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Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
This will return EIO when __bread() fails to read SB, instead of EINVAL. Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
…INTK defined
error handling logic behaves differently with or without
CONFIG_PRINTK defined, since there are two copies of the same
function which a bit of different logic
One, when CONFIG_PRINTK is defined, code is
__btrfs_std_error(..)
{
::
save_error_info(fs_info);
if (sb->s_flags & MS_BORN)
btrfs_handle_error(fs_info);
}
and two when CONFIG_PRINTK is not defined, the code is
__btrfs_std_error(..)
{
::
if (sb->s_flags & MS_BORN) {
save_error_info(fs_info);
btrfs_handle_error(fs_info);
}
}
I doubt if this was intentional ? and appear to have caused since
we maintain two copies of the same function and they got diverged
with commits.
Now to decide which logic is correct reviewed changes as below,
533574c
Commit added two copies of this function
cf79ffb
Commit made change to only one copy of the function and to the
copy when CONFIG_PRINTK is defined.
To fix this, instead of maintaining two copies of same function
approach, maintain single function, and just put the extra
portion of the code under CONFIG_PRINTK define.
This patch just does that. And keeps code of with CONFIG_PRINTK
defined.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_error() and btrfs_std_error() does the same thing and calls _btrfs_std_error(), so consolidate them together. And the main motivation is that btrfs_error() is closely named with btrfs_err(), one handles error action the other is to log the error, so don't closely name them. Signed-off-by: Anand Jain <anand.jain@oracle.com> Suggested-by: David Sterba <dsterba@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
…ot found Use btrfs specific error code BTRFS_ERROR_DEV_MISSING_NOT_FOUND instead of -ENOENT. Next this removes the logging when user specifies "missing" and we don't find it in the kernel device list. Logging are for system events not for user input errors. Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
This uses a chunk of code from btrfs_read_dev_super() and creates a function called btrfs_read_dev_one_super() so that next patch can use it for scratch superblock. Signed-off-by: Anand Jain <anand.jain@oracle.com> [renamed bufhead to bh] Signed-off-by: David Sterba <dsterba@suse.com>
This patch updates and renames btrfs_scratch_superblocks, (which is used by the replace device thread), with those fixes from the scratch superblock code section of btrfs_rm_device(). The fixes are: Scratch all copies of superblock Notify kobject that superblock has been changed Update time on the device So that btrfs_rm_device() can use the function btrfs_scratch_superblocks() instead of its own scratch code. And further replace deivce code which similarly releases device back to the system, will have the fixes from the btrfs device delete. Signed-off-by: Anand Jain <anand.jain@oracle.com> [renamed to btrfs_scratch_superblock] Signed-off-by: David Sterba <dsterba@suse.com>
By general rule of thumb there shouldn't be any way that user land could trigger a kernel operation just by sending wrong arguments. Here do commit cleanups after user input has been verified. Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
Originally the message was not in a helper but ended up there. We should print error messages from callers instead. Signed-off-by: Anand Jain <anand.jain@oracle.com> [reworded subject and changelog] Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com> [reworded subject and changelog] Signed-off-by: David Sterba <dsterba@suse.com>
To avoid deadlock described in commit 084b6e7 ("btrfs: Fix a lockdep warning when running xfstest."), we should move kobj stuff out of dev_replace lock range. "It is because the btrfs_kobj_{add/rm}_device() will call memory allocation with GFP_KERNEL, which may flush fs page cache to free space, waiting for it self to do the commit, causing the deadlock. To solve the problem, move btrfs_kobj_{add/rm}_device() out of the dev_replace lock range, also involing split the btrfs_rm_dev_replace_srcdev() function into remove and free parts. Now only btrfs_rm_dev_replace_remove_srcdev() is called in dev_replace lock range, and kobj_{add/rm} and btrfs_rm_dev_replace_free_srcdev() are called out of the lock range." Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Anand Jain <anand.jain@oracle.com> [added lockup description] Signed-off-by: David Sterba <dsterba@suse.com>
This patch will log return value of add/del_qgroup_relation() and pass the err code of btrfs_run_qgroups to the btrfs_std_error(). Signed-off-by: Anand Jain <anand.jain@oracle.com>
A part of code from btrfs_scan_one_device() is moved to a new function btrfs_read_disk_super(), so that former function looks cleaner and moves the code to ensure null terminating label to it as well. Further there is opportunity to merge various duplicate code on read disk super. Earlier attempt on this was highlighted that there was some issues for which there are multiple versions, however it was not clear what was issue. So until its worked out we can keep it in a separate function. Signed-off-by: Anand Jain <anand.jain@oracle.com>
Optional Label may or may not be set, or it might be set at some time later. However while debugging to search through the kernel logs the scripts would need the logs to be consistent, so logs search key words shouldn't depend on the optional variables, instead fsid is better. Signed-off-by: Anand Jain <anand.jain@oracle.com>
From the issue diagnosable point of view, log if the device path is changed. Signed-off-by: Anand Jain <anand.jain@oracle.com>
Looks like oversight, call brelse() when checksum fails. Further down the code, in the non error path, we do call brelse() and so we don't see brelse() in the goto error paths. Signed-off-by: Anand Jain <anand.jain@oracle.com>
This adds an enhancement to show the seed fsid and its devices
on the btrfs sysfs.
The way sprouting handles fs_devices:
clone seed fs_devices and add to the fs_uuids
mem copy seed fs_devices and assign to fs_devices->seed (move dev_list)
evacuate seed fs_devices contents to hold sprout fs devices contents
So to be inline with this fs_devices changes during seeding,
represent seed fsid under the sprout fsid, this is achieved
by using the kobject_move()
The end result will be,
/sys/fs/btrfs/sprout-fsid/seed/level-1-seed-fsid/seed/(if)level-2-seed-fsid
Signed-off-by: Anand Jain <anand.jain@oracle.com>
We need fsid kobject to hold pool attributes however its created only when fs is mounted. So, this patch changes the life cycle of the fsid and devices kobjects /sys/fs/btrfs/<fsid> and /sys/fs/btrfs/<fsid>/devices, from created and destroyed by mount and unmount event to created and destroyed by scanned and module-unload events respectively. However this does not alter life cycle of fs attributes as such. Signed-off-by: Anand Jain <anand.jain@oracle.com>
move a section of btrfs_rm_device() code to check for min number
of the devices into the function __check_raid_min_devices()
v2: commit update and title renamed from
Btrfs: move check for min number of devices to a function
Signed-off-by: Anand Jain <anand.jain@oracle.com>
__check_raid_min_device() which was pealed from btrfs_rm_device() maintianed its original code to show the block move. This patch cleans up __check_raid_min_device(). Signed-off-by: Anand Jain <anand.jain@oracle.com>
The patch renames btrfs_dev_replace_find_srcdev() to
btrfs_find_device_by_user_input() and moves it to volumes.c.
so that delete device can use it.
v2: changed title from
'Btrfs: create rename btrfs_dev_replace_find_srcdev()'
and commit update
Signed-off-by: Anand Jain <anand.jain@oracle.com>
btrfs_rm_device() has a section of the code which can be replaced btrfs_find_device_by_user_input() Signed-off-by: Anand Jain <anand.jain@oracle.com>
The operation of device replace and device delete follows same steps upto some depth with in btrfs kernel, however they don't share codes. This enhancement will help replace and delete to share codes. Btrfs: enhance check device_path in btrfs_find_device_by_user_input() Signed-off-by: Anand Jain <anand.jain@oracle.com>
With the previous patches now the btrfs_scratch_superblocks() is ready to be used in btrfs_rm_device() so use it. Signed-off-by: Anand Jain <anand.jain@oracle.com>
This introduces new ioctl BTRFS_IOC_RM_DEV_V2, which uses enhanced struct btrfs_ioctl_vol_args_v2 to carry devid as an user argument. The patch won't delete the old ioctl interface and remains backward compatible with user land progs. Test case/script: echo "0 $(blockdev --getsz /dev/sdf) linear /dev/sdf 0" | dmsetup create bad_disk mkfs.btrfs -f -d raid1 -m raid1 /dev/sdd /dev/sde /dev/mapper/bad_disk mount /dev/sdd /btrfs dmsetup suspend bad_disk echo "0 $(blockdev --getsz /dev/sdf) error /dev/sdf 0" | dmsetup load bad_disk dmsetup resume bad_disk echo "bad disk failed. now deleting/replacing" btrfs dev del 3 /btrfs echo $? btrfs fi show /btrfs umount /btrfs btrfs-show-super /dev/sdd | egrep num_device dmsetup remove bad_disk wipefs -a /dev/sdf Signed-off-by: Anand Jain <anand.jain@oracle.com> Reported-by: Martin <m_btrfs@ml1.co.uk>
Not yet ready for integration, for review of the sysfs layout.
This patch makes btrfs_fs_devices and btrfs_device information readable
from sysfs. This uses the sysfs group visible entry point to mark certain
attributes visible/hidden depending the FS state.
The new extended layout is as shown below.
