38f8a0] [c000000001549a70] __schedule+0x500/0x12a0 [ 243.683888][ T123] [c00000000c38f9a0] [c00000000154a878] schedule+0x68/0x210 [ 243.683896][ T123] [c00000000c38f9d0] [c00000000154ac80] schedule_preempt_disabled+0x30/0x50 [ 243.683904][ T123] [c00000000c38fa00] [c00000000154dbb0] __mutex_lock+0x730/0x10f0 [ 243.683913][ T123] [c00000000c38fb10] [c000000001154d40] napi_enable+0x30/0x60 [ 243.683921][ T123] [c00000000c38fb40] [c000000000f4ae94] ibmveth_open+0x68/0x5dc [ 243.683928][ T123] [c00000000c38fbe0] [c000000000f4aa20] veth_pool_store+0x220/0x270 [ 243.683936][ T123] [c00000000c38fc70] [c000000000826278] sysfs_kf_write+0x68/0xb0 [ 243.683944][ T123] [c00000000c38fcb0] [c0000000008240b8] kernfs_fop_write_iter+0x198/0x2d0 [ 243.683951][ T123] [c00000000c38fd00] [c00000000071b9ac] vfs_write+0x34c/0x650 [ 243.683958][ T123] [c00000000c38fdc0] [c00000000071bea8] ksys_write+0x88/0x150 [ 243.683966][ T123] [c00000000c38fe10] [c0000000000317f4] system_call_exception+0x124/0x340 [ 243.683973][ T123] [c00000000c38fe50] [c00000000000d05c] system_call_vectored_common+0x15c/0x2ec ... [ 243.684087][ T123] Showing all locks held in the system: [ 243.684095][ T123] 1 lock held by khungtaskd/123: [ 243.684099][ T123] #0: c00000000278e370 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x50/0x248 [ 243.684114][ T123] 4 locks held by stress.sh/4365: [ 243.684119][ T123] #0: c00000003a4cd3f8 (sb_writers#3){.+.+}-{0:0}, at: ksys_write+0x88/0x150 [ 243.684132][ T123] #1: c000000041aea888 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x154/0x2d0 [ 243.684143][ T123] #2: c0000000366fb9a8 (kn->active#64){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x160/0x2d0 [ 243.684155][ T123] #3: c000000035ff4cb8 (&dev->lock){+.+.}-{3:3}, at: napi_enable+0x30/0x60 [ 243.684166][ T123] 5 locks held by stress.sh/4366: [ 243.684170][ T123] #0: c00000003a4cd3f8 (sb_writers#3){.+.+}-{0:0}, at: ksys_write+0x88/0x150 [ 243.684183][ T123] #1: c00000000aee2288 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x154/0x2d0 [ 243.684194][ T123] #2: c0000000366f4ba8 (kn->active#64){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x160/0x2d0 [ 243.684205][ T123] #3: c000000035ff4cb8 (&dev->lock){+.+.}-{3:3}, at: napi_disable+0x30/0x60 [ 243.684216][ T123] #4: c0000003ff9bbf18 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x138/0x12a0 From the ibmveth debug, two threads are calling veth_pool_store, which calls ibmveth_close and ibmveth_open. Here's the sequence: T4365 T4366 ----------------- ----------------- --------- veth_pool_store veth_pool_store ibmveth_close ibmveth_close napi_disable napi_disable ibmveth_open napi_enable <- HANG ibmveth_close calls napi_disable at the top and ibmveth_open calls napi_enable at the top. https://docs.kernel.org/networking/napi.html]] says The control APIs are not idempotent. Control API calls are safe against concurrent use of datapath APIs but an incorrect sequence of control API calls may result in crashes, deadlocks, or race conditions. For example, calling napi_disable() multiple times in a row will deadlock. In the normal open and close paths, rtnl_mutex is acquired to prevent other callers. This is missing from veth_pool_store. Use rtnl_mutex in veth_pool_store fixes these hangs. Signed-off-by: Dave Marquardt <davemarq@linux.ibm.com> Fixes: 860f242 ("[PATCH] ibmveth change buffer pools dynamically") Reviewed-by: Nick Child <nnac123@linux.ibm.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20250402154403.386744-1-davemarq@linux.ibm.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 52323ed ] syzbot reported a deadlock in lock_system_sleep() (see below). The write operation to "/sys/module/hibernate/parameters/compressor" conflicts with the registration of ieee80211 device, resulting in a deadlock when attempting to acquire system_transition_mutex under param_lock. To avoid this deadlock, change hibernate_compressor_param_set() to use mutex_trylock() for attempting to acquire system_transition_mutex and return -EBUSY when it fails. Task flags need not be saved or adjusted before calling mutex_trylock(&system_transition_mutex) because the caller is not going to end up waiting for this mutex and if it runs concurrently with system suspend in progress, it will be frozen properly when it returns to user space. syzbot report: syz-executor895/5833 is trying to acquire lock: ffffffff8e0828c8 (system_transition_mutex){+.+.}-{4:4}, at: lock_system_sleep+0x87/0xa0 kernel/power/main.c:56 but task is already holding lock: ffffffff8e07dc68 (param_lock){+.+.}-{4:4}, at: kernel_param_lock kernel/params.c:607 [inline] ffffffff8e07dc68 (param_lock){+.+.}-{4:4}, at: param_attr_store+0xe6/0x300 kernel/params.c:586 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (param_lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730 ieee80211_rate_control_ops_get net/mac80211/rate.c:220 [inline] rate_control_alloc net/mac80211/rate.c:266 [inline] ieee80211_init_rate_ctrl_alg+0x18d/0x6b0 net/mac80211/rate.c:1015 ieee80211_register_hw+0x20cd/0x4060 net/mac80211/main.c:1531 mac80211_hwsim_new_radio+0x304e/0x54e0 drivers/net/wireless/virtual/mac80211_hwsim.c:5558 init_mac80211_hwsim+0x432/0x8c0 drivers/net/wireless/virtual/mac80211_hwsim.c:6910 do_one_initcall+0x128/0x700 init/main.c:1257 do_initcall_level init/main.c:1319 [inline] do_initcalls init/main.c:1335 [inline] do_basic_setup init/main.c:1354 [inline] kernel_init_freeable+0x5c7/0x900 init/main.c:1568 kernel_init+0x1c/0x2b0 init/main.c:1457 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #2 (rtnl_mutex){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730 wg_pm_notification drivers/net/wireguard/device.c:80 [inline] wg_pm_notification+0x49/0x180 drivers/net/wireguard/device.c:64 notifier_call_chain+0xb7/0x410 kernel/notifier.c:85 notifier_call_chain_robust kernel/notifier.c:120 [inline] blocking_notifier_call_chain_robust kernel/notifier.c:345 [inline] blocking_notifier_call_chain_robust+0xc9/0x170 kernel/notifier.c:333 pm_notifier_call_chain_robust+0x27/0x60 kernel/power/main.c:102 snapshot_open+0x189/0x2b0 kernel/power/user.c:77 misc_open+0x35a/0x420 drivers/char/misc.c:179 chrdev_open+0x237/0x6a0 fs/char_dev.c:414 do_dentry_open+0x735/0x1c40 fs/open.c:956 vfs_open+0x82/0x3f0 fs/open.c:1086 do_open fs/namei.c:3830 [inline] path_openat+0x1e88/0x2d80 fs/namei.c:3989 do_filp_open+0x20c/0x470 fs/namei.c:4016 do_sys_openat2+0x17a/0x1e0 fs/open.c:1428 do_sys_open fs/open.c:1443 [inline] __do_sys_openat fs/open.c:1459 [inline] __se_sys_openat fs/open.c:1454 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1454 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 ((pm_chain_head).rwsem){++++}-{4:4}: down_read+0x9a/0x330 kernel/locking/rwsem.c:1524 blocking_notifier_call_chain_robust kernel/notifier.c:344 [inline] blocking_notifier_call_chain_robust+0xa9/0x170 kernel/notifier.c:333 pm_notifier_call_chain_robust+0x27/0x60 kernel/power/main.c:102 snapshot_open+0x189/0x2b0 kernel/power/user.c:77 misc_open+0x35a/0x420 drivers/char/misc.c:179 chrdev_open+0x237/0x6a0 fs/char_dev.c:414 do_dentry_open+0x735/0x1c40 fs/open.c:956 vfs_open+0x82/0x3f0 fs/open.c:1086 do_open fs/namei.c:3830 [inline] path_openat+0x1e88/0x2d80 fs/namei.c:3989 do_filp_open+0x20c/0x470 fs/namei.c:4016 do_sys_openat2+0x17a/0x1e0 fs/open.c:1428 do_sys_open fs/open.c:1443 [inline] __do_sys_openat fs/open.c:1459 [inline] __se_sys_openat fs/open.c:1454 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1454 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (system_transition_mutex){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3163 [inline] check_prevs_add kernel/locking/lockdep.c:3282 [inline] validate_chain kernel/locking/lockdep.c:3906 [inline] __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5228 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5851 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730 lock_system_sleep+0x87/0xa0 kernel/power/main.c:56 hibernate_compressor_param_set+0x1c/0x210 kernel/power/hibernate.c:1452 param_attr_store+0x18f/0x300 kernel/params.c:588 module_attr_store+0x55/0x80 kernel/params.c:924 sysfs_kf_write+0x117/0x170 fs/sysfs/file.c:139 kernfs_fop_write_iter+0x33d/0x500 fs/kernfs/file.c:334 new_sync_write fs/read_write.c:586 [inline] vfs_write+0x5ae/0x1150 fs/read_write.c:679 ksys_write+0x12b/0x250 fs/read_write.c:731 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: system_transition_mutex --> rtnl_mutex --> param_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(param_lock); lock(rtnl_mutex); lock(param_lock); lock(system_transition_mutex); *** DEADLOCK *** Reported-by: syzbot+ace60642828c074eb913@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=ace60642828c074eb913 Signed-off-by: Lizhi Xu <lizhi.xu@windriver.com> Link: https://patch.msgid.link/20250224013139.3994500-1-lizhi.xu@windriver.com [ rjw: New subject matching the code changes, changelog edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit b61e69b ] syzbot report a deadlock in diFree. [1] When calling "ioctl$LOOP_SET_STATUS64", the offset value passed in is 4, which does not match the mounted loop device, causing the mapping of the mounted loop device to be invalidated. When creating the directory and creating the inode of iag in diReadSpecial(), read the page of fixed disk inode (AIT) in raw mode in read_metapage(), the metapage data it returns is corrupted, which causes the nlink value of 0 to be assigned to the iag inode when executing copy_from_dinode(), which ultimately causes a deadlock when entering diFree(). To avoid this, first check the nlink value of dinode before setting iag inode. [1] WARNING: possible recursive locking detected 6.12.0-rc7-syzkaller-00212-g4a5df3796467 #0 Not tainted -------------------------------------------- syz-executor301/5309 is trying to acquire lock: ffff888044548920 (&(imap->im_aglock[index])){+.+.}-{3:3}, at: diFree+0x37c/0x2fb0 fs/jfs/jfs_imap.c:889 but task is already holding lock: ffff888044548920 (&(imap->im_aglock[index])){+.+.}-{3:3}, at: diAlloc+0x1b6/0x1630 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&(imap->im_aglock[index])); lock(&(imap->im_aglock[index])); *** DEADLOCK *** May be due to missing lock nesting notation 5 locks held by syz-executor301/5309: #0: ffff8880422a4420 (sb_writers#9){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515 #1: ffff88804755b390 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:850 [inline] #1: ffff88804755b390 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: filename_create+0x260/0x540 fs/namei.c:4026 #2: ffff888044548920 (&(imap->im_aglock[index])){+.+.}-{3:3}, at: diAlloc+0x1b6/0x1630 #3: ffff888044548890 (&imap->im_freelock){+.+.}-{3:3}, at: diNewIAG fs/jfs/jfs_imap.c:2460 [inline] #3: ffff888044548890 (&imap->im_freelock){+.+.}-{3:3}, at: diAllocExt fs/jfs/jfs_imap.c:1905 [inline] #3: ffff888044548890 (&imap->im_freelock){+.+.}-{3:3}, at: diAllocAG+0x4b7/0x1e50 fs/jfs/jfs_imap.c:1669 #4: ffff88804755a618 (&jfs_ip->rdwrlock/1){++++}-{3:3}, at: diNewIAG fs/jfs/jfs_imap.c:2477 [inline] #4: ffff88804755a618 (&jfs_ip->rdwrlock/1){++++}-{3:3}, at: diAllocExt fs/jfs/jfs_imap.c:1905 [inline] #4: ffff88804755a618 (&jfs_ip->rdwrlock/1){++++}-{3:3}, at: diAllocAG+0x869/0x1e50 fs/jfs/jfs_imap.c:1669 stack backtrace: CPU: 0 UID: 0 PID: 5309 Comm: syz-executor301 Not tainted 6.12.0-rc7-syzkaller-00212-g4a5df3796467 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_deadlock_bug+0x483/0x620 kernel/locking/lockdep.c:3037 check_deadlock kernel/locking/lockdep.c:3089 [inline] validate_chain+0x15e2/0x5920 kernel/locking/lockdep.c:3891 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5202 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 diFree+0x37c/0x2fb0 fs/jfs/jfs_imap.c:889 jfs_evict_inode+0x32d/0x440 fs/jfs/inode.c:156 evict+0x4e8/0x9b0 fs/inode.c:725 diFreeSpecial fs/jfs/jfs_imap.c:552 [inline] duplicateIXtree+0x3c6/0x550 fs/jfs/jfs_imap.c:3022 diNewIAG fs/jfs/jfs_imap.c:2597 [inline] diAllocExt fs/jfs/jfs_imap.c:1905 [inline] diAllocAG+0x17dc/0x1e50 fs/jfs/jfs_imap.c:1669 diAlloc+0x1d2/0x1630 fs/jfs/jfs_imap.c:1590 ialloc+0x8f/0x900 fs/jfs/jfs_inode.c:56 jfs_mkdir+0x1c5/0xba0 fs/jfs/namei.c:225 vfs_mkdir+0x2f9/0x4f0 fs/namei.c:4257 do_mkdirat+0x264/0x3a0 fs/namei.c:4280 __do_sys_mkdirat fs/namei.c:4295 [inline] __se_sys_mkdirat fs/namei.c:4293 [inline] __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4293 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Reported-by: syzbot+355da3b3a74881008e8f@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=355da3b3a74881008e8f Signed-off-by: Edward Adam Davis <eadavis@qq.com> Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit 93ae6e6 upstream. We have recently seen report of lockdep circular lock dependency warnings on platforms like Skylake and Kabylake: ====================================================== WARNING: possible circular locking dependency detected 6.14.0-rc6-CI_DRM_16276-gca2c04fe76e8+ #1 Not tainted ------------------------------------------------------ swapper/0/1 is trying to acquire lock: ffffffff8360ee48 (iommu_probe_device_lock){+.+.}-{3:3}, at: iommu_probe_device+0x1d/0x70 but task is already holding lock: ffff888102c7efa8 (&device->physical_node_lock){+.+.}-{3:3}, at: intel_iommu_init+0xe75/0x11f0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #6 (&device->physical_node_lock){+.+.}-{3:3}: __mutex_lock+0xb4/0xe40 mutex_lock_nested+0x1b/0x30 intel_iommu_init+0xe75/0x11f0 pci_iommu_init+0x13/0x70 do_one_initcall+0x62/0x3f0 kernel_init_freeable+0x3da/0x6a0 kernel_init+0x1b/0x200 ret_from_fork+0x44/0x70 ret_from_fork_asm+0x1a/0x30 -> #5 (dmar_global_lock){++++}-{3:3}: down_read+0x43/0x1d0 enable_drhd_fault_handling+0x21/0x110 cpuhp_invoke_callback+0x4c6/0x870 cpuhp_issue_call+0xbf/0x1f0 __cpuhp_setup_state_cpuslocked+0x111/0x320 __cpuhp_setup_state+0xb0/0x220 irq_remap_enable_fault_handling+0x3f/0xa0 apic_intr_mode_init+0x5c/0x110 x86_late_time_init+0x24/0x40 start_kernel+0x895/0xbd0 x86_64_start_reservations+0x18/0x30 x86_64_start_kernel+0xbf/0x110 common_startup_64+0x13e/0x141 -> #4 (cpuhp_state_mutex){+.