/sys/fs/btrfs/
./7b047f4d-c2ce-4f22-94a3-68c09057f1bf*
fsid*
missing_devices
num_devices*
open_devices
opened*
rotating
rw_devices
seeding
total_devices*
total_rw_bytes
./e6701882-220a-4416-98ac-a99f095bddcc*
active_pending
bdev
bytes_used
can_discard
devid*
dev_root_fsid
devstats_valid
dev_totalbytes
generation*
in_fs_metadata
io_align
io_width
missing
name*
nobarriers
replace_tgtdev
sector_size
total_bytes
type
uuid*
writeable
(* indicates that attribute will be visible even when device is
unmounted but registered with btrfs kernel)
v2: use btrfs_error() not btrfs_err()
reword subject form :
Btrfs: add sysfs layout to show btrfs_fs_devices and btrfs_device attributes
Signed-off-by: Anand Jain <anand.jain@oracle.com>
kdave
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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>
kdave
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This reverts commit 7796c97. This patch broke Dragonboard 845c (sdm845). I see: Unexpected kernel BRK exception at EL1 Internal error: BRK handler: 00000000f20003e8 [#1] SMP pc : qcom_swrm_set_channel_map+0x7c/0x80 [soundwire_qcom] lr : snd_soc_dai_set_channel_map+0x34/0x78 Call trace: qcom_swrm_set_channel_map+0x7c/0x80 [soundwire_qcom] (P) sdm845_dai_init+0x18c/0x2e0 [snd_soc_sdm845] snd_soc_link_init+0x28/0x6c snd_soc_bind_card+0x5f4/0xb0c snd_soc_register_card+0x148/0x1a4 devm_snd_soc_register_card+0x50/0xb0 sdm845_snd_platform_probe+0x124/0x148 [snd_soc_sdm845] platform_probe+0x6c/0xd0 really_probe+0xc0/0x2a4 __driver_probe_device+0x7c/0x130 driver_probe_device+0x40/0x118 __device_attach_driver+0xc4/0x108 bus_for_each_drv+0x8c/0xf0 __device_attach+0xa4/0x198 device_initial_probe+0x18/0x28 bus_probe_device+0xb8/0xbc deferred_probe_work_func+0xac/0xfc process_one_work+0x244/0x658 worker_thread+0x1b4/0x360 kthread+0x148/0x228 ret_from_fork+0x10/0x20 Kernel panic - not syncing: BRK handler: Fatal exception Dan has also reported following issues with the original patch https://lore.kernel.org/all/33fe8fe7-719a-405a-9ed2-d9f816ce1d57@sabinyo.mountain/ Bug #1: The zeroeth element of ctrl->pconfig[] is supposed to be unused. We start counting at 1. However this code sets ctrl->pconfig[0].ch_mask = 128. Bug #2: There are SLIM_MAX_TX_PORTS (16) elements in tx_ch[] array but only QCOM_SDW_MAX_PORTS + 1 (15) in the ctrl->pconfig[] array so it corrupts memory like Yongqin Liu pointed out. Bug 3: Like Jie Gan pointed out, it erases all the tx information with the rx information. Cc: stable@vger.kernel.org # v6.15+ Signed-off-by: Amit Pundir <amit.pundir@linaro.org> Acked-by: Srinivas Kandagatla <srini@kernel.org> Link: https://lore.kernel.org/r/20250709174949.8541-1-amit.pundir@linaro.org Signed-off-by: Vinod Koul <vkoul@kernel.org>
kdave
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into HEAD KVM/riscv fixes for 6.16, take #2 - Disable vstimecmp before exiting to user-space - Move HGEI[E|P] CSR access to IMSIC virtualization
kdave
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With KASAN enabled, it is possible to get a slab out of bounds during mount to ksmbd due to missing check in parse_server_interfaces() (see below): BUG: KASAN: slab-out-of-bounds in parse_server_interfaces+0x14ee/0x1880 [cifs] Read of size 4 at addr ffff8881433dba98 by task mount/9827 CPU: 5 UID: 0 PID: 9827 Comm: mount Tainted: G OE 6.16.0-rc2-kasan #2 PREEMPT(voluntary) Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE Hardware name: Dell Inc. Precision Tower 3620/0MWYPT, BIOS 2.13.1 06/14/2019 Call Trace: <TASK> dump_stack_lvl+0x9f/0xf0 print_report+0xd1/0x670 __virt_addr_valid+0x22c/0x430 ? parse_server_interfaces+0x14ee/0x1880 [cifs] ? kasan_complete_mode_report_info+0x2a/0x1f0 ? parse_server_interfaces+0x14ee/0x1880 [cifs] kasan_report+0xd6/0x110 parse_server_interfaces+0x14ee/0x1880 [cifs] __asan_report_load_n_noabort+0x13/0x20 parse_server_interfaces+0x14ee/0x1880 [cifs] ? __pfx_parse_server_interfaces+0x10/0x10 [cifs] ? trace_hardirqs_on+0x51/0x60 SMB3_request_interfaces+0x1ad/0x3f0 [cifs] ? __pfx_SMB3_request_interfaces+0x10/0x10 [cifs] ? SMB2_tcon+0x23c/0x15d0 [cifs] smb3_qfs_tcon+0x173/0x2b0 [cifs] ? __pfx_smb3_qfs_tcon+0x10/0x10 [cifs] ? cifs_get_tcon+0x105d/0x2120 [cifs] ? do_raw_spin_unlock+0x5d/0x200 ? cifs_get_tcon+0x105d/0x2120 [cifs] ? __pfx_smb3_qfs_tcon+0x10/0x10 [cifs] cifs_mount_get_tcon+0x369/0xb90 [cifs] ? dfs_cache_find+0xe7/0x150 [cifs] dfs_mount_share+0x985/0x2970 [cifs] ? check_path.constprop.0+0x28/0x50 ? save_trace+0x54/0x370 ? __pfx_dfs_mount_share+0x10/0x10 [cifs] ? __lock_acquire+0xb82/0x2ba0 ? __kasan_check_write+0x18/0x20 cifs_mount+0xbc/0x9e0 [cifs] ? __pfx_cifs_mount+0x10/0x10 [cifs] ? do_raw_spin_unlock+0x5d/0x200 ? cifs_setup_cifs_sb+0x29d/0x810 [cifs] cifs_smb3_do_mount+0x263/0x1990 [cifs] Reported-by: Namjae Jeon <linkinjeon@kernel.org> Tested-by: Namjae Jeon <linkinjeon@kernel.org> Cc: stable@vger.kernel.org Signed-off-by: Steve French <stfrench@microsoft.com>
kdave
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The commit under the Fixes tag added a netdev_assert_locked() in bnxt_free_ntp_fltrs(). The lock should be held during normal run-time but the assert will be triggered (see below) during bnxt_remove_one() which should not need the lock. The netdev is already unregistered by then. Fix it by calling netdev_assert_locked_or_invisible() which will not assert if the netdev is unregistered. WARNING: CPU: 5 PID: 2241 at ./include/net/netdev_lock.h:17 bnxt_free_ntp_fltrs+0xf8/0x100 [bnxt_en] Modules linked in: rpcrdma rdma_cm iw_cm ib_cm configfs ib_core bnxt_en(-) bridge stp llc x86_pkg_temp_thermal xfs tg3 [last unloaded: bnxt_re] CPU: 5 UID: 0 PID: 2241 Comm: rmmod Tainted: G S W 6.16.0 #2 PREEMPT(voluntary) Tainted: [S]=CPU_OUT_OF_SPEC, [W]=WARN Hardware name: Dell Inc. PowerEdge R730/072T6D, BIOS 2.4.3 01/17/2017 RIP: 0010:bnxt_free_ntp_fltrs+0xf8/0x100 [bnxt_en] Code: 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc 48 8b 47 60 be ff ff ff ff 48 8d b8 28 0c 00 00 e8 d0 cf 41 c3 85 c0 0f 85 2e ff ff ff <0f> 0b e9 27 ff ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffa92082387da0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff9e5b593d8000 RCX: 0000000000000001 RDX: 0000000000000001 RSI: ffffffff83dc9a70 RDI: ffffffff83e1a1cf RBP: ffff9e5b593d8c80 R08: 0000000000000000 R09: ffffffff8373a2b3 R10: 000000008100009f R11: 0000000000000001 R12: 0000000000000001 R13: ffffffffc01c4478 R14: dead000000000122 R15: dead000000000100 FS: 00007f3a8a52c740(0000) GS:ffff9e631ad1c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055bb289419c8 CR3: 000000011274e001 CR4: 00000000003706f0 Call Trace: <TASK> bnxt_remove_one+0x57/0x180 [bnxt_en] pci_device_remove+0x39/0xc0 device_release_driver_internal+0xa5/0x130 driver_detach+0x42/0x90 bus_remove_driver+0x61/0xc0 pci_unregister_driver+0x38/0x90 bnxt_exit+0xc/0x7d0 [bnxt_en] Fixes: 004b500 ("eth: bnxt: remove most dependencies on RTNL") Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com> Signed-off-by: Michael Chan <michael.chan@broadcom.com> Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev> Link: https://patch.msgid.link/20250816183850.4125033-1-michael.chan@broadcom.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Aug 21, 2025
…dlock When a user creates a dualpi2 qdisc it automatically sets a timer. This timer will run constantly and update the qdisc's probability field. The issue is that the timer acquires the qdisc root lock and runs in hardirq. The qdisc root lock is also acquired in dev.c whenever a packet arrives for this qdisc. Since the dualpi2 timer callback runs in hardirq, it may interrupt the packet processing running in softirq. If that happens and it runs on the same CPU, it will acquire the same lock and cause a deadlock. The following splat shows up when running a kernel compiled with lock debugging: [ +0.000224] WARNING: inconsistent lock state [ +0.000224] 6.16.0+ #10 Not tainted [ +0.000169] -------------------------------- [ +0.000029] inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage. [ +0.000000] ping/156 [HC0[0]:SC0[2]:HE1:SE0] takes: [ +0.000000] ffff897841242110 (&sch->root_lock_key){?.-.}-{3:3}, at: __dev_queue_xmit+0x86d/0x1140 [ +0.000000] {IN-HARDIRQ-W} state was registered at: [ +0.000000] lock_acquire.part.0+0xb6/0x220 [ +0.000000] _raw_spin_lock+0x31/0x80 [ +0.000000] dualpi2_timer+0x6f/0x270 [ +0.000000] __hrtimer_run_queues+0x1c5/0x360 [ +0.000000] hrtimer_interrupt+0x115/0x260 [ +0.000000] __sysvec_apic_timer_interrupt+0x6d/0x1a0 [ +0.000000] sysvec_apic_timer_interrupt+0x6e/0x80 [ +0.000000] asm_sysvec_apic_timer_interrupt+0x1a/0x20 [ +0.000000] pv_native_safe_halt+0xf/0x20 [ +0.000000] default_idle+0x9/0x10 [ +0.000000] default_idle_call+0x7e/0x1e0 [ +0.000000] do_idle+0x1e8/0x250 [ +0.000000] cpu_startup_entry+0x29/0x30 [ +0.000000] rest_init+0x151/0x160 [ +0.000000] start_kernel+0x6f3/0x700 [ +0.000000] x86_64_start_reservations+0x24/0x30 [ +0.000000] x86_64_start_kernel+0xc8/0xd0 [ +0.000000] common_startup_64+0x13e/0x148 [ +0.000000] irq event stamp: 6884 [ +0.000000] hardirqs last enabled at (6883): [<ffffffffa75700b3>] neigh_resolve_output+0x223/0x270 [ +0.000000] hardirqs last disabled at (6882): [<ffffffffa7570078>] neigh_resolve_output+0x1e8/0x270 [ +0.000000] softirqs last enabled at (6880): [<ffffffffa757006b>] neigh_resolve_output+0x1db/0x270 [ +0.000000] softirqs last disabled at (6884): [<ffffffffa755b533>] __dev_queue_xmit+0x73/0x1140 [ +0.000000] other info that might help us debug this: [ +0.000000] Possible unsafe locking scenario: [ +0.000000] CPU0 [ +0.000000] ---- [ +0.000000] lock(&sch->root_lock_key); [ +0.000000] <Interrupt> [ +0.000000] lock(&sch->root_lock_key); [ +0.000000] *** DEADLOCK *** [ +0.000000] 4 locks held by ping/156: [ +0.000000] #0: ffff897842332e08 (sk_lock-AF_INET){+.+.}-{0:0}, at: raw_sendmsg+0x41e/0xf40 [ +0.000000] #1: ffffffffa816f880 (rcu_read_lock){....}-{1:3}, at: ip_output+0x2c/0x190 [ +0.000000] #2: ffffffffa816f880 (rcu_read_lock){....}-{1:3}, at: ip_finish_output2+0xad/0x950 [ +0.000000] #3: ffffffffa816f840 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x73/0x1140 I am able to reproduce it consistently when running the following: tc qdisc add dev lo handle 1: root dualpi2 ping -f 127.0.0.1 To fix it, make the timer run in softirq. Fixes: 320d031 ("sched: Struct definition and parsing of dualpi2 qdisc") Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20250815135317.664993-1-victor@mojatatu.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
kdave
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Aug 25, 2025
Commit 3c7ac40 ("scsi: ufs: core: Delegate the interrupt service routine to a threaded IRQ handler") introduced an IRQ lock inversion issue. Fix this lock inversion by changing the spin_lock_irq() calls into spin_lock_irqsave() calls in code that can be called either from interrupt context or from thread context. This patch fixes the following lockdep complaint: WARNING: possible irq lock inversion dependency detected 6.12.30-android16-5-maybe-dirty-4k #1 Tainted: G W OE -------------------------------------------------------- kworker/u28:0/12 just changed the state of lock: ffffff881e29dd60 (&hba->clk_gating.lock){-...}-{2:2}, at: ufshcd_release_scsi_cmd+0x60/0x110 but this lock took another, HARDIRQ-unsafe lock in the past: (shost->host_lock){+.+.}-{2:2} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(shost->host_lock); local_irq_disable(); lock(&hba->clk_gating.lock); lock(shost->host_lock); <Interrupt> lock(&hba->clk_gating.lock); *** DEADLOCK *** 4 locks held by kworker/u28:0/12: #0: ffffff8800ac6158 ((wq_completion)async){+.+.}-{0:0}, at: process_one_work+0x1bc/0x65c #1: ffffffc085c93d70 ((work_completion)(&entry->work)){+.+.}-{0:0}, at: process_one_work+0x1e4/0x65c #2: ffffff881e29c0e0 (&shost->scan_mutex){+.+.}-{3:3}, at: __scsi_add_device+0x74/0x120 #3: ffffff881960ea00 (&hwq->cq_lock){-...}-{2:2}, at: ufshcd_mcq_poll_cqe_lock+0x28/0x104 the shortest dependencies between 2nd lock and 1st lock: -> (shost->host_lock){+.+.}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x134/0x2b4 _raw_spin_lock+0x48/0x64 ufshcd_sl_intr+0x4c/0xa08 ufshcd_threaded_intr+0x70/0x12c irq_thread_fn+0x48/0xa8 irq_thread+0x130/0x1ec kthread+0x110/0x134 ret_from_fork+0x10/0x20 SOFTIRQ-ON-W at: lock_acquire+0x134/0x2b4 _raw_spin_lock+0x48/0x64 ufshcd_sl_intr+0x4c/0xa08 ufshcd_threaded_intr+0x70/0x12c irq_thread_fn+0x48/0xa8 irq_thread+0x130/0x1ec kthread+0x110/0x134 ret_from_fork+0x10/0x20 INITIAL USE at: lock_acquire+0x134/0x2b4 _raw_spin_lock+0x48/0x64 ufshcd_sl_intr+0x4c/0xa08 ufshcd_threaded_intr+0x70/0x12c irq_thread_fn+0x48/0xa8 irq_thread+0x130/0x1ec kthread+0x110/0x134 ret_from_fork+0x10/0x20 } ... key at: [<ffffffc085ba1a98>] scsi_host_alloc.__key+0x0/0x10 ... acquired at: _raw_spin_lock_irqsave+0x5c/0x80 __ufshcd_release+0x78/0x118 ufshcd_send_uic_cmd+0xe4/0x118 ufshcd_dme_set_attr+0x88/0x1c8 ufs_google_phy_initialization+0x68/0x418 [ufs] ufs_google_link_startup_notify+0x78/0x27c [ufs] ufshcd_link_startup+0x84/0x720 ufshcd_init+0xf3c/0x1330 ufshcd_pltfrm_init+0x728/0x7d8 ufs_google_probe+0x30/0x84 [ufs] platform_probe+0xa0/0xe0 really_probe+0x114/0x454 __driver_probe_device+0xa4/0x160 driver_probe_device+0x44/0x23c __driver_attach_async_helper+0x60/0xd4 async_run_entry_fn+0x4c/0x17c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 -> (&hba->clk_gating.lock){-...}-{2:2} { IN-HARDIRQ-W at: lock_acquire+0x134/0x2b4 _raw_spin_lock_irqsave+0x5c/0x80 ufshcd_release_scsi_cmd+0x60/0x110 ufshcd_compl_one_cqe+0x2c0/0x3f4 ufshcd_mcq_poll_cqe_lock+0xb0/0x104 ufs_google_mcq_intr+0x80/0xa0 [ufs] __handle_irq_event_percpu+0x104/0x32c handle_irq_event+0x40/0x9c handle_fasteoi_irq+0x170/0x2e8 generic_handle_domain_irq+0x58/0x80 gic_handle_irq+0x48/0x104 call_on_irq_stack+0x3c/0x50 do_interrupt_handler+0x7c/0xd8 el1_interrupt+0x34/0x58 el1h_64_irq_handler+0x18/0x24 el1h_64_irq+0x68/0x6c _raw_spin_unlock_irqrestore+0x3c/0x6c debug_object_assert_init+0x16c/0x21c __mod_timer+0x4c/0x48c schedule_timeout+0xd4/0x16c io_schedule_timeout+0x48/0x70 do_wait_for_common+0x100/0x194 wait_for_completion_io_timeout+0x48/0x6c blk_execute_rq+0x124/0x17c scsi_execute_cmd+0x18c/0x3f8 scsi_probe_and_add_lun+0x204/0xd74 __scsi_add_device+0xbc/0x120 ufshcd_async_scan+0x80/0x3c0 async_run_entry_fn+0x4c/0x17c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 INITIAL USE at: lock_acquire+0x134/0x2b4 _raw_spin_lock_irqsave+0x5c/0x80 ufshcd_hold+0x34/0x14c ufshcd_send_uic_cmd+0x28/0x118 ufshcd_dme_set_attr+0x88/0x1c8 ufs_google_phy_initialization+0x68/0x418 [ufs] ufs_google_link_startup_notify+0x78/0x27c [ufs] ufshcd_link_startup+0x84/0x720 ufshcd_init+0xf3c/0x1330 ufshcd_pltfrm_init+0x728/0x7d8 ufs_google_probe+0x30/0x84 [ufs] platform_probe+0xa0/0xe0 really_probe+0x114/0x454 __driver_probe_device+0xa4/0x160 driver_probe_device+0x44/0x23c __driver_attach_async_helper+0x60/0xd4 async_run_entry_fn+0x4c/0x17c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 } ... key at: [<ffffffc085ba6fe8>] ufshcd_init.__key+0x0/0x10 ... acquired at: mark_lock+0x1c4/0x224 __lock_acquire+0x438/0x2e1c lock_acquire+0x134/0x2b4 _raw_spin_lock_irqsave+0x5c/0x80 ufshcd_release_scsi_cmd+0x60/0x110 ufshcd_compl_one_cqe+0x2c0/0x3f4 ufshcd_mcq_poll_cqe_lock+0xb0/0x104 ufs_google_mcq_intr+0x80/0xa0 [ufs] __handle_irq_event_percpu+0x104/0x32c handle_irq_event+0x40/0x9c handle_fasteoi_irq+0x170/0x2e8 generic_handle_domain_irq+0x58/0x80 gic_handle_irq+0x48/0x104 call_on_irq_stack+0x3c/0x50 do_interrupt_handler+0x7c/0xd8 el1_interrupt+0x34/0x58 el1h_64_irq_handler+0x18/0x24 el1h_64_irq+0x68/0x6c _raw_spin_unlock_irqrestore+0x3c/0x6c debug_object_assert_init+0x16c/0x21c __mod_timer+0x4c/0x48c schedule_timeout+0xd4/0x16c io_schedule_timeout+0x48/0x70 do_wait_for_common+0x100/0x194 wait_for_completion_io_timeout+0x48/0x6c blk_execute_rq+0x124/0x17c scsi_execute_cmd+0x18c/0x3f8 scsi_probe_and_add_lun+0x204/0xd74 __scsi_add_device+0xbc/0x120 ufshcd_async_scan+0x80/0x3c0 async_run_entry_fn+0x4c/0x17c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 stack backtrace: CPU: 6 UID: 0 PID: 12 Comm: kworker/u28:0 Tainted: G W OE 6.12.30-android16-5-maybe-dirty-4k #1 ccd4020fe444bdf629efc3b86df6be920b8df7d0 Tainted: [W]=WARN, [O]=OOT_MODULE, [E]=UNSIGNED_MODULE Hardware name: Spacecraft board based on MALIBU (DT) Workqueue: async async_run_entry_fn Call trace: dump_backtrace+0xfc/0x17c show_stack+0x18/0x28 dump_stack_lvl+0x40/0xa0 dump_stack+0x18/0x24 print_irq_inversion_bug+0x2fc/0x304 mark_lock_irq+0x388/0x4fc mark_lock+0x1c4/0x224 __lock_acquire+0x438/0x2e1c lock_acquire+0x134/0x2b4 _raw_spin_lock_irqsave+0x5c/0x80 ufshcd_release_scsi_cmd+0x60/0x110 ufshcd_compl_one_cqe+0x2c0/0x3f4 ufshcd_mcq_poll_cqe_lock+0xb0/0x104 ufs_google_mcq_intr+0x80/0xa0 [ufs dd6f385554e109da094ab91d5f7be18625a2222a] __handle_irq_event_percpu+0x104/0x32c handle_irq_event+0x40/0x9c handle_fasteoi_irq+0x170/0x2e8 generic_handle_domain_irq+0x58/0x80 gic_handle_irq+0x48/0x104 call_on_irq_stack+0x3c/0x50 do_interrupt_handler+0x7c/0xd8 el1_interrupt+0x34/0x58 el1h_64_irq_handler+0x18/0x24 el1h_64_irq+0x68/0x6c _raw_spin_unlock_irqrestore+0x3c/0x6c debug_object_assert_init+0x16c/0x21c __mod_timer+0x4c/0x48c schedule_timeout+0xd4/0x16c io_schedule_timeout+0x48/0x70 do_wait_for_common+0x100/0x194 wait_for_completion_io_timeout+0x48/0x6c blk_execute_rq+0x124/0x17c scsi_execute_cmd+0x18c/0x3f8 scsi_probe_and_add_lun+0x204/0xd74 __scsi_add_device+0xbc/0x120 ufshcd_async_scan+0x80/0x3c0 async_run_entry_fn+0x4c/0x17c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 Cc: Neil Armstrong <neil.armstrong@linaro.org> Cc: André Draszik <andre.draszik@linaro.org> Reviewed-by: Peter Wang <peter.wang@mediatek.com> Fixes: 3c7ac40 ("scsi: ufs: core: Delegate the interrupt service routine to a threaded IRQ handler") Signed-off-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20250815155842.472867-2-bvanassche@acm.org Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
kdave
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With CONFIG_DEBUG_OBJECTS_TIMERS unloading hfcpci module leads to the following splat: [ 250.215892] ODEBUG: assert_init not available (active state 0) object: ffffffffc01a3dc0 object type: timer_list hint: 0x0 [ 250.217520] WARNING: CPU: 0 PID: 233 at lib/debugobjects.c:612 debug_print_object+0x1b6/0x2c0 [ 250.218775] Modules linked in: hfcpci(-) mISDN_core [ 250.219537] CPU: 0 UID: 0 PID: 233 Comm: rmmod Not tainted 6.17.0-rc2-g6f713187ac98 #2 PREEMPT(voluntary) [ 250.220940] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 250.222377] RIP: 0010:debug_print_object+0x1b6/0x2c0 [ 250.223131] Code: fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 4f 41 56 48 8b 14 dd a0 4e 01 9f 48 89 ee 48 c7 c7 20 46 01 9f e8 cb 84d [ 250.225805] RSP: 0018:ffff888015ea7c08 EFLAGS: 00010286 [ 250.226608] RAX: 0000000000000000 RBX: 0000000000000005 RCX: ffffffff9be93a95 [ 250.227708] RDX: 1ffff1100d945138 RSI: 0000000000000008 RDI: ffff88806ca289c0 [ 250.228993] RBP: ffffffff9f014a00 R08: 0000000000000001 R09: ffffed1002bd4f39 [ 250.230043] R10: ffff888015ea79cf R11: 0000000000000001 R12: 0000000000000001 [ 250.231185] R13: ffffffff9eea0520 R14: 0000000000000000 R15: ffff888015ea7cc8 [ 250.232454] FS: 00007f3208f01540(0000) GS:ffff8880caf5a000(0000) knlGS:0000000000000000 [ 250.233851] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 250.234856] CR2: 00007f32090a7421 CR3: 0000000004d63000 CR4: 00000000000006f0 [ 250.236117] Call Trace: [ 250.236599] <TASK> [ 250.236967] ? trace_irq_enable.constprop.0+0xd4/0x130 [ 250.237920] debug_object_assert_init+0x1f6/0x310 [ 250.238762] ? __pfx_debug_object_assert_init+0x10/0x10 [ 250.239658] ? __lock_acquire+0xdea/0x1c70 [ 250.240369] __try_to_del_timer_sync+0x69/0x140 [ 250.241172] ? __pfx___try_to_del_timer_sync+0x10/0x10 [ 250.242058] ? __timer_delete_sync+0xc6/0x120 [ 250.242842] ? lock_acquire+0x30/0x80 [ 250.243474] ? __timer_delete_sync+0xc6/0x120 [ 250.244262] __timer_delete_sync+0x98/0x120 [ 250.245015] HFC_cleanup+0x10/0x20 [hfcpci] [ 250.245704] __do_sys_delete_module+0x348/0x510 [ 250.246461] ? __pfx___do_sys_delete_module+0x10/0x10 [ 250.247338] do_syscall_64+0xc1/0x360 [ 250.247924] entry_SYSCALL_64_after_hwframe+0x77/0x7f Fix this by initializing hfc_tl timer with DEFINE_TIMER macro. Also, use mod_timer instead of manual timeout update. Fixes: 87c5fa1 ("mISDN: Add different different timer settings for hfc-pci") Fixes: 175302f ("mISDN: hfcpci: Fix use-after-free bug in hfcpci_softirq") Signed-off-by: Vladimir Riabchun <ferr.lambarginio@gmail.com> Link: https://patch.msgid.link/aKiy2D_LiWpQ5kXq@vova-pc Signed-off-by: Jakub Kicinski <kuba@kernel.org>