+.}-{3:3}: __mutex_lock+0xb4/0xe40 mutex_lock_nested+0x1b/0x30 __cpuhp_setup_state_cpuslocked+0x67/0x320 __cpuhp_setup_state+0xb0/0x220 page_alloc_init_cpuhp+0x2d/0x60 mm_core_init+0x18/0x2c0 start_kernel+0x576/0xbd0 x86_64_start_reservations+0x18/0x30 x86_64_start_kernel+0xbf/0x110 common_startup_64+0x13e/0x141 -> #3 (cpu_hotplug_lock){++++}-{0:0}: __cpuhp_state_add_instance+0x4f/0x220 iova_domain_init_rcaches+0x214/0x280 iommu_setup_dma_ops+0x1a4/0x710 iommu_device_register+0x17d/0x260 intel_iommu_init+0xda4/0x11f0 pci_iommu_init+0x13/0x70 do_one_initcall+0x62/0x3f0 kernel_init_freeable+0x3da/0x6a0 kernel_init+0x1b/0x200 ret_from_fork+0x44/0x70 ret_from_fork_asm+0x1a/0x30 -> #2 (&domain->iova_cookie->mutex){+.+.}-{3:3}: __mutex_lock+0xb4/0xe40 mutex_lock_nested+0x1b/0x30 iommu_setup_dma_ops+0x16b/0x710 iommu_device_register+0x17d/0x260 intel_iommu_init+0xda4/0x11f0 pci_iommu_init+0x13/0x70 do_one_initcall+0x62/0x3f0 kernel_init_freeable+0x3da/0x6a0 kernel_init+0x1b/0x200 ret_from_fork+0x44/0x70 ret_from_fork_asm+0x1a/0x30 -> #1 (&group->mutex){+.+.}-{3:3}: __mutex_lock+0xb4/0xe40 mutex_lock_nested+0x1b/0x30 __iommu_probe_device+0x24c/0x4e0 probe_iommu_group+0x2b/0x50 bus_for_each_dev+0x7d/0xe0 iommu_device_register+0xe1/0x260 intel_iommu_init+0xda4/0x11f0 pci_iommu_init+0x13/0x70 do_one_initcall+0x62/0x3f0 kernel_init_freeable+0x3da/0x6a0 kernel_init+0x1b/0x200 ret_from_fork+0x44/0x70 ret_from_fork_asm+0x1a/0x30 -> #0 (iommu_probe_device_lock){+.+.}-{3:3}: __lock_acquire+0x1637/0x2810 lock_acquire+0xc9/0x300 __mutex_lock+0xb4/0xe40 mutex_lock_nested+0x1b/0x30 iommu_probe_device+0x1d/0x70 intel_iommu_init+0xe90/0x11f0 pci_iommu_init+0x13/0x70 do_one_initcall+0x62/0x3f0 kernel_init_freeable+0x3da/0x6a0 kernel_init+0x1b/0x200 ret_from_fork+0x44/0x70 ret_from_fork_asm+0x1a/0x30 other info that might help us debug this: Chain exists of: iommu_probe_device_lock --> dmar_global_lock --> &device->physical_node_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&device->physical_node_lock); lock(dmar_global_lock); lock(&device->physical_node_lock); lock(iommu_probe_device_lock); *** DEADLOCK *** This driver uses a global lock to protect the list of enumerated DMA remapping units. It is necessary due to the driver's support for dynamic addition and removal of remapping units at runtime. Two distinct code paths require iteration over this remapping unit list: - Device registration and probing: the driver iterates the list to register each remapping unit with the upper layer IOMMU framework and subsequently probe the devices managed by that unit. - Global configuration: Upper layer components may also iterate the list to apply configuration changes. The lock acquisition order between these two code paths was reversed. This caused lockdep warnings, indicating a risk of deadlock. Fix this warning by releasing the global lock before invoking upper layer interfaces for device registration. Fixes: b150654 ("iommu/vt-d: Fix suspicious RCU usage") Closes: https://lore.kernel.org/linux-iommu/SJ1PR11MB612953431F94F18C954C4A9CB9D32@SJ1PR11MB6129.namprd11.prod.outlook.com/ Tested-by: Chaitanya Kumar Borah <chaitanya.kumar.borah@intel.com> Cc: stable@vger.kernel.org Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Link: https://lore.kernel.org/r/20250317035714.1041549-1-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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…cesses commit ef01cac upstream. Acquire a lock on kvm->srcu when userspace is getting MP state to handle a rather extreme edge case where "accepting" APIC events, i.e. processing pending INIT or SIPI, can trigger accesses to guest memory. If the vCPU is in L2 with INIT *and* a TRIPLE_FAULT request pending, then getting MP state will trigger a nested VM-Exit by way of ->check_nested_events(), and emuating the nested VM-Exit can access guest memory. The splat was originally hit by syzkaller on a Google-internal kernel, and reproduced on an upstream kernel by hacking the triple_fault_event_test selftest to stuff a pending INIT, store an MSR on VM-Exit (to generate a memory access on VMX), and do vcpu_mp_state_get() to trigger the scenario. ============================= WARNING: suspicious RCU usage 6.14.0-rc3-b112d356288b-vmx/pi_lockdep_false_pos-lock #3 Not tainted ----------------------------- include/linux/kvm_host.h:1058 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by triple_fault_ev/1256: #0: ffff88810df5a330 (&vcpu->mutex){+.+.}-{4:4}, at: kvm_vcpu_ioctl+0x8b/0x9a0 [kvm] stack backtrace: CPU: 11 UID: 1000 PID: 1256 Comm: triple_fault_ev Not tainted 6.14.0-rc3-b112d356288b-vmx #3 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 Call Trace: <TASK> dump_stack_lvl+0x7f/0x90 lockdep_rcu_suspicious+0x144/0x190 kvm_vcpu_gfn_to_memslot+0x156/0x180 [kvm] kvm_vcpu_read_guest+0x3e/0x90 [kvm] read_and_check_msr_entry+0x2e/0x180 [kvm_intel] __nested_vmx_vmexit+0x550/0xde0 [kvm_intel] kvm_check_nested_events+0x1b/0x30 [kvm] kvm_apic_accept_events+0x33/0x100 [kvm] kvm_arch_vcpu_ioctl_get_mpstate+0x30/0x1d0 [kvm] kvm_vcpu_ioctl+0x33e/0x9a0 [kvm] __x64_sys_ioctl+0x8b/0xb0 do_syscall_64+0x6c/0x170 entry_SYSCALL_64_after_hwframe+0x4b/0x53 </TASK> Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com> Message-ID: <20250401150504.829812-1-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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There is a potential deadlock if we do report zones in an IO context, detailed in below lockdep report. When one process do a report zones and another process freezes the block device, the report zones side cannot allocate a tag because the freeze is already started. This can thus result in new block group creation to hang forever, blocking the write path. Thankfully, a new block group should be created on empty zones. So, reporting the zones is not necessary and we can set the write pointer = 0 and load the zone capacity from the block layer using bdev_zone_capacity() helper. ====================================================== WARNING: possible circular locking dependency detected 6.14.0-rc1 torvalds#252 Not tainted ------------------------------------------------------ modprobe/1110 is trying to acquire lock: ffff888100ac83e0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: __flush_work+0x38f/0xb60 but task is already holding lock: ffff8881205b6f20 (&q->q_usage_counter(queue)torvalds#16){++++}-{0:0}, at: sd_remove+0x85/0x130 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&q->q_usage_counter(queue)torvalds#16){++++}-{0:0}: blk_queue_enter+0x3d9/0x500 blk_mq_alloc_request+0x47d/0x8e0 scsi_execute_cmd+0x14f/0xb80 sd_zbc_do_report_zones+0x1c1/0x470 sd_zbc_report_zones+0x362/0xd60 blkdev_report_zones+0x1b1/0x2e0 btrfs_get_dev_zones+0x215/0x7e0 [btrfs] btrfs_load_block_group_zone_info+0x6d2/0x2c10 [btrfs] btrfs_make_block_group+0x36b/0x870 [btrfs] btrfs_create_chunk+0x147d/0x2320 [btrfs] btrfs_chunk_alloc+0x2ce/0xcf0 [btrfs] start_transaction+0xce6/0x1620 [btrfs] btrfs_uuid_scan_kthread+0x4ee/0x5b0 [btrfs] kthread+0x39d/0x750 ret_from_fork+0x30/0x70 ret_from_fork_asm+0x1a/0x30 -> #2 (&fs_info->dev_replace.rwsem){++++}-{4:4}: down_read+0x9b/0x470 btrfs_map_block+0x2ce/0x2ce0 [btrfs] btrfs_submit_chunk+0x2d4/0x16c0 [btrfs] btrfs_submit_bbio+0x16/0x30 [btrfs] btree_write_cache_pages+0xb5a/0xf90 [btrfs] do_writepages+0x17f/0x7b0 __writeback_single_inode+0x114/0xb00 writeback_sb_inodes+0x52b/0xe00 wb_writeback+0x1a7/0x800 wb_workfn+0x12a/0xbd0 process_one_work+0x85a/0x1460 worker_thread+0x5e2/0xfc0 kthread+0x39d/0x750 ret_from_fork+0x30/0x70 ret_from_fork_asm+0x1a/0x30 -> #1 (&fs_info->zoned_meta_io_lock){+.+.}-{4:4}: __mutex_lock+0x1aa/0x1360 btree_write_cache_pages+0x252/0xf90 [btrfs] do_writepages+0x17f/0x7b0 __writeback_single_inode+0x114/0xb00 writeback_sb_inodes+0x52b/0xe00 wb_writeback+0x1a7/0x800 wb_workfn+0x12a/0xbd0 process_one_work+0x85a/0x1460 worker_thread+0x5e2/0xfc0 kthread+0x39d/0x750 ret_from_fork+0x30/0x70 ret_from_fork_asm+0x1a/0x30 -> #0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}: __lock_acquire+0x2f52/0x5ea0 lock_acquire+0x1b1/0x540 __flush_work+0x3ac/0xb60 wb_shutdown+0x15b/0x1f0 bdi_unregister+0x172/0x5b0 del_gendisk+0x841/0xa20 sd_remove+0x85/0x130 device_release_driver_internal+0x368/0x520 bus_remove_device+0x1f1/0x3f0 device_del+0x3bd/0x9c0 __scsi_remove_device+0x272/0x340 scsi_forget_host+0xf7/0x170 scsi_remove_host+0xd2/0x2a0 sdebug_driver_remove+0x52/0x2f0 [scsi_debug] device_release_driver_internal+0x368/0x520 bus_remove_device+0x1f1/0x3f0 device_del+0x3bd/0x9c0 device_unregister+0x13/0xa0 sdebug_do_remove_host+0x1fb/0x290 [scsi_debug] scsi_debug_exit+0x17/0x70 [scsi_debug] __do_sys_delete_module.isra.0+0x321/0x520 do_syscall_64+0x93/0x180 entry_SYSCALL_64_after_hwframe+0x76/0x7e other info that might help us debug this: Chain exists of: (work_completion)(&(&wb->dwork)->work) --> &fs_info->dev_replace.rwsem --> &q->q_usage_counter(queue)torvalds#16 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&q->q_usage_counter(queue)torvalds#16); lock(&fs_info->dev_replace.rwsem); lock(&q->q_usage_counter(queue)torvalds#16); lock((work_completion)(&(&wb->dwork)->work)); *** DEADLOCK *** 5 locks held by modprobe/1110: #0: ffff88811f7bc108 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0x8f/0x520 #1: ffff8881022ee0e0 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_remove_host+0x20/0x2a0 #2: ffff88811b4c4378 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0x8f/0x520 #3: ffff8881205b6f20 (&q->q_usage_counter(queue)torvalds#16){++++}-{0:0}, at: sd_remove+0x85/0x130 #4: ffffffffa3284360 (rcu_read_lock){....}-{1:3}, at: __flush_work+0xda/0xb60 stack backtrace: CPU: 0 UID: 0 PID: 1110 Comm: modprobe Not tainted 6.14.0-rc1 torvalds#252 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-3.fc41 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x6a/0x90 print_circular_bug.cold+0x1e0/0x274 check_noncircular+0x306/0x3f0 ? __pfx_check_noncircular+0x10/0x10 ? mark_lock+0xf5/0x1650 ? __pfx_check_irq_usage+0x10/0x10 ? lockdep_lock+0xca/0x1c0 ? __pfx_lockdep_lock+0x10/0x10 __lock_acquire+0x2f52/0x5ea0 ? __pfx___lock_acquire+0x10/0x10 ? __pfx_mark_lock+0x10/0x10 lock_acquire+0x1b1/0x540 ? __flush_work+0x38f/0xb60 ? __pfx_lock_acquire+0x10/0x10 ? __pfx_lock_release+0x10/0x10 ? mark_held_locks+0x94/0xe0 ? __flush_work+0x38f/0xb60 __flush_work+0x3ac/0xb60 ? __flush_work+0x38f/0xb60 ? __pfx_mark_lock+0x10/0x10 ? __pfx___flush_work+0x10/0x10 ? __pfx_wq_barrier_func+0x10/0x10 ? __pfx___might_resched+0x10/0x10 ? mark_held_locks+0x94/0xe0 wb_shutdown+0x15b/0x1f0 bdi_unregister+0x172/0x5b0 ? __pfx_bdi_unregister+0x10/0x10 ? up_write+0x1ba/0x510 del_gendisk+0x841/0xa20 ? __pfx_del_gendisk+0x10/0x10 ? _raw_spin_unlock_irqrestore+0x35/0x60 ? __pm_runtime_resume+0x79/0x110 sd_remove+0x85/0x130 device_release_driver_internal+0x368/0x520 ? kobject_put+0x5d/0x4a0 bus_remove_device+0x1f1/0x3f0 device_del+0x3bd/0x9c0 ? __pfx_device_del+0x10/0x10 __scsi_remove_device+0x272/0x340 scsi_forget_host+0xf7/0x170 scsi_remove_host+0xd2/0x2a0 sdebug_driver_remove+0x52/0x2f0 [scsi_debug] ? kernfs_remove_by_name_ns+0xc0/0xf0 device_release_driver_internal+0x368/0x520 ? kobject_put+0x5d/0x4a0 bus_remove_device+0x1f1/0x3f0 device_del+0x3bd/0x9c0 ? __pfx_device_del+0x10/0x10 ? __pfx___mutex_unlock_slowpath+0x10/0x10 device_unregister+0x13/0xa0 sdebug_do_remove_host+0x1fb/0x290 [scsi_debug] scsi_debug_exit+0x17/0x70 [scsi_debug] __do_sys_delete_module.isra.0+0x321/0x520 ? __pfx___do_sys_delete_module.isra.0+0x10/0x10 ? __pfx_slab_free_after_rcu_debug+0x10/0x10 ? kasan_save_stack+0x2c/0x50 ? kasan_record_aux_stack+0xa3/0xb0 ? __call_rcu_common.constprop.0+0xc4/0xfb0 ? kmem_cache_free+0x3a0/0x590 ? __x64_sys_close+0x78/0xd0 do_syscall_64+0x93/0x180 ? lock_is_held_type+0xd5/0x130 ? __call_rcu_common.constprop.0+0x3c0/0xfb0 ? lockdep_hardirqs_on+0x78/0x100 ? __call_rcu_common.constprop.0+0x3c0/0xfb0 ? __pfx___call_rcu_common.constprop.0+0x10/0x10 ? kmem_cache_free+0x3a0/0x590 ? lockdep_hardirqs_on_prepare+0x16d/0x400 ? do_syscall_64+0x9f/0x180 ? lockdep_hardirqs_on+0x78/0x100 ? do_syscall_64+0x9f/0x180 ? __pfx___x64_sys_openat+0x10/0x10 ? lockdep_hardirqs_on_prepare+0x16d/0x400 ? do_syscall_64+0x9f/0x180 ? lockdep_hardirqs_on+0x78/0x100 ? do_syscall_64+0x9f/0x180 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f436712b68b RSP: 002b:00007ffe9f1a8658 EFLAGS: 00000206 ORIG_RAX: 00000000000000b0 RAX: ffffffffffffffda RBX: 00005559b367fd80 RCX: 00007f436712b68b RDX: 0000000000000000 RSI: 0000000000000800 RDI: 00005559b367fde8 RBP: 00007ffe9f1a8680 R08: 1999999999999999 R09: 0000000000000000 R10: 00007f43671a5fe0 R11: 0000000000000206 R12: 0000000000000000 R13: 00007ffe9f1a86b0 R14: 0000000000000000 R15: 0000000000000000 </TASK> Reported-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com> CC: <stable@vger.kernel.org> # 6.13+ Tested-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