kdave
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Aug 29, 2025
These iterations require the read lock, otherwise RCU lockdep will splat: ============================= WARNING: suspicious RCU usage 6.17.0-rc3-00014-g31419c045d64 #6 Tainted: G O ----------------------------- drivers/base/power/main.c:1333 RCU-list traversed in non-reader section!! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 5 locks held by rtcwake/547: #0: 00000000643ab418 (sb_writers#6){.+.+}-{0:0}, at: file_start_write+0x2b/0x3a #1: 0000000067a0ca88 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x181/0x24b #2: 00000000631eac40 (kn->active#3){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x191/0x24b #3: 00000000609a1308 (system_transition_mutex){+.+.}-{4:4}, at: pm_suspend+0xaf/0x30b #4: 0000000060c0fdb0 (device_links_srcu){.+.+}-{0:0}, at: device_links_read_lock+0x75/0x98 stack backtrace: CPU: 0 UID: 0 PID: 547 Comm: rtcwake Tainted: G O 6.17.0-rc3-00014-g31419c045d64 #6 VOLUNTARY Tainted: [O]=OOT_MODULE Stack: 223721b3a80 6089eac6 00000001 00000001 ffffff00 6089eac6 00000535 6086e528 721b3ac0 6003c294 00000000 60031fc0 Call Trace: [<600407ed>] show_stack+0x10e/0x127 [<6003c294>] dump_stack_lvl+0x77/0xc6 [<6003c2fd>] dump_stack+0x1a/0x20 [<600bc2f8>] lockdep_rcu_suspicious+0x116/0x13e [<603d8ea1>] dpm_async_suspend_superior+0x117/0x17e [<603d980f>] device_suspend+0x528/0x541 [<603da24b>] dpm_suspend+0x1a2/0x267 [<603da837>] dpm_suspend_start+0x5d/0x72 [<600ca0c9>] suspend_devices_and_enter+0xab/0x736 [...] Add the fourth argument to the iteration to annotate this and avoid the splat. Fixes: 0679963 ("PM: sleep: Make async suspend handle suppliers like parents") Fixes: ed18738 ("PM: sleep: Make async resume handle consumers like children") Signed-off-by: Johannes Berg <johannes.berg@intel.com> Link: https://patch.msgid.link/20250826134348.aba79f6e6299.I9ecf55da46ccf33778f2c018a82e1819d815b348@changeid Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
kdave
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Aug 29, 2025
If preparing a write bio fails then blk_zone_wplug_bio_work() calls
bio_endio() with zwplug->lock held. If a device mapper driver is stacked
on top of the zoned block device then this results in nested locking of
zwplug->lock. The resulting lockdep complaint is a false positive
because this is nested locking and not recursive locking. Suppress this
false positive by calling blk_zone_wplug_bio_io_error() without holding
zwplug->lock. This is safe because no code in
blk_zone_wplug_bio_io_error() depends on zwplug->lock being held. This
patch suppresses the following lockdep complaint:
WARNING: possible recursive locking detected
--------------------------------------------
kworker/3:0H/46 is trying to acquire lock:
ffffff882968b830 (&zwplug->lock){-...}-{2:2}, at: blk_zone_write_plug_bio_endio+0x64/0x1f0
but task is already holding lock:
ffffff88315bc230 (&zwplug->lock){-...}-{2:2}, at: blk_zone_wplug_bio_work+0x8c/0x48c
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&zwplug->lock);
lock(&zwplug->lock);
*** DEADLOCK ***
May be due to missing lock nesting notation
3 locks held by kworker/3:0H/46:
#0: ffffff8809486758 ((wq_completion)sdd_zwplugs){+.+.}-{0:0}, at: process_one_work+0x1bc/0x65c
#1: ffffffc085de3d70 ((work_completion)(&zwplug->bio_work)){+.+.}-{0:0}, at: process_one_work+0x1e4/0x65c
#2: ffffff88315bc230 (&zwplug->lock){-...}-{2:2}, at: blk_zone_wplug_bio_work+0x8c/0x48c
stack backtrace:
CPU: 3 UID: 0 PID: 46 Comm: kworker/3:0H Tainted: G W OE 6.12.38-android16-5-maybe-dirty-4k #1 8b362b6f76e3645a58cd27d86982bce10d150025
Tainted: [W]=WARN, [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
Hardware name: Spacecraft board based on MALIBU (DT)
Workqueue: sdd_zwplugs blk_zone_wplug_bio_work
Call trace:
dump_backtrace+0xfc/0x17c
show_stack+0x18/0x28
dump_stack_lvl+0x40/0xa0
dump_stack+0x18/0x24
print_deadlock_bug+0x38c/0x398
__lock_acquire+0x13e8/0x2e1c
lock_acquire+0x134/0x2b4
_raw_spin_lock_irqsave+0x5c/0x80
blk_zone_write_plug_bio_endio+0x64/0x1f0
bio_endio+0x9c/0x240
__dm_io_complete+0x214/0x260
clone_endio+0xe8/0x214
bio_endio+0x218/0x240
blk_zone_wplug_bio_work+0x204/0x48c
process_one_work+0x26c/0x65c
worker_thread+0x33c/0x498
kthread+0x110/0x134
ret_from_fork+0x10/0x20
Cc: stable@vger.kernel.org
Cc: Damien Le Moal <dlemoal@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Fixes: dd291d7 ("block: Introduce zone write plugging")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20250825182720.1697203-1-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
kdave
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In gicv5_irs_of_init_affinity() a WARN_ON() is triggered if:
1) a phandle in the "cpus" property does not correspond to a valid OF
node
2 a CPU logical id does not exist for a given OF cpu_node
#1 is a firmware bug and should be reported as such but does not warrant a
WARN_ON() backtrace.
#2 is not necessarily an error condition (eg a kernel can be booted with
nr_cpus=X limiting the number of cores artificially) and therefore there
is no reason to clutter the kernel log with WARN_ON() output when the
condition is hit.
Rework the IRS affinity parsing code to remove undue WARN_ON()s thus
making it less noisy.
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250814094138.1611017-1-lpieralisi@kernel.org
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…ux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 changes for 6.17, take #2 - Correctly handle 'invariant' system registers for protected VMs - Improved handling of VNCR data aborts, including external aborts - Fixes for handling of FEAT_RAS for NV guests, providing a sane fault context during SEA injection and preventing the use of RASv1p1 fault injection hardware - Ensure that page table destruction when a VM is destroyed gives an opportunity to reschedule - Large fix to KVM's infrastructure for managing guest context loaded on the CPU, addressing issues where the output of AT emulation doesn't get reflected to the guest - Fix AT S12 emulation to actually perform stage-2 translation when necessary - Avoid attempting vLPI irqbypass when GICv4 has been explicitly disabled for a VM - Minor KVM + selftest fixes
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When the "proxy" option is enabled on a VXLAN device, the device will suppress ARP requests and IPv6 Neighbor Solicitation messages if it is able to reply on behalf of the remote host. That is, if a matching and valid neighbor entry is configured on the VXLAN device whose MAC address is not behind the "any" remote (0.0.0.0 / ::). The code currently assumes that the FDB entry for the neighbor's MAC address points to a valid remote destination, but this is incorrect if the entry is associated with an FDB nexthop group. This can result in a NPD [1][3] which can be reproduced using [2][4]. Fix by checking that the remote destination exists before dereferencing it. [1] BUG: kernel NULL pointer dereference, address: 0000000000000000 [...] CPU: 4 UID: 0 PID: 365 Comm: arping Not tainted 6.17.0-rc2-virtme-g2a89cb21162c #2 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-4.fc41 04/01/2014 RIP: 0010:vxlan_xmit+0xb58/0x15f0 [...] Call Trace: <TASK> dev_hard_start_xmit+0x5d/0x1c0 __dev_queue_xmit+0x246/0xfd0 packet_sendmsg+0x113a/0x1850 __sock_sendmsg+0x38/0x70 __sys_sendto+0x126/0x180 __x64_sys_sendto+0x24/0x30 do_syscall_64+0xa4/0x260 entry_SYSCALL_64_after_hwframe+0x4b/0x53 [2] #!/bin/bash ip address add 192.0.2.1/32 dev lo ip nexthop add id 1 via 192.0.2.2 fdb ip nexthop add id 10 group 1 fdb ip link add name vx0 up type vxlan id 10010 local 192.0.2.1 dstport 4789 proxy ip neigh add 192.0.2.3 lladdr 00:11:22:33:44:55 nud perm dev vx0 bridge fdb add 00:11:22:33:44:55 dev vx0 self static nhid 10 arping -b -c 1 -s 192.0.2.1 -I vx0 192.0.2.3 [3] BUG: kernel NULL pointer dereference, address: 0000000000000000 [...] CPU: 13 UID: 0 PID: 372 Comm: ndisc6 Not tainted 6.17.0-rc2-virtmne-g6ee90cb26014 #3 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1v996), BIOS 1.17.0-4.fc41 04/01/2x014 RIP: 0010:vxlan_xmit+0x803/0x1600 [...] Call Trace: <TASK> dev_hard_start_xmit+0x5d/0x1c0 __dev_queue_xmit+0x246/0xfd0 ip6_finish_output2+0x210/0x6c0 ip6_finish_output+0x1af/0x2b0 ip6_mr_output+0x92/0x3e0 ip6_send_skb+0x30/0x90 rawv6_sendmsg+0xe6e/0x12e0 __sock_sendmsg+0x38/0x70 __sys_sendto+0x126/0x180 __x64_sys_sendto+0x24/0x30 do_syscall_64+0xa4/0x260 entry_SYSCALL_64_after_hwframe+0x4b/0x53 RIP: 0033:0x7f383422ec77 [4] #!/bin/bash ip address add 2001:db8:1::1/128 dev lo ip nexthop add id 1 via 2001:db8:1::1 fdb ip nexthop add id 10 group 1 fdb ip link add name vx0 up type vxlan id 10010 local 2001:db8:1::1 dstport 4789 proxy ip neigh add 2001:db8:1::3 lladdr 00:11:22:33:44:55 nud perm dev vx0 bridge fdb add 00:11:22:33:44:55 dev vx0 self static nhid 10 ndisc6 -r 1 -s 2001:db8:1::1 -w 1 2001:db8:1::3 vx0 Fixes: 1274e1c ("vxlan: ecmp support for mac fdb entries") Reviewed-by: Petr Machata <petrm@nvidia.com> Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org> Link: https://patch.msgid.link/20250901065035.159644-3-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Ido Schimmel says:
====================
vxlan: Fix NPDs when using nexthop objects
With FDB nexthop groups, VXLAN FDB entries do not necessarily point to
a remote destination but rather to an FDB nexthop group. This means that
first_remote_{rcu,rtnl}() can return NULL and a few places in the driver
were not ready for that, resulting in NULL pointer dereferences.