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[ Upstream commit 1b04495 ] Syzkaller reports a bug as follows: Injecting memory failure for pfn 0x18b00e at process virtual address 0x20ffd000 Memory failure: 0x18b00e: dirty swapcache page still referenced by 2 users Memory failure: 0x18b00e: recovery action for dirty swapcache page: Failed page: refcount:2 mapcount:0 mapping:0000000000000000 index:0x20ffd pfn:0x18b00e memcg:ffff0000dd6d9000 anon flags: 0x5ffffe00482011(locked|dirty|arch_1|swapbacked|hwpoison|node=0|zone=2|lastcpupid=0xfffff) raw: 005ffffe00482011 dead000000000100 dead000000000122 ffff0000e232a7c9 raw: 0000000000020ffd 0000000000000000 00000002ffffffff ffff0000dd6d9000 page dumped because: VM_BUG_ON_FOLIO(!folio_test_uptodate(folio)) ------------[ cut here ]------------ kernel BUG at mm/swap_state.c:184! Internal error: Oops - BUG: 00000000f2000800 [#1] SMP Modules linked in: CPU: 0 PID: 60 Comm: kswapd0 Not tainted 6.6.0-gcb097e7de84e #3 Hardware name: linux,dummy-virt (DT) pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : add_to_swap+0xbc/0x158 lr : add_to_swap+0xbc/0x158 sp : ffff800087f37340 x29: ffff800087f37340 x28: fffffc00052c0380 x27: ffff800087f37780 x26: ffff800087f37490 x25: ffff800087f37c78 x24: ffff800087f377a0 x23: ffff800087f37c50 x22: 0000000000000000 x21: fffffc00052c03b4 x20: 0000000000000000 x19: fffffc00052c0380 x18: 0000000000000000 x17: 296f696c6f662865 x16: 7461646f7470755f x15: 747365745f6f696c x14: 6f6621284f494c4f x13: 0000000000000001 x12: ffff600036d8b97b x11: 1fffe00036d8b97a x10: ffff600036d8b97a x9 : dfff800000000000 x8 : 00009fffc9274686 x7 : ffff0001b6c5cbd3 x6 : 0000000000000001 x5 : ffff0000c25896c0 x4 : 0000000000000000 x3 : 0000000000000000 x2 : 0000000000000000 x1 : ffff0000c25896c0 x0 : 0000000000000000 Call trace: add_to_swap+0xbc/0x158 shrink_folio_list+0x12ac/0x2648 shrink_inactive_list+0x318/0x948 shrink_lruvec+0x450/0x720 shrink_node_memcgs+0x280/0x4a8 shrink_node+0x128/0x978 balance_pgdat+0x4f0/0xb20 kswapd+0x228/0x438 kthread+0x214/0x230 ret_from_fork+0x10/0x20 I can reproduce this issue with the following steps: 1) When a dirty swapcache page is isolated by reclaim process and the page isn't locked, inject memory failure for the page. me_swapcache_dirty() clears uptodate flag and tries to delete from lru, but fails. Reclaim process will put the hwpoisoned page back to lru. 2) The process that maps the hwpoisoned page exits, the page is deleted the page will never be freed and will be in the lru forever. 3) If we trigger a reclaim again and tries to reclaim the page, add_to_swap() will trigger VM_BUG_ON_FOLIO due to the uptodate flag is cleared. To fix it, skip the hwpoisoned page in shrink_folio_list(). Besides, the hwpoison folio may not be unmapped by hwpoison_user_mappings() yet, unmap it in shrink_folio_list(), otherwise the folio will fail to be unmaped by hwpoison_user_mappings() since the folio isn't in lru list. Link: https://lkml.kernel.org/r/20250318083939.987651-3-tujinjiang@huawei.com Signed-off-by: Jinjiang Tu <tujinjiang@huawei.com> Acked-by: Miaohe Lin <linmiaohe@huawei.com> Cc: David Hildenbrand <david@redhat.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Nanyong Sun <sunnanyong@huawei.com> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: <stable@vger,kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
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May 9, 2025
[ Upstream commit 866bafa ] There is a potential deadlock if we do report zones in an IO context, detailed in below lockdep report. When one process do a report zones and another process freezes the block device, the report zones side cannot allocate a tag because the freeze is already started. This can thus result in new block group creation to hang forever, blocking the write path. Thankfully, a new block group should be created on empty zones. So, reporting the zones is not necessary and we can set the write pointer = 0 and load the zone capacity from the block layer using bdev_zone_capacity() helper. ====================================================== WARNING: possible circular locking dependency detected 6.14.0-rc1 torvalds#252 Not tainted ------------------------------------------------------ modprobe/1110 is trying to acquire lock: ffff888100ac83e0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: __flush_work+0x38f/0xb60 but task is already holding lock: ffff8881205b6f20 (&q->q_usage_counter(queue)torvalds#16){++++}-{0:0}, at: sd_remove+0x85/0x130 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&q->q_usage_counter(queue)torvalds#16){++++}-{0:0}: blk_queue_enter+0x3d9/0x500 blk_mq_alloc_request+0x47d/0x8e0 scsi_execute_cmd+0x14f/0xb80 sd_zbc_do_report_zones+0x1c1/0x470 sd_zbc_report_zones+0x362/0xd60 blkdev_report_zones+0x1b1/0x2e0 btrfs_get_dev_zones+0x215/0x7e0 [btrfs] btrfs_load_block_group_zone_info+0x6d2/0x2c10 [btrfs] btrfs_make_block_group+0x36b/0x870 [btrfs] btrfs_create_chunk+0x147d/0x2320 [btrfs] btrfs_chunk_alloc+0x2ce/0xcf0 [btrfs] start_transaction+0xce6/0x1620 [btrfs] btrfs_uuid_scan_kthread+0x4ee/0x5b0 [btrfs] kthread+0x39d/0x750 ret_from_fork+0x30/0x70 ret_from_fork_asm+0x1a/0x30 -> #2 (&fs_info->dev_replace.rwsem){++++}-{4:4}: down_read+0x9b/0x470 btrfs_map_block+0x2ce/0x2ce0 [btrfs] btrfs_submit_chunk+0x2d4/0x16c0 [btrfs] btrfs_submit_bbio+0x16/0x30 [btrfs] btree_write_cache_pages+0xb5a/0xf90 [btrfs] do_writepages+0x17f/0x7b0 __writeback_single_inode+0x114/0xb00 writeback_sb_inodes+0x52b/0xe00 wb_writeback+0x1a7/0x800 wb_workfn+0x12a/0xbd0 process_one_work+0x85a/0x1460 worker_thread+0x5e2/0xfc0 kthread+0x39d/0x750 ret_from_fork+0x30/0x70 ret_from_fork_asm+0x1a/0x30 -> #1 (&fs_info->zoned_meta_io_lock){+.+.}-{4:4}: __mutex_lock+0x1aa/0x1360 btree_write_cache_pages+0x252/0xf90 [btrfs] do_writepages+0x17f/0x7b0 __writeback_single_inode+0x114/0xb00 writeback_sb_inodes+0x52b/0xe00 wb_writeback+0x1a7/0x800 wb_workfn+0x12a/0xbd0 process_one_work+0x85a/0x1460 worker_thread+0x5e2/0xfc0 kthread+0x39d/0x750 ret_from_fork+0x30/0x70 ret_from_fork_asm+0x1a/0x30 -> #0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}: __lock_acquire+0x2f52/0x5ea0 lock_acquire+0x1b1/0x540 __flush_work+0x3ac/0xb60 wb_shutdown+0x15b/0x1f0 bdi_unregister+0x172/0x5b0 del_gendisk+0x841/0xa20 sd_remove+0x85/0x130 device_release_driver_internal+0x368/0x520 bus_remove_device+0x1f1/0x3f0 device_del+0x3bd/0x9c0 __scsi_remove_device+0x272/0x340 scsi_forget_host+0xf7/0x170 scsi_remove_host+0xd2/0x2a0 sdebug_driver_remove+0x52/0x2f0 [scsi_debug] device_release_driver_internal+0x368/0x520 bus_remove_device+0x1f1/0x3f0 device_del+0x3bd/0x9c0 device_unregister+0x13/0xa0 sdebug_do_remove_host+0x1fb/0x290 [scsi_debug] scsi_debug_exit+0x17/0x70 [scsi_debug] __do_sys_delete_module.isra.0+0x321/0x520 do_syscall_64+0x93/0x180 entry_SYSCALL_64_after_hwframe+0x76/0x7e other info that might help us debug this: Chain exists of: (work_completion)(&(&wb->dwork)->work) --> &fs_info->dev_replace.rwsem --> &q->q_usage_counter(queue)torvalds#16 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&q->q_usage_counter(queue)torvalds#16); lock(&fs_info->dev_replace.rwsem); lock(&q->q_usage_counter(queue)torvalds#16); lock((work_completion)(&(&wb->dwork)->work)); *** DEADLOCK *** 5 locks held by modprobe/1110: #0: ffff88811f7bc108 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0x8f/0x520 #1: ffff8881022ee0e0 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_remove_host+0x20/0x2a0 #2: ffff88811b4c4378 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0x8f/0x520 #3: ffff8881205b6f20 (&q->q_usage_counter(queue)torvalds#16){++++}-{0:0}, at: sd_remove+0x85/0x130 #4: ffffffffa3284360 (rcu_read_lock){....}-{1:3}, at: __flush_work+0xda/0xb60 stack backtrace: CPU: 0 UID: 0 PID: 1110 Comm: modprobe Not tainted 6.14.0-rc1 torvalds#252 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-3.fc41 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x6a/0x90 print_circular_bug.cold+0x1e0/0x274 check_noncircular+0x306/0x3f0 ? __pfx_check_noncircular+0x10/0x10 ? mark_lock+0xf5/0x1650 ? __pfx_check_irq_usage+0x10/0x10 ? lockdep_lock+0xca/0x1c0 ? __pfx_lockdep_lock+0x10/0x10 __lock_acquire+0x2f52/0x5ea0 ? __pfx___lock_acquire+0x10/0x10 ? __pfx_mark_lock+0x10/0x10 lock_acquire+0x1b1/0x540 ? __flush_work+0x38f/0xb60 ? __pfx_lock_acquire+0x10/0x10 ? __pfx_lock_release+0x10/0x10 ? mark_held_locks+0x94/0xe0 ? __flush_work+0x38f/0xb60 __flush_work+0x3ac/0xb60 ? __flush_work+0x38f/0xb60 ? __pfx_mark_lock+0x10/0x10 ? __pfx___flush_work+0x10/0x10 ? __pfx_wq_barrier_func+0x10/0x10 ? __pfx___might_resched+0x10/0x10 ? mark_held_locks+0x94/0xe0 wb_shutdown+0x15b/0x1f0 bdi_unregister+0x172/0x5b0 ? __pfx_bdi_unregister+0x10/0x10 ? up_write+0x1ba/0x510 del_gendisk+0x841/0xa20 ? __pfx_del_gendisk+0x10/0x10 ? _raw_spin_unlock_irqrestore+0x35/0x60 ? __pm_runtime_resume+0x79/0x110 sd_remove+0x85/0x130 device_release_driver_internal+0x368/0x520 ? kobject_put+0x5d/0x4a0 bus_remove_device+0x1f1/0x3f0 device_del+0x3bd/0x9c0 ? __pfx_device_del+0x10/0x10 __scsi_remove_device+0x272/0x340 scsi_forget_host+0xf7/0x170 scsi_remove_host+0xd2/0x2a0 sdebug_driver_remove+0x52/0x2f0 [scsi_debug] ? kernfs_remove_by_name_ns+0xc0/0xf0 device_release_driver_internal+0x368/0x520 ? kobject_put+0x5d/0x4a0 bus_remove_device+0x1f1/0x3f0 device_del+0x3bd/0x9c0 ? __pfx_device_del+0x10/0x10 ? __pfx___mutex_unlock_slowpath+0x10/0x10 device_unregister+0x13/0xa0 sdebug_do_remove_host+0x1fb/0x290 [scsi_debug] scsi_debug_exit+0x17/0x70 [scsi_debug] __do_sys_delete_module.isra.0+0x321/0x520 ? __pfx___do_sys_delete_module.isra.0+0x10/0x10 ? __pfx_slab_free_after_rcu_debug+0x10/0x10 ? kasan_save_stack+0x2c/0x50 ? kasan_record_aux_stack+0xa3/0xb0 ? __call_rcu_common.constprop.0+0xc4/0xfb0 ? kmem_cache_free+0x3a0/0x590 ? __x64_sys_close+0x78/0xd0 do_syscall_64+0x93/0x180 ? lock_is_held_type+0xd5/0x130 ? __call_rcu_common.constprop.0+0x3c0/0xfb0 ? lockdep_hardirqs_on+0x78/0x100 ? __call_rcu_common.constprop.0+0x3c0/0xfb0 ? __pfx___call_rcu_common.constprop.0+0x10/0x10 ? kmem_cache_free+0x3a0/0x590 ? lockdep_hardirqs_on_prepare+0x16d/0x400 ? do_syscall_64+0x9f/0x180 ? lockdep_hardirqs_on+0x78/0x100 ? do_syscall_64+0x9f/0x180 ? __pfx___x64_sys_openat+0x10/0x10 ? lockdep_hardirqs_on_prepare+0x16d/0x400 ? do_syscall_64+0x9f/0x180 ? lockdep_hardirqs_on+0x78/0x100 ? do_syscall_64+0x9f/0x180 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f436712b68b RSP: 002b:00007ffe9f1a8658 EFLAGS: 00000206 ORIG_RAX: 00000000000000b0 RAX: ffffffffffffffda RBX: 00005559b367fd80 RCX: 00007f436712b68b RDX: 0000000000000000 RSI: 0000000000000800 RDI: 00005559b367fde8 RBP: 00007ffe9f1a8680 R08: 1999999999999999 R09: 0000000000000000 R10: 00007f43671a5fe0 R11: 0000000000000206 R12: 0000000000000000 R13: 00007ffe9f1a86b0 R14: 0000000000000000 R15: 0000000000000000 </TASK> Reported-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com> CC: <stable@vger.kernel.org> # 6.13+ Tested-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
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…ux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 fixes for 6.15, round #3 - Avoid use of uninitialized memcache pointer in user_mem_abort() - Always set HCR_EL2.xMO bits when running in VHE, allowing interrupts to be taken while TGE=0 and fixing an ugly bug on AmpereOne that occurs when taking an interrupt while clearing the xMO bits (AC03_CPU_36) - Prevent VMMs from hiding support for AArch64 at any EL virtualized by KVM - Save/restore the host value for HCRX_EL2 instead of restoring an incorrect fixed value - Make host_stage2_set_owner_locked() check that the entire requested range is memory rather than just the first page
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Jun 10, 2025
This patch enables support for DYNAMIC_FTRACE_WITH_CALL_OPS on RISC-V. This allows each ftrace callsite to provide an ftrace_ops to the common ftrace trampoline, allowing each callsite to invoke distinct tracer functions without the need to fall back to list processing or to allocate custom trampolines for each callsite. This significantly speeds up cases where multiple distinct trace functions are used and callsites are mostly traced by a single tracer. The idea and most of the implementation is taken from the ARM64's implementation of the same feature. The idea is to place a pointer to the ftrace_ops as a literal at a fixed offset from the function entry point, which can be recovered by the common ftrace trampoline. We use -fpatchable-function-entry to reserve 8 bytes above the function entry by emitting 2 4 byte or 4 2 byte nops depending on the presence of CONFIG_RISCV_ISA_C. These 8 bytes are patched at runtime with a pointer to the associated ftrace_ops for that callsite. Functions are aligned to 8 bytes to make sure that the accesses to this literal are atomic. This approach allows for directly invoking ftrace_ops::func even for ftrace_ops which are dynamically-allocated (or part of a module), without going via ftrace_ops_list_func. We've benchamrked this with the ftrace_ops sample module on Spacemit K1 Jupiter: Without this patch: baseline (Linux rivos 6.14.0-09584-g7d06015d936c #3 SMP Sat Mar 29 +-----------------------+-----------------+----------------------------+ | Number of tracers | Total time (ns) | Per-call average time | |-----------------------+-----------------+----------------------------| | Relevant | Irrelevant | 100000 calls | Total (ns) | Overhead (ns) | |----------+------------+-----------------+------------+---------------| | 0 | 0 | 1357958 | 13 | - | | 0 | 1 | 1302375 | 13 | - | | 0 | 2 | 1302375 | 13 | - | | 0 | 10 | 1379084 | 13 | - | | 0 | 100 | 1302458 | 13 | - | | 0 | 200 | 1302333 | 13 | - | |----------+------------+-----------------+------------+---------------| | 1 | 0 | 13677833 | 136 | 123 | | 1 | 1 | 18500916 | 185 | 172 | | 1 | 2 | 2285645 | 228 | 215 | | 1 | 10 | 58824709 | 588 | 575 | | 1 | 100 | 505141584 | 5051 | 5038 | | 1 | 200 | 1580473126 | 15804 | 15791 | |----------+------------+-----------------+------------+---------------| | 1 | 0 | 13561000 | 135 | 122 | | 2 | 0 | 19707292 | 197 | 184 | | 10 | 0 | 67774750 | 677 | 664 | | 100 | 0 | 714123125 | 7141 | 7128 | | 200 | 0 | 1918065668 | 19180 | 19167 | +----------+------------+-----------------+------------+---------------+ Note: per-call overhead is estimated relative to the baseline case with 0 relevant tracers and 0 irrelevant tracers. With this patch: v4-rc4 (Linux rivos 6.14.0-09598-gd75747611c93 #4 SMP Sat Mar 29 +-----------------------+-----------------+----------------------------+ | Number of tracers | Total time (ns) | Per-call average time | |-----------------------+-----------------+----------------------------| | Relevant | Irrelevant | 100000 calls | Total (ns) | Overhead (ns) | |----------+------------+-----------------+------------+---------------| | 0 | 0 | 1459917 | 14 | - | | 0 | 1 | 1408000 | 14 | - | | 0 | 2 | 1383792 | 13 | - | | 0 | 10 | 1430709 | 14 | - | | 0 | 100 | 1383791 | 13 | - | | 0 | 200 | 1383750 | 13 | - | |----------+------------+-----------------+------------+---------------| | 1 | 0 | 5238041 | 52 | 38 | | 1 | 1 | 5228542 | 52 | 38 | | 1 | 2 | 5325917 | 53 | 40 | | 1 | 10 | 5299667 | 52 | 38 | | 1 | 100 | 5245250 | 52 | 39 | | 1 | 200 | 5238459 | 52 | 39 | |----------+------------+-----------------+------------+---------------| | 1 | 0 | 5239083 | 52 | 38 | | 2 | 0 | 19449417 | 194 | 181 | | 10 | 0 | 67718584 | 677 | 663 | | 100 | 0 | 709840708 | 7098 | 7085 | | 200 | 0 | 2203580626 | 22035 | 22022 | +----------+------------+-----------------+------------+---------------+ Note: per-call overhead is estimated relative to the baseline case with 0 relevant tracers and 0 irrelevant tracers. As can be seen from the above: a) Whenever there is a single relevant tracer function associated with a tracee, the overhead of invoking the tracer is constant, and does not scale with the number of tracers which are *not* associated with that tracee. b) The overhead for a single relevant tracer has dropped to ~1/3 of the overhead prior to this series (from 122ns to 38ns). This is largely due to permitting calls to dynamically-allocated ftrace_ops without going through ftrace_ops_list_func. Signed-off-by: Puranjay Mohan <puranjay12@gmail.com> [update kconfig, asm, refactor] Signed-off-by: Andy Chiu <andybnac@gmail.com> Tested-by: Björn Töpel <bjorn@rivosinc.com> Link: https://lore.kernel.org/r/20250407180838.42877-10-andybnac@gmail.com Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
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[ Upstream commit ee684de ] As shown in [1], it is possible to corrupt a BPF ELF file such that arbitrary BPF instructions are loaded by libbpf. This can be done by setting a symbol (BPF program) section offset to a large (unsigned) number such that <section start + symbol offset> overflows and points before the section data in the memory. Consider the situation below where: - prog_start = sec_start + symbol_offset <-- size_t overflow here - prog_end = prog_start + prog_size prog_start sec_start prog_end sec_end | | | | v v v v .....................|################################|............ The report in [1] also provides a corrupted BPF ELF which can be used as a reproducer: $ readelf -S crash Section Headers: [Nr] Name Type Address Offset Size EntSize Flags Link Info Align ... [ 2] uretprobe.mu[...] PROGBITS 0000000000000000 00000040 0000000000000068 0000000000000000 AX 0 0 8 $ readelf -s crash Symbol table '.symtab' contains 8 entries: Num: Value Size Type Bind Vis Ndx Name ... 6: ffffffffffffffb8 104 FUNC GLOBAL DEFAULT 2 handle_tp Here, the handle_tp prog has section offset ffffffffffffffb8, i.e. will point before the actual memory where section 2 is allocated. This is also reported by AddressSanitizer: ================================================================= ==1232==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x7c7302fe0000 at pc 0x7fc3046e4b77 bp 0x7ffe64677cd0 sp 0x7ffe64677490 READ of size 104 at 0x7c7302fe0000 thread T0 #0 0x7fc3046e4b76 in memcpy (/lib64/libasan.so.8+0xe4b76) #1 0x00000040df3e in bpf_object__init_prog /src/libbpf/src/libbpf.c:856 #2 0x00000040df3e in bpf_object__add_programs /src/libbpf/src/libbpf.c:928 #3 0x00000040df3e in bpf_object__elf_collect /src/libbpf/src/libbpf.c:3930 #4 0x00000040df3e in bpf_object_open /src/libbpf/src/libbpf.c:8067 #5 0x00000040f176 in bpf_object__open_file /src/libbpf/src/libbpf.c:8090 #6 0x000000400c16 in main /poc/poc.c:8 #7 0x7fc3043d25b4 in __libc_start_call_main (/lib64/libc.so.6+0x35b4) #8 0x7fc3043d2667 in __libc_start_main@@GLIBC_2.34 (/lib64/libc.so.6+0x3667) #9 0x000000400b34 in _start (/poc/poc+0x400b34) 0x7c7302fe0000 is located 64 bytes before 104-byte region [0x7c7302fe0040,0x7c7302fe00a8) allocated by thread T0 here: #0 0x7fc3046e716b in malloc (/lib64/libasan.so.8+0xe716b) #1 0x7fc3045ee600 in __libelf_set_rawdata_wrlock (/lib64/libelf.so.1+0xb600) #2 0x7fc3045ef018 in __elf_getdata_rdlock (/lib64/libelf.so.1+0xc018) #3 0x00000040642f in elf_sec_data /src/libbpf/src/libbpf.c:3740 The problem here is that currently, libbpf only checks that the program end is within the section bounds. There used to be a check `while (sec_off < sec_sz)` in bpf_object__add_programs, however, it was removed by commit 6245947 ("libbpf: Allow gaps in BPF program sections to support overriden weak functions"). Add a check for detecting the overflow of `sec_off + prog_sz` to bpf_object__init_prog to fix this issue. [1] https://github.com/lmarch2/poc/blob/main/libbpf/libbpf.md Fixes: 6245947 ("libbpf: Allow gaps in BPF program sections to support overriden weak functions") Reported-by: lmarch2 <2524158037@qq.com> Signed-off-by: Viktor Malik <vmalik@redhat.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Link: https://github.com/lmarch2/poc/blob/main/libbpf/libbpf.md Link: https://lore.kernel.org/bpf/20250415155014.397603-1-vmalik@redhat.com Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit c98cc97 upstream. Running a modified trace-cmd record --nosplice where it does a mmap of the ring buffer when '--nosplice' is set, caused the following lockdep splat: ====================================================== WARNING: possible circular locking dependency detected 6.15.0-rc7-test-00002-gfb7d03d8a82f torvalds#551 Not tainted ------------------------------------------------------ trace-cmd/1113 is trying to acquire lock: ffff888100062888 (&buffer->mutex){+.+.}-{4:4}, at: ring_buffer_map+0x11c/0xe70 but task is already holding lock: ffff888100a5f9f8 (&cpu_buffer->mapping_lock){+.+.}-{4:4}, at: ring_buffer_map+0xcf/0xe70 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #5 (&cpu_buffer->mapping_lock){+.+.}-{4:4}: __mutex_lock+0x192/0x18c0 ring_buffer_map+0xcf/0xe70 tracing_buffers_mmap+0x1c4/0x3b0 __mmap_region+0xd8d/0x1f70 do_mmap+0x9d7/0x1010 vm_mmap_pgoff+0x20b/0x390 ksys_mmap_pgoff+0x2e9/0x440 do_syscall_64+0x79/0x1c0 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #4 (&mm->mmap_lock){++++}-{4:4}: __might_fault+0xa5/0x110 _copy_to_user+0x22/0x80 _perf_ioctl+0x61b/0x1b70 perf_ioctl+0x62/0x90 __x64_sys_ioctl+0x134/0x190 do_syscall_64+0x79/0x1c0 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #3 (&cpuctx_mutex){+.+.}-{4:4}: __mutex_lock+0x192/0x18c0 perf_event_init_cpu+0x325/0x7c0 perf_event_init+0x52a/0x5b0 start_kernel+0x263/0x3e0 x86_64_start_reservations+0x24/0x30 x86_64_start_kernel+0x95/0xa0 common_startup_64+0x13e/0x141 -> #2 (pmus_lock){+.+.}-{4:4}: __mutex_lock+0x192/0x18c0 perf_event_init_cpu+0xb7/0x7c0 cpuhp_invoke_callback+0x2c0/0x1030 __cpuhp_invoke_callback_range+0xbf/0x1f0 _cpu_up+0x2e7/0x690 cpu_up+0x117/0x170 cpuhp_bringup_mask+0xd5/0x120 bringup_nonboot_cpus+0x13d/0x170 smp_init+0x2b/0xf0 kernel_init_freeable+0x441/0x6d0 kernel_init+0x1e/0x160 ret_from_fork+0x34/0x70 ret_from_fork_asm+0x1a/0x30 -> #1 (cpu_hotplug_lock){++++}-{0:0}: cpus_read_lock+0x2a/0xd0 ring_buffer_resize+0x610/0x14e0 __tracing_resize_ring_buffer.part.0+0x42/0x120 tracing_set_tracer+0x7bd/0xa80 tracing_set_trace_write+0x132/0x1e0 vfs_write+0x21c/0xe80 ksys_write+0xf9/0x1c0 do_syscall_64+0x79/0x1c0 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #0 (&buffer->mutex){+.+.}-{4:4}: __lock_acquire+0x1405/0x2210 lock_acquire+0x174/0x310 __mutex_lock+0x192/0x18c0 ring_buffer_map+0x11c/0xe70 tracing_buffers_mmap+0x1c4/0x3b0 __mmap_region+0xd8d/0x1f70 do_mmap+0x9d7/0x1010 vm_mmap_pgoff+0x20b/0x390 ksys_mmap_pgoff+0x2e9/0x440 do_syscall_64+0x79/0x1c0 entry_SYSCALL_64_after_hwframe+0x76/0x7e other info that might help us debug this: Chain exists of: &buffer->mutex --> &mm->mmap_lock --> &cpu_buffer->mapping_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&cpu_buffer->mapping_lock); lock(&mm->mmap_lock); lock(&cpu_buffer->mapping_lock); lock(&buffer->mutex); *** DEADLOCK *** 2 locks held by trace-cmd/1113: #0: ffff888106b847e0 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x192/0x390 #1: ffff888100a5f9f8 (&cpu_buffer->mapping_lock){+.+.}-{4:4}, at: ring_buffer_map+0xcf/0xe70 stack backtrace: CPU: 5 UID: 0 PID: 1113 Comm: trace-cmd Not tainted 6.15.0-rc7-test-00002-gfb7d03d8a82f torvalds#551 PREEMPT Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x6e/0xa0 print_circular_bug.cold+0x178/0x1be check_noncircular+0x146/0x160 __lock_acquire+0x1405/0x2210 lock_acquire+0x174/0x310 ? ring_buffer_map+0x11c/0xe70 ? ring_buffer_map+0x11c/0xe70 ? __mutex_lock+0x169/0x18c0 __mutex_lock+0x192/0x18c0 ? ring_buffer_map+0x11c/0xe70 ? ring_buffer_map+0x11c/0xe70 ? function_trace_call+0x296/0x370 ? __pfx___mutex_lock+0x10/0x10 ? __pfx_function_trace_call+0x10/0x10 ? __pfx___mutex_lock+0x10/0x10 ? _raw_spin_unlock+0x2d/0x50 ? ring_buffer_map+0x11c/0xe70 ? ring_buffer_map+0x11c/0xe70 ? __mutex_lock+0x5/0x18c0 ring_buffer_map+0x11c/0xe70 ? do_raw_spin_lock+0x12d/0x270 ? find_held_lock+0x2b/0x80 ? _raw_spin_unlock+0x2d/0x50 ? rcu_is_watching+0x15/0xb0 ? _raw_spin_unlock+0x2d/0x50 ? trace_preempt_on+0xd0/0x110 tracing_buffers_mmap+0x1c4/0x3b0 __mmap_region+0xd8d/0x1f70 ? ring_buffer_lock_reserve+0x99/0xff0 ? __pfx___mmap_region+0x10/0x10 ? ring_buffer_lock_reserve+0x99/0xff0 ? __pfx_ring_buffer_lock_reserve+0x10/0x10 ? __pfx_ring_buffer_lock_reserve+0x10/0x10 ? bpf_lsm_mmap_addr+0x4/0x10 ? security_mmap_addr+0x46/0xd0 ? lock_is_held_type+0xd9/0x130 do_mmap+0x9d7/0x1010 ? 0xffffffffc0370095 ? __pfx_do_mmap+0x10/0x10 vm_mmap_pgoff+0x20b/0x390 ? __pfx_vm_mmap_pgoff+0x10/0x10 ? 0xffffffffc0370095 ksys_mmap_pgoff+0x2e9/0x440 do_syscall_64+0x79/0x1c0 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7fb0963a7de2 Code: 00 00 00 0f 1f 44 00 00 41 f7 c1 ff 0f 00 00 75 27 55 89 cd 53 48 89 fb 48 85 ff 74 3b 41 89 ea 48 89 df b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 76 5b 5d c3 0f 1f 00 48 8b 05 e1 9f 0d 00 64 RSP: 002b:00007ffdcc8fb878 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb0963a7de2 RDX: 0000000000000001 RSI: 0000000000001000 RDI: 0000000000000000 RBP: 0000000000000001 R08: 0000000000000006 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffdcc8fbe68 R14: 00007fb096628000 R15: 00005633e01a5c90 </TASK> The issue is that cpus_read_lock() is taken within buffer->mutex. The memory mapped pages are taken with the mmap_lock held. The buffer->mutex is taken within the cpu_buffer->mapping_lock. There's quite a chain with all these locks, where the deadlock can be fixed by moving the cpus_read_lock() outside the taking of the buffer->mutex. Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Vincent Donnefort <vdonnefort@google.com> Link: https://lore.kernel.org/20250527105820.0f45d045@gandalf.local.home Fixes: 117c392 ("ring-buffer: Introducing ring-buffer mapping functions") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit eedf3e3 ] ACPICA commit 1c28da2242783579d59767617121035dafba18c3 This was originally done in NetBSD: NetBSD/src@b69d1ac and is the correct alternative to the smattering of `memcpy`s I previously contributed to this repository. This also sidesteps the newly strict checks added in UBSAN: llvm/llvm-project@7926744 Before this change we see the following UBSAN stack trace in Fuchsia: #0 0x000021afcfdeca5e in acpi_rs_get_address_common(struct acpi_resource*, union aml_resource*) ../../third_party/acpica/source/components/resources/rsaddr.c:329 <platform-bus-x86.so>+0x6aca5e #1.2 0x000021982bc4af3c in ubsan_get_stack_trace() compiler-rt/lib/ubsan/ubsan_diag.cpp:41 <libclang_rt.asan.so>+0x41f3c #1.1 0x000021982bc4af3c in maybe_print_stack_trace() compiler-rt/lib/ubsan/ubsan_diag.cpp:51 <libclang_rt.asan.so>+0x41f3c #1 0x000021982bc4af3c in ~scoped_report() compiler-rt/lib/ubsan/ubsan_diag.cpp:395 <libclang_rt.asan.so>+0x41f3c #2 0x000021982bc4bb6f in handletype_mismatch_impl() compiler-rt/lib/ubsan/ubsan_handlers.cpp:137 <libclang_rt.asan.so>+0x42b6f #3 0x000021982bc4b723 in __ubsan_handle_type_mismatch_v1 compiler-rt/lib/ubsan/ubsan_handlers.cpp:142 <libclang_rt.asan.so>+0x42723 #4 0x000021afcfdeca5e in acpi_rs_get_address_common(struct acpi_resource*, union aml_resource*) ../../third_party/acpica/source/components/resources/rsaddr.c:329 <platform-bus-x86.so>+0x6aca5e #5 0x000021afcfdf2089 in acpi_rs_convert_aml_to_resource(struct acpi_resource*, union aml_resource*, struct acpi_rsconvert_info*) ../../third_party/acpica/source/components/resources/rsmisc.c:355 <platform-bus-x86.so>+0x6b2089 #6 0x000021afcfded169 in acpi_rs_convert_aml_to_resources(u8*, u32, u32, u8, void**) ../../third_party/acpica/source/components/resources/rslist.c:137 <platform-bus-x86.so>+0x6ad169 #7 0x000021afcfe2d24a in acpi_ut_walk_aml_resources(struct acpi_walk_state*, u8*, acpi_size, acpi_walk_aml_callback, void**) ../../third_party/acpica/source/components/utilities/utresrc.c:237 <platform-bus-x86.so>+0x6ed24a #8 0x000021afcfde66b7 in acpi_rs_create_resource_list(union acpi_operand_object*, struct acpi_buffer*) ../../third_party/acpica/source/components/resources/rscreate.c:199 <platform-bus-x86.so>+0x6a66b7 #9 0x000021afcfdf6979 in