Patches #1-#2 fix these NPDs.
Note that vxlan_fdb_find_uc() still dereferences the remote returned by
first_remote_rcu() without checking that it is not NULL, but this
function is only invoked by a single driver which vetoes the creation of
FDB nexthop groups. I will patch this in net-next to make the code less
fragile.
Patch #3 adds a selftests which exercises these code paths and tests
basic Tx functionality with FDB nexthop groups. I verified that the test
crashes the kernel without the first two patches.
====================
Link: https://patch.msgid.link/20250901065035.159644-1-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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When transmitting a PTP frame which is timestamp using 2 step, the following warning appears if CONFIG_PROVE_LOCKING is enabled: ============================= [ BUG: Invalid wait context ] 6.17.0-rc1-00326-ge6160462704e torvalds#427 Not tainted ----------------------------- ptp4l/119 is trying to lock: c2a44ed4 (&vsc8531->ts_lock){+.+.}-{3:3}, at: vsc85xx_txtstamp+0x50/0xac other info that might help us debug this: context-{4:4} 4 locks held by ptp4l/119: #0: c145f068 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x58/0x1440 #1: c29df974 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_queue_xmit+0x5c4/0x1440 #2: c2aaaad0 (_xmit_ETHER#2){+.-.}-{2:2}, at: sch_direct_xmit+0x108/0x350 #3: c2aac170 (&lan966x->tx_lock){+.-.}-{2:2}, at: lan966x_port_xmit+0xd0/0x350 stack backtrace: CPU: 0 UID: 0 PID: 119 Comm: ptp4l Not tainted 6.17.0-rc1-00326-ge6160462704e torvalds#427 NONE Hardware name: Generic DT based system Call trace: unwind_backtrace from show_stack+0x10/0x14 show_stack from dump_stack_lvl+0x7c/0xac dump_stack_lvl from __lock_acquire+0x8e8/0x29dc __lock_acquire from lock_acquire+0x108/0x38c lock_acquire from __mutex_lock+0xb0/0xe78 __mutex_lock from mutex_lock_nested+0x1c/0x24 mutex_lock_nested from vsc85xx_txtstamp+0x50/0xac vsc85xx_txtstamp from lan966x_fdma_xmit+0xd8/0x3a8 lan966x_fdma_xmit from lan966x_port_xmit+0x1bc/0x350 lan966x_port_xmit from dev_hard_start_xmit+0xc8/0x2c0 dev_hard_start_xmit from sch_direct_xmit+0x8c/0x350 sch_direct_xmit from __dev_queue_xmit+0x680/0x1440 __dev_queue_xmit from packet_sendmsg+0xfa4/0x1568 packet_sendmsg from __sys_sendto+0x110/0x19c __sys_sendto from sys_send+0x18/0x20 sys_send from ret_fast_syscall+0x0/0x1c Exception stack(0xf0b05fa8 to 0xf0b05ff0) 5fa0: 00000001 0000000 0000000 0004b47a 0000003a 00000000 5fc0: 00000001 0000000 00000000 00000121 0004af58 00044874 00000000 00000000 5fe0: 00000001 bee9d420 00025a10 b6e75c7c So, instead of using the ts_lock for tx_queue, use the spinlock that skb_buff_head has. Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev> Fixes: 7d272e6 ("net: phy: mscc: timestamping and PHC support") Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com> Link: https://patch.msgid.link/20250902121259.3257536-1-horatiu.vultur@microchip.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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The commit ced17ee ("Revert "virtio: reject shm region if length is zero"") exposes the following DAX page fault bug (this fix the failure that getting shm region alway returns false because of zero length): The commit 21aa65b ("mm: remove callers of pfn_t functionality") handles the DAX physical page address incorrectly: the removed macro 'phys_to_pfn_t()' should be replaced with 'PHYS_PFN()'. [ 1.390321] BUG: unable to handle page fault for address: ffffd3fb40000008 [ 1.390875] #PF: supervisor read access in kernel mode [ 1.391257] #PF: error_code(0x0000) - not-present page [ 1.391509] PGD 0 P4D 0 [ 1.391626] Oops: Oops: 0000 [#1] SMP NOPTI [ 1.391806] CPU: 6 UID: 1000 PID: 162 Comm: weston Not tainted 6.17.0-rc3-WSL2-STABLE #2 PREEMPT(none) [ 1.392361] RIP: 0010:dax_to_folio+0x14/0x60 [ 1.392653] Code: 52 c9 c3 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 48 c1 ef 05 48 c1 e7 06 48 03 3d 34 b5 31 01 <48> 8b 57 08 48 89 f8 f6 c2 01 75 2b 66 90 c3 cc cc cc cc f7 c7 ff [ 1.393727] RSP: 0000:ffffaf7d04407aa8 EFLAGS: 00010086 [ 1.394003] RAX: 000000a000000000 RBX: ffffaf7d04407bb0 RCX: 0000000000000000 [ 1.394524] RDX: ffffd17b40000008 RSI: 0000000000000083 RDI: ffffd3fb40000000 [ 1.394967] RBP: 0000000000000011 R08: 000000a000000000 R09: 0000000000000000 [ 1.395400] R10: 0000000000001000 R11: ffffaf7d04407c10 R12: 0000000000000000 [ 1.395806] R13: ffffa020557be9c0 R14: 0000014000000001 R15: 0000725970e94000 [ 1.396268] FS: 000072596d6d2ec0(0000) GS:ffffa0222dc59000(0000) knlGS:0000000000000000 [ 1.396715] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1.397100] CR2: ffffd3fb40000008 CR3: 000000011579c005 CR4: 0000000000372ef0 [ 1.397518] Call Trace: [ 1.397663] <TASK> [ 1.397900] dax_insert_entry+0x13b/0x390 [ 1.398179] dax_fault_iter+0x2a5/0x6c0 [ 1.398443] dax_iomap_pte_fault+0x193/0x3c0 [ 1.398750] __fuse_dax_fault+0x8b/0x270 [ 1.398997] ? vm_mmap_pgoff+0x161/0x210 [ 1.399175] __do_fault+0x30/0x180 [ 1.399360] do_fault+0xc4/0x550 [ 1.399547] __handle_mm_fault+0x8e3/0xf50 [ 1.399731] ? do_syscall_64+0x72/0x1e0 [ 1.399958] handle_mm_fault+0x192/0x2f0 [ 1.400204] do_user_addr_fault+0x20e/0x700 [ 1.400418] exc_page_fault+0x66/0x150 [ 1.400602] asm_exc_page_fault+0x26/0x30 [ 1.400831] RIP: 0033:0x72596d1bf703 [ 1.401076] Code: 31 f6 45 31 e4 48 8d 15 b3 73 00 00 e8 06 03 00 00 8b 83 68 01 00 00 e9 8e fa ff ff 0f 1f 00 48 8b 44 24 08 4c 89 ee 48 89 df <c7> 00 21 43 34 12 e8 72 09 00 00 e9 6a fa ff ff 0f 1f 44 00 00 e8 [ 1.402172] RSP: 002b:00007ffc350f6dc0 EFLAGS: 00010202 [ 1.402488] RAX: 0000725970e94000 RBX: 00005b7c642c2560 RCX: 0000725970d359a7 [ 1.402898] RDX: 0000000000000003 RSI: 00007ffc350f6dc0 RDI: 00005b7c642c2560 [ 1.403284] RBP: 00007ffc350f6e90 R08: 000000000000000d R09: 0000000000000000 [ 1.403634] R10: 00007ffc350f6dd8 R11: 0000000000000246 R12: 0000000000000001 [ 1.404078] R13: 00007ffc350f6dc0 R14: 0000725970e29ce0 R15: 0000000000000003 [ 1.404450] </TASK> [ 1.404570] Modules linked in: [ 1.404821] CR2: ffffd3fb40000008 [ 1.405029] ---[ end trace 0000000000000000 ]--- [ 1.405323] RIP: 0010:dax_to_folio+0x14/0x60 [ 1.405556] Code: 52 c9 c3 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 48 c1 ef 05 48 c1 e7 06 48 03 3d 34 b5 31 01 <48> 8b 57 08 48 89 f8 f6 c2 01 75 2b 66 90 c3 cc cc cc cc f7 c7 ff [ 1.406639] RSP: 0000:ffffaf7d04407aa8 EFLAGS: 00010086 [ 1.406910] RAX: 000000a000000000 RBX: ffffaf7d04407bb0 RCX: 0000000000000000 [ 1.407379] RDX: ffffd17b40000008 RSI: 0000000000000083 RDI: ffffd3fb40000000 [ 1.407800] RBP: 0000000000000011 R08: 000000a000000000 R09: 0000000000000000 [ 1.408246] R10: 0000000000001000 R11: ffffaf7d04407c10 R12: 0000000000000000 [ 1.408666] R13: ffffa020557be9c0 R14: 0000014000000001 R15: 0000725970e94000 [ 1.409170] FS: 000072596d6d2ec0(0000) GS:ffffa0222dc59000(0000) knlGS:0000000000000000 [ 1.409608] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1.409977] CR2: ffffd3fb40000008 CR3: 000000011579c005 CR4: 0000000000372ef0 [ 1.410437] Kernel panic - not syncing: Fatal exception [ 1.410857] Kernel Offset: 0xc000000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) Fixes: 21aa65b ("mm: remove callers of pfn_t functionality") Signed-off-by: Haiyue Wang <haiyuewa@163.com> Link: https://lore.kernel.org/20250904120339.972-1-haiyuewa@163.com Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
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Problem description
===================
Lockdep reports a possible circular locking dependency (AB/BA) between
&pl->state_mutex and &phy->lock, as follows.
phylink_resolve() // acquires &pl->state_mutex
-> phylink_major_config()
-> phy_config_inband() // acquires &pl->phydev->lock
whereas all the other call sites where &pl->state_mutex and
&pl->phydev->lock have the locking scheme reversed. Everywhere else,
&pl->phydev->lock is acquired at the top level, and &pl->state_mutex at
the lower level. A clear example is phylink_bringup_phy().