acpi_rs_get_method_data(acpi_handle, const char*, struct acpi_buffer*) ../../third_party/acpica/source/components/resources/rsutils.c:770 <platform-bus-x86.so>+0x6b6979 torvalds#10 0x000021afcfdf708f in acpi_walk_resources(acpi_handle, char*, acpi_walk_resource_callback, void*) ../../third_party/acpica/source/components/resources/rsxface.c:731 <platform-bus-x86.so>+0x6b708f torvalds#11 0x000021afcfa95dcf in acpi::acpi_impl::walk_resources(acpi::acpi_impl*, acpi_handle, const char*, acpi::Acpi::resources_callable) ../../src/devices/board/lib/acpi/acpi-impl.cc:41 <platform-bus-x86.so>+0x355dcf torvalds#12 0x000021afcfaa8278 in acpi::device_builder::gather_resources(acpi::device_builder*, acpi::Acpi*, fidl::any_arena&, acpi::Manager*, acpi::device_builder::gather_resources_callback) ../../src/devices/board/lib/acpi/device-builder.cc:84 <platform-bus-x86.so>+0x368278 torvalds#13 0x000021afcfbddb87 in acpi::Manager::configure_discovered_devices(acpi::Manager*) ../../src/devices/board/lib/acpi/manager.cc:75 <platform-bus-x86.so>+0x49db87 torvalds#14 0x000021afcf99091d in publish_acpi_devices(acpi::Manager*, zx_device_t*, zx_device_t*) ../../src/devices/board/drivers/x86/acpi-nswalk.cc:95 <platform-bus-x86.so>+0x25091d torvalds#15 0x000021afcf9c1d4e in x86::X86::do_init(x86::X86*) ../../src/devices/board/drivers/x86/x86.cc:60 <platform-bus-x86.so>+0x281d4e torvalds#16 0x000021afcf9e33ad in λ(x86::X86::ddk_init::(anon class)*) ../../src/devices/board/drivers/x86/x86.cc:77 <platform-bus-x86.so>+0x2a33ad torvalds#17 0x000021afcf9e313e in fit::internal::target<(lambda at../../src/devices/board/drivers/x86/x86.cc:76:19), false, false, std::__2::allocator<std::byte>, void>::invoke(void*) ../../sdk/lib/fit/include/lib/fit/internal/function.h:183 <platform-bus-x86.so>+0x2a313e torvalds#18 0x000021afcfbab4c7 in fit::internal::function_base<16UL, false, void(), std::__2::allocator<std::byte>>::invoke(const fit::internal::function_base<16UL, false, void (), std::__2::allocator<std::byte> >*) ../../sdk/lib/fit/include/lib/fit/internal/function.h:522 <platform-bus-x86.so>+0x46b4c7 torvalds#19 0x000021afcfbab342 in fit::function_impl<16UL, false, void(), std::__2::allocator<std::byte>>::operator()(const fit::function_impl<16UL, false, void (), std::__2::allocator<std::byte> >*) ../../sdk/lib/fit/include/lib/fit/function.h:315 <platform-bus-x86.so>+0x46b342 torvalds#20 0x000021afcfcd98c3 in async::internal::retained_task::Handler(async_dispatcher_t*, async_task_t*, zx_status_t) ../../sdk/lib/async/task.cc:24 <platform-bus-x86.so>+0x5998c3 torvalds#21 0x00002290f9924616 in λ(const driver_runtime::Dispatcher::post_task::(anon class)*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, zx_status_t) ../../src/devices/bin/driver_runtime/dispatcher.cc:789 <libdriver_runtime.so>+0x10a616 torvalds#22 0x00002290f9924323 in fit::internal::target<(lambda at../../src/devices/bin/driver_runtime/dispatcher.cc:788:7), true, false, std::__2::allocator<std::byte>, void, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request>>, int>::invoke(void*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int) ../../sdk/lib/fit/include/lib/fit/internal/function.h:128 <libdriver_runtime.so>+0x10a323 torvalds#23 0x00002290f9904b76 in fit::internal::function_base<24UL, true, void(std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request>>, int), std::__2::allocator<std::byte>>::invoke(const fit::internal::function_base<24UL, true, void (std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int) ../../sdk/lib/fit/include/lib/fit/internal/function.h:522 <libdriver_runtime.so>+0xeab76 torvalds#24 0x00002290f9904831 in fit::callback_impl<24UL, true, void(std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request>>, int), std::__2::allocator<std::byte>>::operator()(fit::callback_impl<24UL, true, void (std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int) ../../sdk/lib/fit/include/lib/fit/function.h:471 <libdriver_runtime.so>+0xea831 torvalds#25 0x00002290f98d5adc in driver_runtime::callback_request::Call(driver_runtime::callback_request*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, zx_status_t) ../../src/devices/bin/driver_runtime/callback_request.h:74 <libdriver_runtime.so>+0xbbadc torvalds#26 0x00002290f98e1e58 in driver_runtime::Dispatcher::dispatch_callback(driver_runtime::Dispatcher*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >) ../../src/devices/bin/driver_runtime/dispatcher.cc:1248 <libdriver_runtime.so>+0xc7e58 torvalds#27 0x00002290f98e4159 in driver_runtime::Dispatcher::dispatch_callbacks(driver_runtime::Dispatcher*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../src/devices/bin/driver_runtime/dispatcher.cc:1308 <libdriver_runtime.so>+0xca159 torvalds#28 0x00002290f9918414 in λ(const driver_runtime::Dispatcher::create_with_adder::(anon class)*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../src/devices/bin/driver_runtime/dispatcher.cc:353 <libdriver_runtime.so>+0xfe414 torvalds#29 0x00002290f991812d in fit::internal::target<(lambda at../../src/devices/bin/driver_runtime/dispatcher.cc:351:7), true, false, std::__2::allocator<std::byte>, void, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter>>, fbl::ref_ptr<driver_runtime::Dispatcher>>::invoke(void*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../sdk/lib/fit/include/lib/fit/internal/function.h:128 <libdriver_runtime.so>+0xfe12d torvalds#30 0x00002290f9906fc7 in fit::internal::function_base<8UL, true, void(std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter>>, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte>>::invoke(const fit::internal::function_base<8UL, true, void (std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../sdk/lib/fit/include/lib/fit/internal/function.h:522 <libdriver_runtime.so>+0xecfc7 torvalds#31 0x00002290f9906c66 in fit::function_impl<8UL, true, void(std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter>>, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte>>::operator()(const fit::function_impl<8UL, true, void (std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../sdk/lib/fit/include/lib/fit/function.h:315 <libdriver_runtime.so>+0xecc66 torvalds#32 0x00002290f98e73d9 in driver_runtime::Dispatcher::event_waiter::invoke_callback(driver_runtime::Dispatcher::event_waiter*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../src/devices/bin/driver_runtime/dispatcher.h:543 <libdriver_runtime.so>+0xcd3d9 torvalds#33 0x00002290f98e700d in driver_runtime::Dispatcher::event_waiter::handle_event(std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, async_dispatcher_t*, async::wait_base*, zx_status_t, zx_packet_signal_t const*) ../../src/devices/bin/driver_runtime/dispatcher.cc:1442 <libdriver_runtime.so>+0xcd00d torvalds#34 0x00002290f9918983 in async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>::handle_event(async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>*, async_dispatcher_t*, async::wait_base*, zx_status_t, zx_packet_signal_t const*) ../../src/devices/bin/driver_runtime/async_loop_owned_event_handler.h:59 <libdriver_runtime.so>+0xfe983 torvalds#35 0x00002290f9918b9e in async::wait_method<async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>, &async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>::handle_event>::call_handler(async_dispatcher_t*, async_wait_t*, zx_status_t, zx_packet_signal_t const*) ../../sdk/lib/async/include/lib/async/cpp/wait.h:201 <libdriver_runtime.so>+0xfeb9e torvalds#36 0x00002290f99bf509 in async_loop_dispatch_wait(async_loop_t*, async_wait_t*, zx_status_t, zx_packet_signal_t const*) ../../sdk/lib/async-loop/loop.c:394 <libdriver_runtime.so>+0x1a5509 torvalds#37 0x00002290f99b9958 in async_loop_run_once(async_loop_t*, zx_time_t) ../../sdk/lib/async-loop/loop.c:343 <libdriver_runtime.so>+0x19f958 torvalds#38 0x00002290f99b9247 in async_loop_run(async_loop_t*, zx_time_t, _Bool) ../../sdk/lib/async-loop/loop.c:301 <libdriver_runtime.so>+0x19f247 torvalds#39 0x00002290f99ba962 in async_loop_run_thread(void*) ../../sdk/lib/async-loop/loop.c:860 <libdriver_runtime.so>+0x1a0962 torvalds#40 0x000041afd176ef30 in start_c11(void*) ../../zircon/third_party/ulib/musl/pthread/pthread_create.c:63 <libc.so>+0x84f30 torvalds#41 0x000041afd18a448d in thread_trampoline(uintptr_t, uintptr_t) ../../zircon/system/ulib/runtime/thread.cc:100 <libc.so>+0x1ba48d Link: acpica/acpica@1c28da22 Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Link: https://patch.msgid.link/4664267.LvFx2qVVIh@rjwysocki.net Signed-off-by: Tamir Duberstein <tamird@gmail.com> [ rjw: Pick up the tag from Tamir ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
heftig
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Jun 27, 2025
Currently there is no ISB between __deactivate_cptr_traps() disabling traps that affect EL2 and fpsimd_lazy_switch_to_host() manipulating registers potentially affected by CPTR traps. When NV is not in use, this is safe because the relevant registers are only accessed when guest_owns_fp_regs() && vcpu_has_sve(vcpu), and this also implies that SVE traps affecting EL2 have been deactivated prior to __guest_entry(). When NV is in use, a guest hypervisor may have configured SVE traps for a nested context, and so it is necessary to have an ISB between __deactivate_cptr_traps() and fpsimd_lazy_switch_to_host(). Due to the current lack of an ISB, when a guest hypervisor enables SVE traps in CPTR, the host can take an unexpected SVE trap from within fpsimd_lazy_switch_to_host(), e.g. | Unhandled 64-bit el1h sync exception on CPU1, ESR 0x0000000066000000 -- SVE | CPU: 1 UID: 0 PID: 164 Comm: kvm-vcpu-0 Not tainted 6.15.0-rc4-00138-ga05e0f012c05 #3 PREEMPT | Hardware name: FVP Base RevC (DT) | pstate: 604023c9 (nZCv DAIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--) | pc : __kvm_vcpu_run+0x6f4/0x844 | lr : __kvm_vcpu_run+0x150/0x844 | sp : ffff800083903a60 | x29: ffff800083903a90 x28: ffff000801f4a300 x27: 0000000000000000 | x26: 0000000000000000 x25: ffff000801f90000 x24: ffff000801f900f0 | x23: ffff800081ff7720 x22: 0002433c807d623f x21: ffff000801f90000 | x20: ffff00087f730730 x19: 0000000000000000 x18: 0000000000000000 | x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 | x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000 | x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000 | x8 : 0000000000000000 x7 : 0000000000000000 x6 : ffff000801f90d70 | x5 : 0000000000001000 x4 : ffff8007fd739000 x3 : ffff000801f90000 | x2 : 0000000000000000 x1 : 00000000000003cc x0 : ffff800082f9d000 | Kernel panic - not syncing: Unhandled exception | CPU: 1 UID: 0 PID: 164 Comm: kvm-vcpu-0 Not tainted 6.15.0-rc4-00138-ga05e0f012c05 #3 PREEMPT | Hardware name: FVP Base RevC (DT) | Call trace: | show_stack+0x18/0x24 (C) | dump_stack_lvl+0x60/0x80 | dump_stack+0x18/0x24 | panic+0x168/0x360 | __panic_unhandled+0x68/0x74 | el1h_64_irq_handler+0x0/0x24 | el1h_64_sync+0x6c/0x70 | __kvm_vcpu_run+0x6f4/0x844 (P) | kvm_arm_vcpu_enter_exit+0x64/0xa0 | kvm_arch_vcpu_ioctl_run+0x21c/0x870 | kvm_vcpu_ioctl+0x1a8/0x9d0 | __arm64_sys_ioctl+0xb4/0xf4 | invoke_syscall+0x48/0x104 | el0_svc_common.constprop.0+0x40/0xe0 | do_el0_svc+0x1c/0x28 | el0_svc+0x30/0xcc | el0t_64_sync_handler+0x10c/0x138 | el0t_64_sync+0x198/0x19c | SMP: stopping secondary CPUs | Kernel Offset: disabled | CPU features: 0x0000,000002c0,02df4fb9,97ee773f | Memory Limit: none | ---[ end Kernel panic - not syncing: Unhandled exception ]--- Fix this by adding an ISB between __deactivate_traps() and fpsimd_lazy_switch_to_host(). Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Fuad Tabba <tabba@google.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Mark Brown <broonie@kernel.org> Cc: Oliver Upton <oliver.upton@linux.dev> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20250617133718.4014181-3-mark.rutland@arm.com Signed-off-by: Marc Zyngier <maz@kernel.org>
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…/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 fixes for 6.16, take #3 - Fix another set of FP/SIMD/SVE bugs affecting NV, and plugging some missing synchronisation - A small fix for the irqbypass hook fixes, tightening the check and ensuring that we only deal with MSI for both the old and the new route entry - Rework the way the shadow LRs are addressed in a nesting configuration, plugging an embarrassing bug as well as simplifying the whole process - Add yet another fix for the dreaded arch_timer_edge_cases selftest
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The issue arises when kzalloc() is invoked while holding umem_mutex or
any other lock acquired under umem_mutex. This is problematic because
kzalloc() can trigger fs_reclaim_aqcuire(), which may, in turn, invoke
mmu_notifier_invalidate_range_start(). This function can lead to
mlx5_ib_invalidate_range(), which attempts to acquire umem_mutex again,
resulting in a deadlock.
The problematic flow:
CPU0 | CPU1
---------------------------------------|------------------------------------------------
mlx5_ib_dereg_mr() |
→ revoke_mr() |
→ mutex_lock(&umem_odp->umem_mutex) |
| mlx5_mkey_cache_init()
| → mutex_lock(&dev->cache.rb_lock)
| → mlx5r_cache_create_ent_locked()
| → kzalloc(GFP_KERNEL)
| → fs_reclaim()
| → mmu_notifier_invalidate_range_start()
| → mlx5_ib_invalidate_range()
| → mutex_lock(&umem_odp->umem_mutex)
→ cache_ent_find_and_store() |
→ mutex_lock(&dev->cache.rb_lock) |
Additionally, when kzalloc() is called from within
cache_ent_find_and_store(), we encounter the same deadlock due to
re-acquisition of umem_mutex.
Solve by releasing umem_mutex in dereg_mr() after umr_revoke_mr()
and before acquiring rb_lock. This ensures that we don't hold
umem_mutex while performing memory allocations that could trigger
the reclaim path.
This change prevents the deadlock by ensuring proper lock ordering and
avoiding holding locks during memory allocation operations that could
trigger the reclaim path.
The following lockdep warning demonstrates the deadlock:
python3/20557 is trying to acquire lock:
ffff888387542128 (&umem_odp->umem_mutex){+.+.}-{4:4}, at:
mlx5_ib_invalidate_range+0x5b/0x550 [mlx5_ib]
but task is already holding lock:
ffffffff82f6b840 (mmu_notifier_invalidate_range_start){+.+.}-{0:0}, at:
unmap_vmas+0x7b/0x1a0
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #3 (mmu_notifier_invalidate_range_start){+.+.}-{0:0}:
fs_reclaim_acquire+0x60/0xd0
mem_cgroup_css_alloc+0x6f/0x9b0
cgroup_init_subsys+0xa4/0x240
cgroup_init+0x1c8/0x510
start_kernel+0x747/0x760
x86_64_start_reservations+0x25/0x30
x86_64_start_kernel+0x73/0x80
common_startup_64+0x129/0x138
-> #2 (fs_reclaim){+.+.}-{0:0}:
fs_reclaim_acquire+0x91/0xd0
__kmalloc_cache_noprof+0x4d/0x4c0
mlx5r_cache_create_ent_locked+0x75/0x620 [mlx5_ib]
mlx5_mkey_cache_init+0x186/0x360 [mlx5_ib]
mlx5_ib_stage_post_ib_reg_umr_init+0x3c/0x60 [mlx5_ib]
__mlx5_ib_add+0x4b/0x190 [mlx5_ib]
mlx5r_probe+0xd9/0x320 [mlx5_ib]
auxiliary_bus_probe+0x42/0x70
really_probe+0xdb/0x360
__driver_probe_device+0x8f/0x130
driver_probe_device+0x1f/0xb0
__driver_attach+0xd4/0x1f0
bus_for_each_dev+0x79/0xd0
bus_add_driver+0xf0/0x200
driver_register+0x6e/0xc0
__auxiliary_driver_register+0x6a/0xc0
do_one_initcall+0x5e/0x390
do_init_module+0x88/0x240
init_module_from_file+0x85/0xc0
idempotent_init_module+0x104/0x300
__x64_sys_finit_module+0x68/0xc0
do_syscall_64+0x6d/0x140
entry_SYSCALL_64_after_hwframe+0x4b/0x53
-> #1 (&dev->cache.rb_lock){+.+.}-{4:4}:
__mutex_lock+0x98/0xf10
__mlx5_ib_dereg_mr+0x6f2/0x890 [mlx5_ib]
mlx5_ib_dereg_mr+0x21/0x110 [mlx5_ib]
ib_dereg_mr_user+0x85/0x1f0 [ib_core]
uverbs_free_mr+0x19/0x30 [ib_uverbs]
destroy_hw_idr_uobject+0x21/0x80 [ib_uverbs]
uverbs_destroy_uobject+0x60/0x3d0 [ib_uverbs]
uobj_destroy+0x57/0xa0 [ib_uverbs]
ib_uverbs_cmd_verbs+0x4d5/0x1210 [ib_uverbs]
ib_uverbs_ioctl+0x129/0x230 [ib_uverbs]
__x64_sys_ioctl+0x596/0xaa0
do_syscall_64+0x6d/0x140
entry_SYSCALL_64_after_hwframe+0x4b/0x53
-> #0 (&umem_odp->umem_mutex){+.+.}-{4:4}:
__lock_acquire+0x1826/0x2f00
lock_acquire+0xd3/0x2e0
__mutex_lock+0x98/0xf10
mlx5_ib_invalidate_range+0x5b/0x550 [mlx5_ib]
__mmu_notifier_invalidate_range_start+0x18e/0x1f0
unmap_vmas+0x182/0x1a0
exit_mmap+0xf3/0x4a0
mmput+0x3a/0x100
do_exit+0x2b9/0xa90
do_group_exit+0x32/0xa0
get_signal+0xc32/0xcb0
arch_do_signal_or_restart+0x29/0x1d0
syscall_exit_to_user_mode+0x105/0x1d0
do_syscall_64+0x79/0x140
entry_SYSCALL_64_after_hwframe+0x4b/0x53
Chain exists of:
&dev->cache.rb_lock --> mmu_notifier_invalidate_range_start -->
&umem_odp->umem_mutex
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&umem_odp->umem_mutex);
lock(mmu_notifier_invalidate_range_start);
lock(&umem_odp->umem_mutex);
lock(&dev->cache.rb_lock);
*** DEADLOCK ***
Fixes: abb604a ("RDMA/mlx5: Fix a race for an ODP MR which leads to CQE with error")
Signed-off-by: Or Har-Toov <ohartoov@nvidia.com>
Reviewed-by: Michael Guralnik <michaelgur@nvidia.com>
Link: https://patch.msgid.link/3c8f225a8a9fade647d19b014df1172544643e4a.1750061612.git.leon@kernel.org
Signed-off-by: Leon Romanovsky <leon@kernel.org>
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[ Upstream commit 2ed25aa ] The issue arises when kzalloc() is invoked while holding umem_mutex or any other lock acquired under umem_mutex. This is problematic because kzalloc() can trigger fs_reclaim_aqcuire(), which may, in turn, invoke mmu_notifier_invalidate_range_start(). This function can lead to mlx5_ib_invalidate_range(), which attempts to acquire umem_mutex again, resulting in a deadlock. The problematic flow: CPU0 | CPU1 ---------------------------------------|------------------------------------------------ mlx5_ib_dereg_mr() | → revoke_mr() | → mutex_lock(&umem_odp->umem_mutex) | | mlx5_mkey_cache_init() | → mutex_lock(&dev->cache.rb_lock) | → mlx5r_cache_create_ent_locked() | → kzalloc(GFP_KERNEL) | → fs_reclaim() | → mmu_notifier_invalidate_range_start() | → mlx5_ib_invalidate_range() | → mutex_lock(&umem_odp->umem_mutex) → cache_ent_find_and_store() | → mutex_lock(&dev->cache.rb_lock) | Additionally, when kzalloc() is called from within cache_ent_find_and_store(), we encounter the same deadlock due to re-acquisition of umem_mutex. Solve by releasing umem_mutex in dereg_mr() after umr_revoke_mr() and before acquiring rb_lock. This ensures that we don't hold umem_mutex while performing memory allocations that could trigger the reclaim path. This change prevents the deadlock by ensuring proper lock ordering and avoiding holding locks during memory allocation operations that could trigger the reclaim path. The following lockdep warning demonstrates the deadlock: python3/20557 is trying to acquire lock: ffff888387542128 (&umem_odp->umem_mutex){+.+.}-{4:4}, at: mlx5_ib_invalidate_range+0x5b/0x550 [mlx5_ib] but task is already holding lock: ffffffff82f6b840 (mmu_notifier_invalidate_range_start){+.+.}-{0:0}, at: unmap_vmas+0x7b/0x1a0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (mmu_notifier_invalidate_range_start){+.+.}-{0:0}: fs_reclaim_acquire+0x60/0xd0 mem_cgroup_css_alloc+0x6f/0x9b0 cgroup_init_subsys+0xa4/0x240 cgroup_init+0x1c8/0x510 start_kernel+0x747/0x760 x86_64_start_reservations+0x25/0x30 x86_64_start_kernel+0x73/0x80 common_startup_64+0x129/0x138 -> #2 (fs_reclaim){+.+.}-{0:0}: fs_reclaim_acquire+0x91/0xd0 __kmalloc_cache_noprof+0x4d/0x4c0 mlx5r_cache_create_ent_locked+0x75/0x620 [mlx5_ib] mlx5_mkey_cache_init+0x186/0x360 [mlx5_ib] mlx5_ib_stage_post_ib_reg_umr_init+0x3c/0x60 [mlx5_ib] __mlx5_ib_add+0x4b/0x190 [mlx5_ib] mlx5r_probe+0xd9/0x320 [mlx5_ib] auxiliary_bus_probe+0x42/0x70 really_probe+0xdb/0x360 __driver_probe_device+0x8f/0x130 driver_probe_device+0x1f/0xb0 __driver_attach+0xd4/0x1f0 bus_for_each_dev+0x79/0xd0 bus_add_driver+0xf0/0x200 driver_register+0x6e/0xc0 __auxiliary_driver_register+0x6a/0xc0 do_one_initcall+0x5e/0x390 do_init_module+0x88/0x240 init_module_from_file+0x85/0xc0 idempotent_init_module+0x104/0x300 __x64_sys_finit_module+0x68/0xc0 do_syscall_64+0x6d/0x140 entry_SYSCALL_64_after_hwframe+0x4b/0x53 -> #1 (&dev->cache.rb_lock){+.+.}-{4:4}: __mutex_lock+0x98/0xf10 __mlx5_ib_dereg_mr+0x6f2/0x890 [mlx5_ib] mlx5_ib_dereg_mr+0x21/0x110 [mlx5_ib] ib_dereg_mr_user+0x85/0x1f0 [ib_core] uverbs_free_mr+0x19/0x30 [ib_uverbs] destroy_hw_idr_uobject+0x21/0x80 [ib_uverbs] uverbs_destroy_uobject+0x60/0x3d0 [ib_uverbs] uobj_destroy+0x57/0xa0 [ib_uverbs] ib_uverbs_cmd_verbs+0x4d5/0x1210 [ib_uverbs] ib_uverbs_ioctl+0x129/0x230 [ib_uverbs] __x64_sys_ioctl+0x596/0xaa0 do_syscall_64+0x6d/0x140 entry_SYSCALL_64_after_hwframe+0x4b/0x53 -> #0 (&umem_odp->umem_mutex){+.+.}-{4:4}: __lock_acquire+0x1826/0x2f00 lock_acquire+0xd3/0x2e0 __mutex_lock+0x98/0xf10 mlx5_ib_invalidate_range+0x5b/0x550 [mlx5_ib] __mmu_notifier_invalidate_range_start+0x18e/0x1f0 unmap_vmas+0x182/0x1a0 exit_mmap+0xf3/0x4a0 mmput+0x3a/0x100 do_exit+0x2b9/0xa90 do_group_exit+0x32/0xa0 get_signal+0xc32/0xcb0 arch_do_signal_or_restart+0x29/0x1d0 syscall_exit_to_user_mode+0x105/0x1d0 do_syscall_64+0x79/0x140 entry_SYSCALL_64_after_hwframe+0x4b/0x53 Chain exists of: &dev->cache.rb_lock --> mmu_notifier_invalidate_range_start --> &umem_odp->umem_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&umem_odp->umem_mutex); lock(mmu_notifier_invalidate_range_start); lock(&umem_odp->umem_mutex); lock(&dev->cache.rb_lock); *** DEADLOCK *** Fixes: abb604a ("RDMA/mlx5: Fix a race for an ODP MR which leads to CQE with error") Signed-off-by: Or Har-Toov <ohartoov@nvidia.com> Reviewed-by: Michael Guralnik <michaelgur@nvidia.com> Link: https://patch.msgid.link/3c8f225a8a9fade647d19b014df1172544643e4a.1750061612.git.leon@kernel.org Signed-off-by: Leon Romanovsky <leon@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
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When operating in concurrent STA/AP mode with host MLME enabled, the firmware incorrectly sends disassociation frames to the STA interface when clients disconnect from the AP interface. This causes kernel warnings as the STA interface processes disconnect events that don't apply to it: [ 1303.240540] WARNING: CPU: 0 PID: 513 at net/wireless/mlme.c:141 cfg80211_process_disassoc+0x78/0xec [cfg80211] [ 1303.250861] Modules linked in: 8021q garp stp mrp llc rfcomm bnep btnxpuart nls_iso8859_1 nls_cp437 onboard_us [ 1303.327651] CPU: 0 UID: 0 PID: 513 Comm: kworker/u9:2 Not tainted 6.16.0-rc1+ #3 PREEMPT [ 1303.335937] Hardware name: Toradex Verdin AM62 WB on Verdin Development Board (DT) [ 1303.343588] Workqueue: MWIFIEX_RX_WORK_QUEUE mwifiex_rx_work_queue [mwifiex] [ 1303.350856] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 1303.357904] pc : cfg80211_process_disassoc+0x78/0xec [cfg80211] [ 1303.364065] lr : cfg80211_process_disassoc+0x70/0xec [cfg80211] [ 1303.370221] sp : ffff800083053be0 [ 1303.373590] x29: ffff800083053be0 x28: 0000000000000000 x27: 0000000000000000 [ 1303.380855] x26: 0000000000000000 x25: 00000000ffffffff x24: ffff000002c5b8ae [ 1303.388120] x23: ffff000002c5b884 x22: 0000000000000001 x21: 0000000000000008 [ 1303.395382] x20: ffff000002c5b8ae x19: ffff0000064dd408 x18: 0000000000000006 [ 1303.402646] x17: 3a36333a61623a30 x16: 32206d6f72662063 x15: ffff800080bfe048 [ 1303.409910] x14: ffff000003625300 x13: 0000000000000001 x12: 0000000000000000 [ 1303.417173] x11: 0000000000000002 x10: ffff000003958600 x9 : ffff000003625300 [ 1303.424434] x8 : ffff00003fd9ef40 x7 : ffff0000039fc280 x6 : 0000000000000002 [ 1303.431695] x5 : ffff0000038976d4 x4 : 0000000000000000 x3 : 0000000000003186 [ 1303.438956] x2 : 000000004836ba20 x1 : 0000000000006986 x0 : 00000000d00479de [ 1303.446221] Call trace: [ 1303.448722] cfg80211_process_disassoc+0x78/0xec [cfg80211] (P) [ 1303.454894] cfg80211_rx_mlme_mgmt+0x64/0xf8 [cfg80211] [ 1303.460362] mwifiex_process_mgmt_packet+0x1ec/0x460 [mwifiex] [ 1303.466380] mwifiex_process_sta_rx_packet+0x1bc/0x2a0 [mwifiex] [ 1303.472573] mwifiex_handle_rx_packet+0xb4/0x13c [mwifiex] [ 1303.478243] mwifiex_rx_work_queue+0x158/0x198 [mwifiex] [ 1303.483734] process_one_work+0x14c/0x28c [ 1303.487845] worker_thread+0x2cc/0x3d4 [ 1303.491680] kthread+0x12c/0x208 [ 1303.495014] ret_from_fork+0x10/0x20 Add validation in the STA receive path to verify that disassoc/deauth frames originate from the connected AP. Frames that fail this check are discarded early, preventing them from reaching the MLME layer and triggering WARN_ON(). This filtering logic is similar with that used in the ieee80211_rx_mgmt_disassoc() function in mac80211, which drops disassoc frames that don't match the current BSSID (!ether_addr_equal(mgmt->bssid, sdata->vif.cfg.ap_addr)), ensuring only relevant frames are processed. Tested on: - 8997 with FW 16.68.1.p197 Fixes: 3699589 ("wifi: mwifiex: add host mlme for client mode") Cc: stable@vger.kernel.org Signed-off-by: Vitor Soares <vitor.soares@toradex.com> Reviewed-by: Jeff Chen <jeff.chen_1@nxp.con> Reviewed-by: Francesco Dolcini <francesco.dolcini@toradex.com> Link: https://patch.msgid.link/20250701142643.658990-1-ivitro@gmail.com Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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alloc_tag_top_users() attempts to lock alloc_tag_cttype->mod_lock even
when the alloc_tag_cttype is not allocated because:
1) alloc tagging is disabled because mem profiling is disabled
(!alloc_tag_cttype)
2) alloc tagging is enabled, but not yet initialized (!alloc_tag_cttype)
3) alloc tagging is enabled, but failed initialization
(!alloc_tag_cttype or IS_ERR(alloc_tag_cttype))
In all cases, alloc_tag_cttype is not allocated, and therefore
alloc_tag_top_users() should not attempt to acquire the semaphore.