The outlier is the newly introduced phy_config_inband() and the existing
lock order is the correct one. To understand why it cannot be the other
way around, it is sufficient to consider phylink_phy_change(), phylink's
callback from the PHY device's phy->phy_link_change() virtual method,
invoked by the PHY state machine.
phy_link_up() and phy_link_down(), the (indirect) callers of
phylink_phy_change(), are called with &phydev->lock acquired.
Then phylink_phy_change() acquires its own &pl->state_mutex, to
serialize changes made to its pl->phy_state and pl->link_config.
So all other instances of &pl->state_mutex and &phydev->lock must be
consistent with this order.
Problem impact
==============
I think the kernel runs a serious deadlock risk if an existing
phylink_resolve() thread, which results in a phy_config_inband() call,
is concurrent with a phy_link_up() or phy_link_down() call, which will
deadlock on &pl->state_mutex in phylink_phy_change(). Practically
speaking, the impact may be limited by the slow speed of the medium
auto-negotiation protocol, which makes it unlikely for the current state
to still be unresolved when a new one is detected, but I think the
problem is there. Nonetheless, the problem was discovered using lockdep.
Proposed solution
=================
Practically speaking, the phy_config_inband() requirement of having
phydev->lock acquired must transfer to the caller (phylink is the only
caller). There, it must bubble up until immediately before
&pl->state_mutex is acquired, for the cases where that takes place.
Solution details, considerations, notes
=======================================
This is the phy_config_inband() call graph:
sfp_upstream_ops :: connect_phy()
|
v
phylink_sfp_connect_phy()
|
v
phylink_sfp_config_phy()
|
| sfp_upstream_ops :: module_insert()
| |
| v
| phylink_sfp_module_insert()
| |
| | sfp_upstream_ops :: module_start()
| | |
| | v
| | phylink_sfp_module_start()
| | |
| v v
| phylink_sfp_config_optical()
phylink_start() | |
| phylink_resume() v v
| | phylink_sfp_set_config()
| | |
v v v
phylink_mac_initial_config()
| phylink_resolve()
| | phylink_ethtool_ksettings_set()
v v v
phylink_major_config()
|
v
phy_config_inband()
phylink_major_config() caller #1, phylink_mac_initial_config(), does not
acquire &pl->state_mutex nor do its callers. It must acquire
&pl->phydev->lock prior to calling phylink_major_config().
phylink_major_config() caller #2, phylink_resolve() acquires
&pl->state_mutex, thus also needs to acquire &pl->phydev->lock.
phylink_major_config() caller #3, phylink_ethtool_ksettings_set(), is
completely uninteresting, because it only calls phylink_major_config()
if pl->phydev is NULL (otherwise it calls phy_ethtool_ksettings_set()).
We need to change nothing there.
Other solutions
===============
The lock inversion between &pl->state_mutex and &pl->phydev->lock has
occurred at least once before, as seen in commit c718af2 ("net:
phylink: fix ethtool -A with attached PHYs"). The solution there was to
simply not call phy_set_asym_pause() under the &pl->state_mutex. That
cannot be extended to our case though, where the phy_config_inband()
call is much deeper inside the &pl->state_mutex section.
Fixes: 5fd0f1a ("net: phylink: add negotiation of in-band capabilities")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Link: https://patch.msgid.link/20250904125238.193990-2-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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5da3d94 ("PCI: mvebu: Use for_each_of_range() iterator for parsing "ranges"") simplified code by using the for_each_of_range() iterator, but it broke PCI enumeration on Turris Omnia (and probably other mvebu targets). Issue #1: To determine range.flags, of_pci_range_parser_one() uses bus->get_flags(), which resolves to of_bus_pci_get_flags(), which already returns an IORESOURCE bit field, and NOT the original flags from the "ranges" resource. Then mvebu_get_tgt_attr() attempts the very same conversion again. Remove the misinterpretation of range.flags in mvebu_get_tgt_attr(), to restore the intended behavior. Issue #2: The driver needs target and attributes, which are encoded in the raw address values of the "/soc/pcie/ranges" resource. According to of_pci_range_parser_one(), the raw values are stored in range.bus_addr and range.parent_bus_addr, respectively. range.cpu_addr is a translated version of range.parent_bus_addr, and not relevant here. Use the correct range structure member, to extract target and attributes. This restores the intended behavior. Fixes: 5da3d94 ("PCI: mvebu: Use for_each_of_range() iterator for parsing "ranges"") Reported-by: Jan Palus <jpalus@fastmail.com> Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220479 Signed-off-by: Klaus Kudielka <klaus.kudielka@gmail.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Tested-by: Tony Dinh <mibodhi@gmail.com> Tested-by: Jan Palus <jpalus@fastmail.com> Link: https://patch.msgid.link/20250907102303.29735-1-klaus.kudielka@gmail.com
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…ostcopy When you run a KVM guest with vhost-net and migrate that guest to another host, and you immediately enable postcopy after starting the migration, there is a big chance that the network connection of the guest won't work anymore on the destination side after the migration. With a debug kernel v6.16.0, there is also a call trace that looks like this: FAULT_FLAG_ALLOW_RETRY missing 881 CPU: 6 UID: 0 PID: 549 Comm: kworker/6:2 Kdump: loaded Not tainted 6.16.0 torvalds#56 NONE Hardware name: IBM 3931 LA1 400 (LPAR) Workqueue: events irqfd_inject [kvm] Call Trace: [<00003173cbecc634>] dump_stack_lvl+0x104/0x168 [<00003173cca69588>] handle_userfault+0xde8/0x1310 [<00003173cc756f0c>] handle_pte_fault+0x4fc/0x760 [<00003173cc759212>] __handle_mm_fault+0x452/0xa00 [<00003173cc7599ba>] handle_mm_fault+0x1fa/0x6a0 [<00003173cc73409a>] __get_user_pages+0x4aa/0xba0 [<00003173cc7349e8>] get_user_pages_remote+0x258/0x770 [<000031734be6f052>] get_map_page+0xe2/0x190 [kvm] [<000031734be6f910>] adapter_indicators_set+0x50/0x4a0 [kvm] [<000031734be7f674>] set_adapter_int+0xc4/0x170 [kvm] [<000031734be2f268>] kvm_set_irq+0x228/0x3f0 [kvm] [<000031734be27000>] irqfd_inject+0xd0/0x150 [kvm] [<00003173cc00c9ec>] process_one_work+0x87c/0x1490 [<00003173cc00dda6>] worker_thread+0x7a6/0x1010 [<00003173cc02dc36>] kthread+0x3b6/0x710 [<00003173cbed2f0c>] __ret_from_fork+0xdc/0x7f0 [<00003173cdd737ca>] ret_from_fork+0xa/0x30 3 locks held by kworker/6:2/549: #0: 00000000800bc958 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7ee/0x1490 #1: 000030f3d527fbd0 ((work_completion)(&irqfd->inject)){+.+.}-{0:0}, at: process_one_work+0x81c/0x1490 #2: 00000000f99862b0 (&mm->mmap_lock){++++}-{3:3}, at: get_map_page+0xa8/0x190 [kvm] The "FAULT_FLAG_ALLOW_RETRY missing" indicates that handle_userfaultfd() saw a page fault request without ALLOW_RETRY flag set, hence userfaultfd cannot remotely resolve it (because the caller was asking for an immediate resolution, aka, FAULT_FLAG_NOWAIT, while remote faults can take time). With that, get_map_page() failed and the irq was lost. We should not be strictly in an atomic environment here and the worker should be sleepable (the call is done during an ioctl from userspace), so we can allow adapter_indicators_set() to just sleep waiting for the remote fault instead. Link: https://issues.redhat.com/browse/RHEL-42486 Signed-off-by: Peter Xu <peterx@redhat.com> [thuth: Assembled patch description and fixed some cosmetical issues] Signed-off-by: Thomas Huth <thuth@redhat.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Acked-by: Janosch Frank <frankja@linux.ibm.com> Fixes: f654706 ("KVM: s390/interrupt: do not pin adapter interrupt pages") [frankja: Added fixes tag] Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
kdave
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syzkaller has caught us red-handed once more, this time nesting regular
spinlocks behind raw spinlocks:
=============================
[ BUG: Invalid wait context ]
6.16.0-rc3-syzkaller-g7b8346bd9fce #0 Not tainted
-----------------------------
syz.0.29/3743 is trying to lock:
a3ff80008e2e9e18 (&xa->xa_lock#20){....}-{3:3}, at: vgic_put_irq+0xb4/0x190 arch/arm64/kvm/vgic/vgic.c:137
other info that might help us debug this:
context-{5:5}
3 locks held by syz.0.29/3743:
#0: a3ff80008e2e90a8 (&kvm->slots_lock){+.+.}-{4:4}, at: kvm_vgic_destroy+0x50/0x624 arch/arm64/kvm/vgic/vgic-init.c:499
#1: a3ff80008e2e9fa0 (&kvm->arch.config_lock){+.+.}-{4:4}, at: kvm_vgic_destroy+0x5c/0x624 arch/arm64/kvm/vgic/vgic-init.c:500
#2: 58f0000021be1428 (&vgic_cpu->ap_list_lock){....}-{2:2}, at: vgic_flush_pending_lpis+0x3c/0x31c arch/arm64/kvm/vgic/vgic.c:150
stack backtrace:
CPU: 0 UID: 0 PID: 3743 Comm: syz.0.29 Not tainted 6.16.0-rc3-syzkaller-g7b8346bd9fce #0 PREEMPT
Hardware name: linux,dummy-virt (DT)
Call trace:
show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:466 (C)
__dump_stack+0x30/0x40 lib/dump_stack.c:94
dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120
dump_stack+0x1c/0x28 lib/dump_stack.c:129
print_lock_invalid_wait_context kernel/locking/lockdep.c:4833 [inline]
check_wait_context kernel/locking/lockdep.c:4905 [inline]
__lock_acquire+0x978/0x299c kernel/locking/lockdep.c:5190
lock_acquire+0x14c/0x2e0 kernel/locking/lockdep.c:5871
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x5c/0x7c kernel/locking/spinlock.c:162
vgic_put_irq+0xb4/0x190 arch/arm64/kvm/vgic/vgic.c:137
vgic_flush_pending_lpis+0x24c/0x31c arch/arm64/kvm/vgic/vgic.c:158
__kvm_vgic_vcpu_destroy+0x44/0x500 arch/arm64/kvm/vgic/vgic-init.c:455
kvm_vgic_destroy+0x100/0x624 arch/arm64/kvm/vgic/vgic-init.c:505
kvm_arch_destroy_vm+0x80/0x138 arch/arm64/kvm/arm.c:244
kvm_destroy_vm virt/kvm/kvm_main.c:1308 [inline]
kvm_put_kvm+0x800/0xff8 virt/kvm/kvm_main.c:1344
kvm_vm_release+0x58/0x78 virt/kvm/kvm_main.c:1367
__fput+0x4ac/0x980 fs/file_table.c:465
____fput+0x20/0x58 fs/file_table.c:493
task_work_run+0x1bc/0x254 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
do_notify_resume+0x1b4/0x270 arch/arm64/kernel/entry-common.c:151
exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:169 [inline]
exit_to_user_mode arch/arm64/kernel/entry-common.c:178 [inline]
el0_svc+0xb4/0x160 arch/arm64/kernel/entry-common.c:768
el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786
el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600
This is of course no good, but is at odds with how LPI refcounts are
managed. Solve the locking mess by deferring the release of unreferenced
LPIs after the ap_list_lock is released. Mark these to-be-released LPIs
specially to avoid racing with vgic_put_irq() and causing a double-free.
Since references can only be taken on LPIs with a nonzero refcount,
extending the lifetime of freed LPIs is still safe.
Reviewed-by: Marc Zyngier <maz@kernel.org>
Reported-by: syzbot+cef594105ac7e60c6d93@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/kvmarm/68acd0d9.a00a0220.33401d.048b.GAE@google.com/
Link: https://lore.kernel.org/r/20250905100531.282980-5-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
kdave
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This attemps to fix possible UAFs caused by struct mgmt_pending being freed while still being processed like in the following trace, in order to fix mgmt_pending_valid is introduce and use to check if the mgmt_pending hasn't been removed from the pending list, on the complete callbacks it is used to check and in addtion remove the cmd from the list while holding mgmt_pending_lock to avoid TOCTOU problems since if the cmd is left on the list it can still be accessed and freed. BUG: KASAN: slab-use-after-free in mgmt_add_adv_patterns_monitor_sync+0x35/0x50 net/bluetooth/mgmt.c:5223 Read of size 8 at addr ffff8880709d4dc0 by task kworker/u11:0/55 CPU: 0 UID: 0 PID: 55 Comm: kworker/u11:0 Not tainted 6.16.4 #2 PREEMPT(full) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 Workqueue: hci0 hci_cmd_sync_work Call Trace: <TASK> dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 mgmt_add_adv_patterns_monitor_sync+0x35/0x50 net/bluetooth/mgmt.c:5223 hci_cmd_sync_work+0x210/0x3a0 net/bluetooth/hci_sync.c:332 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 home/kwqcheii/source/fuzzing/kernel/kasan/linux-6.16.4/arch/x86/entry/entry_64.S:245 </TASK> Allocated by task 12210: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4364 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] mgmt_pending_new+0x65/0x1e0 net/bluetooth/mgmt_util.c:269 mgmt_pending_add+0x35/0x140 net/bluetooth/mgmt_util.c:296 __add_adv_patterns_monitor+0x130/0x200 net/bluetooth/mgmt.c:5247 add_adv_patterns_monitor+0x214/0x360 net/bluetooth/mgmt.c:5364 hci_mgmt_cmd+0x9c9/0xef0 net/bluetooth/hci_sock.c:1719 hci_sock_sendmsg+0x6ca/0xef0 net/bluetooth/hci_sock.c:1839 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:729 sock_write_iter+0x258/0x330 net/socket.c:1133 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x5c9/0xb30 fs/read_write.c:686 ksys_write+0x145/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 12221: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2381 [inline] slab_free mm/slub.c:4648 [inline] kfree+0x18e/0x440 mm/slub.c:4847 mgmt_pending_free net/bluetooth/mgmt_util.c:311 [inline] mgmt_pending_foreach+0x30d/0x380 net/bluetooth/mgmt_util.c:257 __mgmt_power_off+0x169/0x350 net/bluetooth/mgmt.c:9444 hci_dev_close_sync+0x754/0x1330 net/bluetooth/hci_sync.c:5290 hci_dev_do_close net/bluetooth/hci_core.c:501 [inline] hci_dev_close+0x108/0x200 net/bluetooth/hci_core.c:526 sock_do_ioctl+0xd9/0x300 net/socket.c:1192 sock_ioctl+0x576/0x790 net/socket.c:1313 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Fixes: cf75ad8 ("Bluetooth: hci_sync: Convert MGMT_SET_POWERED") Fixes: 2bd1b23 ("Bluetooth: hci_sync: Convert MGMT_OP_SET_DISCOVERABLE to use cmd_sync") Fixes: f056a65 ("Bluetooth: hci_sync: Convert MGMT_OP_SET_CONNECTABLE to use cmd_sync") Fixes: 3244845 ("Bluetooth: hci_sync: Convert MGMT_OP_SSP") Fixes: d81a494 ("Bluetooth: hci_sync: Convert MGMT_OP_SET_LE") Fixes: b338d91 ("Bluetooth: Implement support for Mesh") Fixes: 6f6ff38 ("Bluetooth: hci_sync: Convert MGMT_OP_SET_LOCAL_NAME") Fixes: 71efbb0 ("Bluetooth: hci_sync: Convert MGMT_OP_SET_PHY_CONFIGURATION") Fixes: b747a83 ("Bluetooth: hci_sync: Refactor add Adv Monitor") Fixes: abfeea4 ("Bluetooth: hci_sync: Convert MGMT_OP_START_DISCOVERY") Fixes: 26ac4c5 ("Bluetooth: hci_sync: Convert MGMT_OP_SET_ADVERTISING") Reported-by: cen zhang <zzzccc427@gmail.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
kdave
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Ido Schimmel says: ==================== nexthop: Various fixes Patch #1 fixes a NPD that was recently reported by syzbot. Patch #2 fixes an issue in the existing FIB nexthop selftest. Patch #3 extends the selftest with test cases for the bug that was fixed in the first patch. ==================== Link: https://patch.msgid.link/20250921150824.149157-1-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
kdave
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Leon Hwang says: ==================== bpf: Allow union argument in trampoline based programs While tracing 'release_pages' with bpfsnoop[0], the verifier reports: The function release_pages arg0 type UNION is unsupported. However, it should be acceptable to trace functions that have 'union' arguments. This patch set enables such support in the verifier by allowing 'union' as a valid argument type. Changes: v3 -> v4: * Address comments from Alexei: * Trim bpftrace output in patch #1 log. * Drop the referenced commit info and the test output in patch #2 log. v2 -> v3: * Address comments from Alexei: * Reuse the existing flag BTF_FMODEL_STRUCT_ARG. * Update the comment of the flag BTF_FMODEL_STRUCT_ARG. v1 -> v2: * Add 16B 'union' argument support in x86_64 trampoline. * Update selftests using bpf_testmod. * Add test case about 16-bytes 'union' argument. * Address comments from Alexei: * Study the patch set about 'struct' argument support. * Update selftests to cover more cases. v1: https://lore.kernel.org/bpf/20250905133226.84675-1-leon.hwang@linux.dev/ Links: [0] https://github.com/bpfsnoop/bpfsnoop ==================== Link: https://patch.msgid.link/20250919044110.23729-1-leon.hwang@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org>
kdave
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The test starts a workload and then opens events. If the events fail
to open, for example because of perf_event_paranoid, the gopipe of the
workload is leaked and the file descriptor leak check fails when the
test exits. To avoid this cancel the workload when opening the events
fails.
Before:
```
$ perf test -vv 7
7: PERF_RECORD_* events & perf_sample fields:
--- start ---
test child forked, pid 1189568
Using CPUID GenuineIntel-6-B7-1
------------------------------------------------------------
perf_event_attr:
type 0 (PERF_TYPE_HARDWARE)
config 0xa00000000 (cpu_atom/PERF_COUNT_HW_CPU_CYCLES/)
disabled 1
------------------------------------------------------------
sys_perf_event_open: pid 0 cpu -1 group_fd -1 flags 0x8
sys_perf_event_open failed, error -13
------------------------------------------------------------
perf_event_attr:
type 0 (PERF_TYPE_HARDWARE)
config 0xa00000000 (cpu_atom/PERF_COUNT_HW_CPU_CYCLES/)
disabled 1
exclude_kernel 1
------------------------------------------------------------
sys_perf_event_open: pid 0 cpu -1 group_fd -1 flags 0x8 = 3
------------------------------------------------------------
perf_event_attr:
type 0 (PERF_TYPE_HARDWARE)
config 0x400000000 (cpu_core/PERF_COUNT_HW_CPU_CYCLES/)
disabled 1
------------------------------------------------------------
sys_perf_event_open: pid 0 cpu -1 group_fd -1 flags 0x8
sys_perf_event_open failed, error -13
------------------------------------------------------------
perf_event_attr:
type 0 (PERF_TYPE_HARDWARE)
config 0x400000000 (cpu_core/PERF_COUNT_HW_CPU_CYCLES/)
disabled 1
exclude_kernel 1
------------------------------------------------------------
sys_perf_event_open: pid 0 cpu -1 group_fd -1 flags 0x8 = 3
Attempt to add: software/cpu-clock/
..after resolving event: software/config=0/
cpu-clock -> software/cpu-clock/
------------------------------------------------------------
perf_event_attr:
type 1 (PERF_TYPE_SOFTWARE)
size 136
config 0x9 (PERF_COUNT_SW_DUMMY)
sample_type IP|TID|TIME|CPU
read_format ID|LOST
disabled 1
inherit 1
mmap 1
comm 1
enable_on_exec 1
task 1
sample_id_all 1
mmap2 1
comm_exec 1
ksymbol 1
bpf_event 1
{ wakeup_events, wakeup_watermark } 1
------------------------------------------------------------
sys_perf_event_open: pid 1189569 cpu 0 group_fd -1 flags 0x8
sys_perf_event_open failed, error -13
perf_evlist__open: Permission denied
---- end(-2) ----
Leak of file descriptor 6 that opened: 'pipe:[14200347]'
---- unexpected signal (6) ----
iFailed to read build ID for //anon
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#0 0x565358f6666e in child_test_sig_handler builtin-test.c:311
#1 0x7f29ce849df0 in __restore_rt libc_sigaction.c:0
#2 0x7f29ce89e95c in __pthread_kill_implementation pthread_kill.c:44
#3 0x7f29ce849cc2 in raise raise.c:27
#4 0x7f29ce8324ac in abort abort.c:81
#5 0x565358f662d4 in check_leaks builtin-test.c:226
#6 0x565358f6682e in run_test_child builtin-test.c:344
#7 0x565358ef7121 in start_command run-command.c:128
#8 0x565358f67273 in start_test builtin-test.c:545
#9 0x565358f6771d in __cmd_test builtin-test.c:647
#10 0x565358f682bd in cmd_test builtin-test.c:849
torvalds#11 0x565358ee5ded in run_builtin perf.c:349
torvalds#12 0x565358ee6085 in handle_internal_command perf.c:401
torvalds#13 0x565358ee61de in run_argv perf.c:448
torvalds#14 0x565358ee6527 in main perf.c:555
torvalds#15 0x7f29ce833ca8 in __libc_start_call_main libc_start_call_main.h:74
torvalds#16 0x7f29ce833d65 in __libc_start_main@@GLIBC_2.34 libc-start.c:128
torvalds#17 0x565358e391c1 in _start perf[851c1]
7: PERF_RECORD_* events & perf_sample fields : FAILED!