This leads to a crash on memory allocation failure by attempting to
acquire a non-existent semaphore:
Oops: general protection fault, probably for non-canonical address 0xdffffc000000001b: 0000 [#3] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x00000000000000d8-0x00000000000000df]
CPU: 2 UID: 0 PID: 1 Comm: systemd Tainted: G D 6.16.0-rc2 #1 VOLUNTARY
Tainted: [D]=DIE
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:down_read_trylock+0xaa/0x3b0
Code: d0 7c 08 84 d2 0f 85 a0 02 00 00 8b 0d df 31 dd 04 85 c9 75 29 48 b8 00 00 00 00 00 fc ff df 48 8d 6b 68 48 89 ea 48 c1 ea 03 <80> 3c 02 00 0f 85 88 02 00 00 48 3b 5b 68 0f 85 53 01 00 00 65 ff
RSP: 0000:ffff8881002ce9b8 EFLAGS: 00010016
RAX: dffffc0000000000 RBX: 0000000000000070 RCX: 0000000000000000
RDX: 000000000000001b RSI: 000000000000000a RDI: 0000000000000070
RBP: 00000000000000d8 R08: 0000000000000001 R09: ffffed107dde49d1
R10: ffff8883eef24e8b R11: ffff8881002cec20 R12: 1ffff11020059d37
R13: 00000000003fff7b R14: ffff8881002cec20 R15: dffffc0000000000
FS: 00007f963f21d940(0000) GS:ffff888458ca6000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f963f5edf71 CR3: 000000010672c000 CR4: 0000000000350ef0
Call Trace:
<TASK>
codetag_trylock_module_list+0xd/0x20
alloc_tag_top_users+0x369/0x4b0
__show_mem+0x1cd/0x6e0
warn_alloc+0x2b1/0x390
__alloc_frozen_pages_noprof+0x12b9/0x21a0
alloc_pages_mpol+0x135/0x3e0
alloc_slab_page+0x82/0xe0
new_slab+0x212/0x240
___slab_alloc+0x82a/0xe00
</TASK>
As David Wang points out, this issue became easier to trigger after commit
780138b ("alloc_tag: check mem_profiling_support in alloc_tag_init").
Before the commit, the issue occurred only when it failed to allocate and
initialize alloc_tag_cttype or if a memory allocation fails before
alloc_tag_init() is called. After the commit, it can be easily triggered
when memory profiling is compiled but disabled at boot.
To properly determine whether alloc_tag_init() has been called and its
data structures initialized, verify that alloc_tag_cttype is a valid
pointer before acquiring the semaphore. If the variable is NULL or an
error value, it has not been properly initialized. In such a case, just
skip and do not attempt to acquire the semaphore.
[harry.yoo@oracle.com: v3]
Link: https://lkml.kernel.org/r/20250624072513.84219-1-harry.yoo@oracle.com
Link: https://lkml.kernel.org/r/20250620195305.1115151-1-harry.yoo@oracle.com
Fixes: 780138b ("alloc_tag: check mem_profiling_support in alloc_tag_init")
Fixes: 1438d34 ("lib: add memory allocations report in show_mem()")
Signed-off-by: Harry Yoo <harry.yoo@oracle.com>
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202506181351.bba867dd-lkp@intel.com
Acked-by: Suren Baghdasaryan <surenb@google.com>
Tested-by: Raghavendra K T <raghavendra.kt@amd.com>
Cc: Casey Chen <cachen@purestorage.com>
Cc: David Wang <00107082@163.com>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Yuanyuan Zhong <yzhong@purestorage.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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If "try_verify_in_tasklet" is set for dm-verity, DM_BUFIO_CLIENT_NO_SLEEP
is enabled for dm-bufio. However, when bufio tries to evict buffers, there
is a chance to trigger scheduling in spin_lock_bh, the following warning
is hit:
BUG: sleeping function called from invalid context at drivers/md/dm-bufio.c:2745
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 123, name: kworker/2:2
preempt_count: 201, expected: 0
RCU nest depth: 0, expected: 0
4 locks held by kworker/2:2/123:
#0: ffff88800a2d1548 ((wq_completion)dm_bufio_cache){....}-{0:0}, at: process_one_work+0xe46/0x1970
#1: ffffc90000d97d20 ((work_completion)(&dm_bufio_replacement_work)){....}-{0:0}, at: process_one_work+0x763/0x1970
#2: ffffffff8555b528 (dm_bufio_clients_lock){....}-{3:3}, at: do_global_cleanup+0x1ce/0x710
#3: ffff88801d5820b8 (&c->spinlock){....}-{2:2}, at: do_global_cleanup+0x2a5/0x710
Preemption disabled at:
[<0000000000000000>] 0x0
CPU: 2 UID: 0 PID: 123 Comm: kworker/2:2 Not tainted 6.16.0-rc3-g90548c634bd0 torvalds#305 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
Workqueue: dm_bufio_cache do_global_cleanup
Call Trace:
<TASK>
dump_stack_lvl+0x53/0x70
__might_resched+0x360/0x4e0
do_global_cleanup+0x2f5/0x710
process_one_work+0x7db/0x1970
worker_thread+0x518/0xea0
kthread+0x359/0x690
ret_from_fork+0xf3/0x1b0
ret_from_fork_asm+0x1a/0x30
</TASK>
That can be reproduced by:
veritysetup format --data-block-size=4096 --hash-block-size=4096 /dev/vda /dev/vdb
SIZE=$(blockdev --getsz /dev/vda)
dmsetup create myverity -r --table "0 $SIZE verity 1 /dev/vda /dev/vdb 4096 4096 <data_blocks> 1 sha256 <root_hash> <salt> 1 try_verify_in_tasklet"
mount /dev/dm-0 /mnt -o ro
echo 102400 > /sys/module/dm_bufio/parameters/max_cache_size_bytes
[read files in /mnt]
Cc: stable@vger.kernel.org # v6.4+
Fixes: 450e8de ("dm bufio: improve concurrent IO performance")
Signed-off-by: Wang Shuai <wangshuai12@xiaomi.com>
Signed-off-by: Sheng Yong <shengyong1@xiaomi.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
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If the PHY driver uses another PHY internally (e.g. in case of eUSB2,
repeaters are represented as PHYs), then it would trigger the following
lockdep splat because all PHYs use a single static lockdep key and thus
lockdep can not identify whether there is a dependency or not and
reports a false positive.
Make PHY subsystem use dynamic lockdep keys, assigning each driver a
separate key. This way lockdep can correctly identify dependency graph
between mutexes.
============================================
WARNING: possible recursive locking detected
6.15.0-rc7-next-20250522-12896-g3932f283970c #3455 Not tainted
--------------------------------------------
kworker/u51:0/78 is trying to acquire lock:
ffff0008116554f0 (&phy->mutex){+.+.}-{4:4}, at: phy_init+0x4c/0x12c
but task is already holding lock:
ffff000813c10cf0 (&phy->mutex){+.+.}-{4:4}, at: phy_init+0x4c/0x12c
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&phy->mutex);
lock(&phy->mutex);
*** DEADLOCK ***
May be due to missing lock nesting notation
4 locks held by kworker/u51:0/78:
#0: ffff000800010948 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x18c/0x5ec
#1: ffff80008036bdb0 (deferred_probe_work){+.+.}-{0:0}, at: process_one_work+0x1b4/0x5ec
#2: ffff0008094ac8f8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x38/0x188
#3: ffff000813c10cf0 (&phy->mutex){+.+.}-{4:4}, at: phy_init+0x4c/0x12c
stack backtrace:
CPU: 0 UID: 0 PID: 78 Comm: kworker/u51:0 Not tainted 6.15.0-rc7-next-20250522-12896-g3932f283970c #3455 PREEMPT
Hardware name: Qualcomm CRD, BIOS 6.0.240904.BOOT.MXF.2.4-00528.1-HAMOA-1 09/ 4/2024
Workqueue: events_unbound deferred_probe_work_func
Call trace:
show_stack+0x18/0x24 (C)
dump_stack_lvl+0x90/0xd0
dump_stack+0x18/0x24
print_deadlock_bug+0x258/0x348
__lock_acquire+0x10fc/0x1f84
lock_acquire+0x1c8/0x338
__mutex_lock+0xb8/0x59c
mutex_lock_nested+0x24/0x30
phy_init+0x4c/0x12c
snps_eusb2_hsphy_init+0x54/0x1a0
phy_init+0xe0/0x12c
dwc3_core_init+0x450/0x10b4
dwc3_core_probe+0xce4/0x15fc
dwc3_probe+0x64/0xb0
platform_probe+0x68/0xc4
really_probe+0xbc/0x298
__driver_probe_device+0x78/0x12c
driver_probe_device+0x3c/0x160
__device_attach_driver+0xb8/0x138
bus_for_each_drv+0x84/0xe0
__device_attach+0x9c/0x188
device_initial_probe+0x14/0x20
bus_probe_device+0xac/0xb0
deferred_probe_work_func+0x8c/0xc8
process_one_work+0x208/0x5ec
worker_thread+0x1c0/0x368
kthread+0x14c/0x20c
ret_from_fork+0x10/0x20
Fixes: 3584f63 ("phy: qcom: phy-qcom-snps-eusb2: Add support for eUSB2 repeater")
Fixes: e246355 ("phy: amlogic: Add Amlogic AXG PCIE PHY Driver")
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Reviewed-by: Abel Vesa <abel.vesa@linaro.org>
Reported-by: Johan Hovold <johan+linaro@kernel.org>
Link: https://lore.kernel.org/lkml/ZnpoAVGJMG4Zu-Jw@hovoldconsulting.com/
Reviewed-by: Johan Hovold <johan+linaro@kernel.org>
Tested-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20250605-phy-subinit-v3-1-1e1e849e10cd@oss.qualcomm.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
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The AARP proxy‐probe routine (aarp_proxy_probe_network) sends a probe,
releases the aarp_lock, sleeps, then re-acquires the lock. During that
window an expire timer thread (__aarp_expire_timer) can remove and
kfree() the same entry, leading to a use-after-free.
race condition:
cpu 0 | cpu 1
atalk_sendmsg() | atif_proxy_probe_device()
aarp_send_ddp() | aarp_proxy_probe_network()
mod_timer() | lock(aarp_lock) // LOCK!!
timeout around 200ms | alloc(aarp_entry)
and then call | proxies[hash] = aarp_entry
aarp_expire_timeout() | aarp_send_probe()
| unlock(aarp_lock) // UNLOCK!!
lock(aarp_lock) // LOCK!! | msleep(100);
__aarp_expire_timer(&proxies[ct]) |
free(aarp_entry) |
unlock(aarp_lock) // UNLOCK!! |
| lock(aarp_lock) // LOCK!!
| UAF aarp_entry !!
==================================================================
BUG: KASAN: slab-use-after-free in aarp_proxy_probe_network+0x560/0x630 net/appletalk/aarp.c:493
Read of size 4 at addr ffff8880123aa360 by task repro/13278
CPU: 3 UID: 0 PID: 13278 Comm: repro Not tainted 6.15.2 #3 PREEMPT(full)
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1b0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:408 [inline]
print_report+0xc1/0x630 mm/kasan/report.c:521
kasan_report+0xca/0x100 mm/kasan/report.c:634
aarp_proxy_probe_network+0x560/0x630 net/appletalk/aarp.c:493
atif_proxy_probe_device net/appletalk/ddp.c:332 [inline]
atif_ioctl+0xb58/0x16c0 net/appletalk/ddp.c:857
atalk_ioctl+0x198/0x2f0 net/appletalk/ddp.c:1818
sock_do_ioctl+0xdc/0x260 net/socket.c:1190
sock_ioctl+0x239/0x6a0 net/socket.c:1311
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:906 [inline]
__se_sys_ioctl fs/ioctl.c:892 [inline]
__x64_sys_ioctl+0x194/0x200 fs/ioctl.c:892
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcb/0x250 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
</TASK>
Allocated:
aarp_alloc net/appletalk/aarp.c:382 [inline]
aarp_proxy_probe_network+0xd8/0x630 net/appletalk/aarp.c:468
atif_proxy_probe_device net/appletalk/ddp.c:332 [inline]
atif_ioctl+0xb58/0x16c0 net/appletalk/ddp.c:857
atalk_ioctl+0x198/0x2f0 net/appletalk/ddp.c:1818
Freed:
kfree+0x148/0x4d0 mm/slub.c:4841
__aarp_expire net/appletalk/aarp.c:90 [inline]
__aarp_expire_timer net/appletalk/aarp.c:261 [inline]
aarp_expire_timeout+0x480/0x6e0 net/appletalk/aarp.c:317
The buggy address belongs to the object at ffff8880123aa300
which belongs to the cache kmalloc-192 of size 192
The buggy address is located 96 bytes inside of
freed 192-byte region [ffff8880123aa300, ffff8880123aa3c0)
Memory state around the buggy address:
ffff8880123aa200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff8880123aa280: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880123aa300: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880123aa380: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
ffff8880123aa400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kito Xu (veritas501) <hxzene@gmail.com>
Link: https://patch.msgid.link/20250717012843.880423-1-hxzene@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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pert script tests fails with segmentation fault as below:
92: perf script tests:
--- start ---
test child forked, pid 103769
DB test
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.012 MB /tmp/perf-test-script.7rbftEpOzX/perf.data (9 samples) ]
/usr/libexec/perf-core/tests/shell/script.sh: line 35:
103780 Segmentation fault (core dumped)
perf script -i "${perfdatafile}" -s "${db_test}"
--- Cleaning up ---
---- end(-1) ----
92: perf script tests : FAILED!
Backtrace pointed to :
#0 0x0000000010247dd0 in maps.machine ()
#1 0x00000000101d178c in db_export.sample ()
#2 0x00000000103412c8 in python_process_event ()
#3 0x000000001004eb28 in process_sample_event ()
#4 0x000000001024fcd0 in machines.deliver_event ()
#5 0x000000001025005c in perf_session.deliver_event ()
#6 0x00000000102568b0 in __ordered_events__flush.part.0 ()
#7 0x0000000010251618 in perf_session.process_events ()
#8 0x0000000010053620 in cmd_script ()
#9 0x00000000100b5a28 in run_builtin ()
torvalds#10 0x00000000100b5f94 in handle_internal_command ()
torvalds#11 0x0000000010011114 in main ()
Further investigation reveals that this occurs in the `perf script tests`,
because it uses `db_test.py` script. This script sets `perf_db_export_mode = True`.
With `perf_db_export_mode` enabled, if a sample originates from a hypervisor,
perf doesn't set maps for "[H]" sample in the code. Consequently, `al->maps` remains NULL
when `maps__machine(al->maps)` is called from `db_export__sample`.
As al->maps can be NULL in case of Hypervisor samples , use thread->maps
because even for Hypervisor sample, machine should exist.
If we don't have machine for some reason, return -1 to avoid segmentation fault.
Reported-by: Disha Goel <disgoel@linux.ibm.com>
Signed-off-by: Aditya Bodkhe <aditya.b1@linux.ibm.com>
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Disha Goel <disgoel@linux.ibm.com>
Link: https://lore.kernel.org/r/20250429065132.36839-1-adityab1@linux.ibm.com
Suggested-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
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Without the change `perf `hangs up on charaster devices. On my system
it's enough to run system-wide sampler for a few seconds to get the
hangup:
$ perf record -a -g --call-graph=dwarf
$ perf report
# hung
`strace` shows that hangup happens on reading on a character device
`/dev/dri/renderD128`
$ strace -y -f -p 2780484
strace: Process 2780484 attached
pread64(101</dev/dri/renderD128>, strace: Process 2780484 detached
It's call trace descends into `elfutils`:
$ gdb -p 2780484
(gdb) bt
#0 0x00007f5e508f04b7 in __libc_pread64 (fd=101, buf=0x7fff9df7edb0, count=0, offset=0)
at ../sysdeps/unix/sysv/linux/pread64.c:25
#1 0x00007f5e52b79515 in read_file () from /<<NIX>>/elfutils-0.192/lib/libelf.so.1
#2 0x00007f5e52b25666 in libdw_open_elf () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1
#3 0x00007f5e52b25907 in __libdw_open_file () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1
#4 0x00007f5e52b120a9 in dwfl_report_elf@@ELFUTILS_0.156 ()
from /<<NIX>>/elfutils-0.192/lib/libdw.so.1
#5 0x000000000068bf20 in __report_module (al=al@entry=0x7fff9df80010, ip=ip@entry=139803237033216, ui=ui@entry=0x5369b5e0)
at util/dso.h:537
#6 0x000000000068c3d1 in report_module (ip=139803237033216, ui=0x5369b5e0) at util/unwind-libdw.c:114
#7 frame_callback (state=0x535aef10, arg=0x5369b5e0) at util/unwind-libdw.c:242
#8 0x00007f5e52b261d3 in dwfl_thread_getframes () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1
#9 0x00007f5e52b25bdb in get_one_thread_cb () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1
torvalds#10 0x00007f5e52b25faa in dwfl_getthreads () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1
torvalds#11 0x00007f5e52b26514 in dwfl_getthread_frames () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1
torvalds#12 0x000000000068c6ce in unwind__get_entries (cb=cb@entry=0x5d4620 <unwind_entry>, arg=arg@entry=0x10cd5fa0,
thread=thread@entry=0x1076a290, data=data@entry=0x7fff9df80540, max_stack=max_stack@entry=127,
best_effort=best_effort@entry=false) at util/thread.h:152
torvalds#13 0x00000000005dae95 in thread__resolve_callchain_unwind (evsel=0x106006d0, thread=0x1076a290, cursor=0x10cd5fa0,
sample=0x7fff9df80540, max_stack=127, symbols=true) at util/machine.c:2939
torvalds#14 thread__resolve_callchain_unwind (thread=0x1076a290, cursor=0x10cd5fa0, evsel=0x106006d0, sample=0x7fff9df80540,
max_stack=127, symbols=true) at util/machine.c:2920
torvalds#15 __thread__resolve_callchain (thread=0x1076a290, cursor=0x10cd5fa0, evsel=0x106006d0, evsel@entry=0x7fff9df80440,
sample=0x7fff9df80540, parent=parent@entry=0x7fff9df804a0, root_al=root_al@entry=0x7fff9df80440, max_stack=127, symbols=true)
at util/machine.c:2970
torvalds#16 0x00000000005d0cb2 in thread__resolve_callchain (thread=<optimized out>, cursor=<optimized out>, evsel=0x7fff9df80440,
sample=<optimized out>, parent=0x7fff9df804a0, root_al=0x7fff9df80440, max_stack=127) at util/machine.h:198
torvalds#17 sample__resolve_callchain (sample=<optimized out>, cursor=<optimized out>, parent=parent@entry=0x7fff9df804a0,
evsel=evsel@entry=0x106006d0, al=al@entry=0x7fff9df80440, max_stack=max_stack@entry=127) at util/callchain.c:1127
torvalds#18 0x0000000000617e08 in hist_entry_iter__add (iter=iter@entry=0x7fff9df80480, al=al@entry=0x7fff9df80440, max_stack_depth=127,
arg=arg@entry=0x7fff9df81ae0) at util/hist.c:1255
torvalds#19 0x000000000045d2d0 in process_sample_event (tool=0x7fff9df81ae0, event=<optimized out>, sample=0x7fff9df80540,
evsel=0x106006d0, machine=<optimized out>) at builtin-report.c:334
torvalds#20 0x00000000005e3bb1 in perf_session__deliver_event (session=0x105ff2c0, event=0x7f5c7d735ca0, tool=0x7fff9df81ae0,
file_offset=2914716832, file_path=0x105ffbf0 "perf.data") at util/session.c:1367
torvalds#21 0x00000000005e8d93 in do_flush (oe=0x105ffa50, show_progress=false) at util/ordered-events.c:245
torvalds#22 __ordered_events__flush (oe=0x105ffa50, how=OE_FLUSH__ROUND, timestamp=<optimized out>) at util/ordered-events.c:324
torvalds#23 0x00000000005e1f64 in perf_session__process_user_event (session=0x105ff2c0, event=0x7f5c7d752b18, file_offset=2914835224,
file_path=0x105ffbf0 "perf.data") at util/session.c:1419
torvalds#24 0x00000000005e47c7 in reader__read_event (rd=rd@entry=0x7fff9df81260, session=session@entry=0x105ff2c0,
--Type <RET> for more, q to quit, c to continue without paging--
quit
prog=prog@entry=0x7fff9df81220) at util/session.c:2132
torvalds#25 0x00000000005e4b37 in reader__process_events (rd=0x7fff9df81260, session=0x105ff2c0, prog=0x7fff9df81220)
at util/session.c:2181
torvalds#26 __perf_session__process_events (session=0x105ff2c0) at util/session.c:2226
torvalds#27 perf_session__process_events (session=session@entry=0x105ff2c0) at util/session.c:2390
torvalds#28 0x0000000000460add in __cmd_report (rep=0x7fff9df81ae0) at builtin-report.c:1076
torvalds#29 cmd_report (argc=<optimized out>, argv=<optimized out>) at builtin-report.c:1827
torvalds#30 0x00000000004c5a40 in run_builtin (p=p@entry=0xd8f7f8 <commands+312>, argc=argc@entry=1, argv=argv@entry=0x7fff9df844b0)
at perf.c:351
torvalds#31 0x00000000004c5d63 in handle_internal_command (argc=argc@entry=1, argv=argv@entry=0x7fff9df844b0) at perf.c:404
torvalds#32 0x0000000000442de3 in run_argv (argcp=<synthetic pointer>, argv=<synthetic pointer>) at perf.c:448
torvalds#33 main (argc=<optimized out>, argv=0x7fff9df844b0) at perf.c:556
The hangup happens because nothing in` perf` or `elfutils` checks if a
mapped file is easily readable.
The change conservatively skips all non-regular files.
Signed-off-by: Sergei Trofimovich <slyich@gmail.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20250505174419.2814857-1-slyich@gmail.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
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Symbolize stack traces by creating a live machine. Add this
functionality to dump_stack and switch dump_stack users to use
it. Switch TUI to use it. Add stack traces to the child test function
which can be useful to diagnose blocked code.
Example output:
```
$ perf test -vv PERF_RECORD_
...
7: PERF_RECORD_* events & perf_sample fields:
7: PERF_RECORD_* events & perf_sample fields : Running (1 active)
^C
Signal (2) while running tests.
Terminating tests with the same signal
Internal test harness failure. Completing any started tests:
: 7: PERF_RECORD_* events & perf_sample fields:
---- unexpected signal (2) ----
#0 0x55788c6210a3 in child_test_sig_handler builtin-test.c:0
#1 0x7fc12fe49df0 in __restore_rt libc_sigaction.c:0
#2 0x7fc12fe99687 in __internal_syscall_cancel cancellation.c:64
#3 0x7fc12fee5f7a in clock_nanosleep@GLIBC_2.2.5 clock_nanosleep.c:72
#4 0x7fc12fef1393 in __nanosleep nanosleep.c:26
#5 0x7fc12ff02d68 in __sleep sleep.c:55
#6 0x55788c63196b in test__PERF_RECORD perf-record.c:0
#7 0x55788c620fb0 in run_test_child builtin-test.c:0
#8 0x55788c5bd18d in start_command run-command.c:127
#9 0x55788c621ef3 in __cmd_test builtin-test.c:0
torvalds#10 0x55788c6225bf in cmd_test ??:0
torvalds#11 0x55788c5afbd0 in run_builtin perf.c:0
torvalds#12 0x55788c5afeeb in handle_internal_command perf.c:0
torvalds#13 0x55788c52b383 in main ??:0
torvalds#14 0x7fc12fe33ca8 in __libc_start_call_main libc_start_call_main.h:74
torvalds#15 0x7fc12fe33d65 in __libc_start_main@@GLIBC_2.34 libc-start.c:128
torvalds#16 0x55788c52b9d1 in _start ??:0
---- unexpected signal (2) ----
#0 0x55788c6210a3 in child_test_sig_handler builtin-test.c:0
#1 0x7fc12fe49df0 in __restore_rt libc_sigaction.c:0
#2 0x7fc12fea3a14 in pthread_sigmask@GLIBC_2.2.5 pthread_sigmask.c:45
#3 0x7fc12fe49fd9 in __GI___sigprocmask sigprocmask.c:26
#4 0x7fc12ff2601b in __longjmp_chk longjmp.c:36
#5 0x55788c6210c0 in print_test_result.isra.0 builtin-test.c:0
#6 0x7fc12fe49df0 in __restore_rt libc_sigaction.c:0
#7 0x7fc12fe99687 in __internal_syscall_cancel cancellation.c:64
#8 0x7fc12fee5f7a in clock_nanosleep@GLIBC_2.2.5 clock_nanosleep.c:72
#9 0x7fc12fef1393 in __nanosleep nanosleep.c:26
torvalds#10 0x7fc12ff02d68 in __sleep sleep.c:55
torvalds#11 0x55788c63196b in test__PERF_RECORD perf-record.c:0
torvalds#12 0x55788c620fb0 in run_test_child builtin-test.c:0
torvalds#13 0x55788c5bd18d in start_command run-command.c:127
torvalds#14 0x55788c621ef3 in __cmd_test builtin-test.c:0
torvalds#15 0x55788c6225bf in cmd_test ??:0
torvalds#16 0x55788c5afbd0 in run_builtin perf.c:0
torvalds#17 0x55788c5afeeb in handle_internal_command perf.c:0
torvalds#18 0x55788c52b383 in main ??:0
torvalds#19 0x7fc12fe33ca8 in __libc_start_call_main libc_start_call_main.h:74
torvalds#20 0x7fc12fe33d65 in __libc_start_main@@GLIBC_2.34 libc-start.c:128
torvalds#21 0x55788c52b9d1 in _start ??:0
7: PERF_RECORD_* events & perf_sample fields : Skip (permissions)
```
Signed-off-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20250624210500.2121303-1-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
heftig
pushed a commit
that referenced
this pull request
Aug 3, 2025
Calling perf top with branch filters enabled on Intel CPU's
with branch counters logging (A.K.A LBR event logging [1]) support
results in a segfault.
$ perf top -e '{cpu_core/cpu-cycles/,cpu_core/event=0xc6,umask=0x3,frontend=0x11,name=frontend_retired_dsb_miss/}' -j any,counter
...
Thread 27 "perf" received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7fffafff76c0 (LWP 949003)]
perf_env__find_br_cntr_info (env=0xf66dc0 <perf_env>, nr=0x0, width=0x7fffafff62c0) at util/env.c:653
653 *width = env->cpu_pmu_caps ? env->br_cntr_width :
(gdb) bt
#0 perf_env__find_br_cntr_info (env=0xf66dc0 <perf_env>, nr=0x0, width=0x7fffafff62c0) at util/env.c:653
#1 0x00000000005b1599 in symbol__account_br_cntr (branch=0x7fffcc3db580, evsel=0xfea2d0, offset=12, br_cntr=8) at util/annotate.c:345
#2 0x00000000005b17fb in symbol__account_cycles (addr=5658172, start=5658160, sym=0x7fffcc0ee420, cycles=539, evsel=0xfea2d0, br_cntr=8) at util/annotate.c:389
#3 0x00000000005b1976 in addr_map_symbol__account_cycles (ams=0x7fffcd7b01d0, start=0x7fffcd7b02b0, cycles=539, evsel=0xfea2d0, br_cntr=8) at util/annotate.c:422
#4 0x000000000068d57f in hist__account_cycles (bs=0x110d288, al=0x7fffafff6540, sample=0x7fffafff6760, nonany_branch_mode=false, total_cycles=0x0, evsel=0xfea2d0) at util/hist.c:2850
#5 0x0000000000446216 in hist_iter__top_callback (iter=0x7fffafff6590, al=0x7fffafff6540, single=true, arg=0x7fffffff9e00) at builtin-top.c:737
#6 0x0000000000689787 in hist_entry_iter__add (iter=0x7fffafff6590, al=0x7fffafff6540, max_stack_depth=127, arg=0x7fffffff9e00) at util/hist.c:1359
#7 0x0000000000446710 in perf_event__process_sample (tool=0x7fffffff9e00, event=0x110d250, evsel=0xfea2d0, sample=0x7fffafff6760, machine=0x108c968) at builtin-top.c:845
#8 0x0000000000447735 in deliver_event (qe=0x7fffffffa120, qevent=0x10fc200) at builtin-top.c:1211
#9 0x000000000064ccae in do_flush (oe=0x7fffffffa120, show_progress=false) at util/ordered-events.c:245
torvalds#10 0x000000000064d005 in __ordered_events__flush (oe=0x7fffffffa120, how=OE_FLUSH__TOP, timestamp=0) at util/ordered-events.c:324
torvalds#11 0x000000000064d0ef in ordered_events__flush (oe=0x7fffffffa120, how=OE_FLUSH__TOP) at util/ordered-events.c:342
torvalds#12 0x00000000004472a9 in process_thread (arg=0x7fffffff9e00) at builtin-top.c:1120
torvalds#13 0x00007ffff6e7dba8 in start_thread (arg=<optimized out>) at pthread_create.c:448
torvalds#14 0x00007ffff6f01b8c in __GI___clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:78
The cause is that perf_env__find_br_cntr_info tries to access a
null pointer pmu_caps in the perf_env struct. A similar issue exists
for homogeneous core systems which use the cpu_pmu_caps structure.
Fix this by populating cpu_pmu_caps and pmu_caps structures with
values from sysfs when calling perf top with branch stack sampling
enabled.
[1], LBR event logging introduced here:
https://lore.kernel.org/all/20231025201626.3000228-5-kan.liang@linux.intel.com/
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Thomas Falcon <thomas.falcon@intel.com>
Link: https://lore.kernel.org/r/20250612163659.1357950-2-thomas.falcon@intel.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
heftig
pushed a commit
that referenced
this pull request
Aug 15, 2025
The existing code move the VF NIC to new namespace when NETDEV_REGISTER is received on netvsc NIC. During deletion of the namespace, default_device_exit_batch() >> default_device_exit_net() is called. When netvsc NIC is moved back and registered to the default namespace, it automatically brings VF NIC back to the default namespace. This will cause the default_device_exit_net() >> for_each_netdev_safe loop unable to detect the list end, and hit NULL ptr: [ 231.449420] mana 7870:00:00.0 enP30832s1: Moved VF to namespace with: eth0 [ 231.449656] BUG: kernel NULL pointer dereference, address: 0000000000000010 [ 231.450246] #PF: supervisor read access in kernel mode [ 231.450579] #PF: error_code(0x0000) - not-present page [ 231.450916] PGD 17b8a8067 P4D 0 [ 231.451163] Oops: Oops: 0000 [#1] SMP NOPTI [ 231.451450] CPU: 82 UID: 0 PID: 1394 Comm: kworker/u768:1 Not tainted 6.16.0-rc4+ #3 VOLUNTARY [ 231.452042] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 11/21/2024 [ 231.452692] Workqueue: netns cleanup_net [ 231.452947] RIP: 0010:default_device_exit_batch+0x16c/0x3f0 [ 231.453326] Code: c0 0c f5 b3 e8 d5 db fe ff 48 85 c0 74 15 48 c7 c2 f8 fd ca b2 be 10 00 00 00 48 8d 7d c0 e8 7b 77 25 00 49 8b 86 28 01 00 00 <48> 8b 50 10 4c 8b 2a 4c 8d 62 f0 49 83 ed 10 4c 39 e0 0f 84 d6 00 [ 231.454294] RSP: 0018:ff75fc7c9bf9fd00 EFLAGS: 00010246 [ 231.454610] RAX: 0000000000000000 RBX: 0000000000000002 RCX: 61c8864680b583eb [ 231.455094] RDX: ff1fa9f71462d800 RSI: ff75fc7c9bf9fd38 RDI: 0000000030766564 [ 231.455686] RBP: ff75fc7c9bf9fd78 R08: 0000000000000000 R09: 0000000000000000 [ 231.456126] R10: 0000000000000001 R11: 0000000000000004 R12: ff1fa9f70088e340 [ 231.456621] R13: ff1fa9f70088e340 R14: ffffffffb3f50c20 R15: ff1fa9f7103e6340 [ 231.457161] FS: 0000000000000000(0000) GS:ff1faa6783a08000(0000) knlGS:0000000000000000 [ 231.457707] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 231.458031] CR2: 0000000000000010 CR3: 0000000179ab2006 CR4: 0000000000b73ef0 [ 231.458434] Call Trace: [ 231.458600] <TASK> [ 231.458777] ops_undo_list+0x100/0x220 [ 231.459015] cleanup_net+0x1b8/0x300 [ 231.459285] process_one_work+0x184/0x340 To fix it, move the ns change to a workqueue, and take rtnl_lock to avoid changing the netdev list when default_device_exit_net() is using it. Cc: stable@vger.kernel.org Fixes: 4c26280 ("hv_netvsc: Fix VF namespace also in synthetic NIC NETDEV_REGISTER event") Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com> Link: https://patch.msgid.link/1754511711-11188-1-git-send-email-haiyangz@linux.microsoft.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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https://bbs.archlinux.org/viewtopic.php?pid=1983671#p1983671