```
After:
```
$ perf test 7
7: PERF_RECORD_* events & perf_sample fields : Skip (permissions)
```
Fixes: 16d00fe ("perf tests: Move test__PERF_RECORD into separate object")
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.ibm.com>
Cc: Chun-Tse Shao <ctshao@google.com>
Cc: Howard Chu <howardchu95@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
kdave
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Oct 13, 2025
Check for an invalid length during LAUNCH_UPDATE at the start of snp_launch_update() instead of subtly relying on kvm_gmem_populate() to detect the bad state. Code that directly handles userspace input absolutely should sanitize those inputs; failure to do so is asking for bugs where KVM consumes an invalid "npages". Keep the check in gmem, but wrap it in a WARN to flag any bad usage by the caller. Note, this is technically an ABI change as KVM would previously allow a length of '0'. But allowing a length of '0' is nonsensical and creates pointless conundrums in KVM. E.g. an empty range is arguably neither private nor shared, but LAUNCH_UPDATE will fail if the starting gpa can't be made private. In practice, no known or well-behaved VMM passes a length of '0'. Note #2, the PAGE_ALIGNED(params.len) check ensures that lengths between 1 and 4095 (inclusive) are also rejected, i.e. that KVM won't end up with npages=0 when doing "npages = params.len / PAGE_SIZE". Cc: Thomas Lendacky <thomas.lendacky@amd.com> Cc: Michael Roth <michael.roth@amd.com> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lore.kernel.org/r/20250919211649.1575654-1-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
kdave
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Oct 13, 2025
Don't emulate branch instructions, e.g. CALL/RET/JMP etc., that are affected by Shadow Stacks and/or Indirect Branch Tracking when said features are enabled in the guest, as fully emulating CET would require significant complexity for no practical benefit (KVM shouldn't need to emulate branch instructions on modern hosts). Simply doing nothing isn't an option as that would allow a malicious entity to subvert CET protections via the emulator. To detect instructions that are subject to IBT or affect IBT state, use the existing IsBranch flag along with the source operand type to detect indirect branches, and the existing NearBranch flag to detect far JMPs and CALLs, all of which are effectively indirect. Explicitly check for emulation of IRET, FAR RET (IMM), and SYSEXIT (the ret-like far branches) instead of adding another flag, e.g. IsRet, as it's unlikely the emulator will ever need to check for return-like instructions outside of this one specific flow. Use an allow-list instead of a deny-list because (a) it's a shorter list and (b) so that a missed entry gets a false positive, not a false negative (i.e. reject emulation instead of clobbering CET state). For Shadow Stacks, explicitly track instructions that directly affect the current SSP, as KVM's emulator doesn't have existing flags that can be used to precisely detect such instructions. Alternatively, the em_xxx() helpers could directly check for ShadowStack interactions, but using a dedicated flag is arguably easier to audit, and allows for handling both IBT and SHSTK in one fell swoop. Note! On far transfers, do NOT consult the current privilege level and instead treat SHSTK/IBT as being enabled if they're enabled for User *or* Supervisor mode. On inter-privilege level far transfers, SHSTK and IBT can be in play for the target privilege level, i.e. checking the current privilege could get a false negative, and KVM doesn't know the target privilege level until emulation gets under way. Note #2, FAR JMP from 64-bit mode to compatibility mode interacts with the current SSP, but only to ensure SSP[63:32] == 0. Don't tag FAR JMP as SHSTK, which would be rather confusing and would result in FAR JMP being rejected unnecessarily the vast majority of the time (ignoring that it's unlikely to ever be emulated). A future commit will add the #GP(0) check for the specific FAR JMP scenario. Note #3, task switches also modify SSP and so need to be rejected. That too will be addressed in a future commit. Suggested-by: Chao Gao <chao.gao@intel.com> Originally-by: Yang Weijiang <weijiang.yang@intel.com> Cc: Mathias Krause <minipli@grsecurity.net> Cc: John Allen <john.allen@amd.com> Cc: Rick Edgecombe <rick.p.edgecombe@intel.com> Reviewed-by: Chao Gao <chao.gao@intel.com> Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Link: https://lore.kernel.org/r/20250919223258.1604852-19-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
kdave
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Oct 13, 2025
Before disabling SR-IOV via config space accesses to the parent PF, sriov_disable() first removes the PCI devices representing the VFs. Since commit 9d16947 ("PCI: Add global pci_lock_rescan_remove()") such removal operations are serialized against concurrent remove and rescan using the pci_rescan_remove_lock. No such locking was ever added in sriov_disable() however. In particular when commit 18f9e9d ("PCI/IOV: Factor out sriov_add_vfs()") factored out the PCI device removal into sriov_del_vfs() there was still no locking around the pci_iov_remove_virtfn() calls. On s390 the lack of serialization in sriov_disable() may cause double remove and list corruption with the below (amended) trace being observed: PSW: 0704c00180000000 0000000c914e4b38 (klist_put+56) GPRS: 000003800313fb48 0000000000000000 0000000100000001 0000000000000001 00000000f9b520a8 0000000000000000 0000000000002fbd 00000000f4cc9480 0000000000000001 0000000000000000 0000000000000000 0000000180692828 00000000818e8000 000003800313fe2c 000003800313fb20 000003800313fad8 #0 [3800313fb20] device_del at c9158ad5c #1 [3800313fb88] pci_remove_bus_device at c915105ba #2 [3800313fbd0] pci_iov_remove_virtfn at c9152f198 #3 [3800313fc28] zpci_iov_remove_virtfn at c90fb67c0 #4 [3800313fc60] zpci_bus_remove_device at c90fb6104 #5 [3800313fca0] __zpci_event_availability at c90fb3dca #6 [3800313fd08] chsc_process_sei_nt0 at c918fe4a2 #7 [3800313fd60] crw_collect_info at c91905822 #8 [3800313fe10] kthread at c90feb390 #9 [3800313fe68] __ret_from_fork at c90f6aa64 #10 [3800313fe98] ret_from_fork at c9194f3f2. This is because in addition to sriov_disable() removing the VFs, the platform also generates hot-unplug events for the VFs. This being the reverse operation to the hotplug events generated by sriov_enable() and handled via pdev->no_vf_scan. And while the event processing takes pci_rescan_remove_lock and checks whether the struct pci_dev still exists, the lack of synchronization makes this checking racy. Other races may also be possible of course though given that this lack of locking persisted so long observable races seem very rare. Even on s390 the list corruption was only observed with certain devices since the platform events are only triggered by config accesses after the removal, so as long as the removal finished synchronously they would not race. Either way the locking is missing so fix this by adding it to the sriov_del_vfs() helper. Just like PCI rescan-remove, locking is also missing in sriov_add_vfs() including for the error case where pci_stop_and_remove_bus_device() is called without the PCI rescan-remove lock being held. Even in the non-error case, adding new PCI devices and buses should be serialized via the PCI rescan-remove lock. Add the necessary locking. Fixes: 18f9e9d ("PCI/IOV: Factor out sriov_add_vfs()") Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Reviewed-by: Farhan Ali <alifm@linux.ibm.com> Reviewed-by: Julian Ruess <julianr@linux.ibm.com> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20250826-pci_fix_sriov_disable-v1-1-2d0bc938f2a3@linux.ibm.com
kdave
pushed a commit
that referenced
this pull request
Oct 16, 2025
Since blamed commit, unregister_netdevice_many_notify() takes the netdev
mutex if the device needs it.
If the device list is too long, this will lock more device mutexes than
lockdep can handle:
unshare -n \
bash -c 'for i in $(seq 1 100);do ip link add foo$i type dummy;done'
BUG: MAX_LOCK_DEPTH too low!
turning off the locking correctness validator.
depth: 48 max: 48!
48 locks held by kworker/u16:1/69:
#0: ..148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work
#1: ..d40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work
#2: ..bd0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net
#3: ..aa8 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch
#4: ..cb0 (&dev_instance_lock_key#3){+.+.}-{4:4}, at: unregister_netdevice_many_notify
[..]
Add a helper to close and then unlock a list of net_devices.
Devices that are not up have to be skipped - netif_close_many always
removes them from the list without any other actions taken, so they'd
remain in locked state.
Close devices whenever we've used up half of the tracking slots or we
processed entire list without hitting the limit.
Fixes: 7e4d784 ("net: hold netdev instance lock during rtnetlink operations")
Signed-off-by: Florian Westphal <fw@strlen.de>
Link: https://patch.msgid.link/20251013185052.14021-1-fw@strlen.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
kdave
pushed a commit
that referenced
this pull request
Oct 20, 2025
Expand the prefault memory selftest to add a regression test for a KVM bug where KVM's retry logic would result in (breakable) deadlock due to the memslot deletion waiting on prefaulting to release SRCU, and prefaulting waiting on the memslot to fully disappear (KVM uses a two-step process to delete memslots, and KVM x86 retries page faults if a to-be-deleted, a.k.a. INVALID, memslot is encountered). To exercise concurrent memslot remove, spawn a second thread to initiate memslot removal at roughly the same time as prefaulting. Test memslot removal for all testcases, i.e. don't limit concurrent removal to only the success case. There are essentially three prefault scenarios (so far) that are of interest: 1. Success 2. ENOENT due to no memslot 3. EAGAIN due to INVALID memslot For all intents and purposes, #1 and #2 are mutually exclusive, or rather, easier to test via separate testcases since writing to non-existent memory is trivial. But for #3, making it mutually exclusive with #1 _or_ #2 is actually more complex than testing memslot removal for all scenarios. The only requirement to let memslot removal coexist with other scenarios is a way to guarantee a stable result, e.g. that the "no memslot" test observes ENOENT, not EAGAIN, for the final checks. So, rather than make memslot removal mutually exclusive with the ENOENT scenario, simply restore the memslot and retry prefaulting. For the "no memslot" case, KVM_PRE_FAULT_MEMORY should be idempotent, i.e. should always fail with ENOENT regardless of how many times userspace attempts prefaulting. Pass in both the base GPA and the offset (instead of the "full" GPA) so that the worker can recreate the memslot. Signed-off-by: Yan Zhao <yan.y.zhao@intel.com> Co-developed-by: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/r/20250924174255.2141847-1-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
kdave
pushed a commit
that referenced
this pull request
Oct 27, 2025
The original code causes a circular locking dependency found by lockdep. ====================================================== WARNING: possible circular locking dependency detected 6.16.0-rc6-lgci-xe-xe-pw-151626v3+ #1 Tainted: G S U ------------------------------------------------------ xe_fault_inject/5091 is trying to acquire lock: ffff888156815688 ((work_completion)(&(&devcd->del_wk)->work)){+.+.}-{0:0}, at: __flush_work+0x25d/0x660 but task is already holding lock: ffff888156815620 (&devcd->mutex){+.+.}-{3:3}, at: dev_coredump_put+0x3f/0xa0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&devcd->mutex){+.+.}-{3:3}: mutex_lock_nested+0x4e/0xc0 devcd_data_write+0x27/0x90 sysfs_kf_bin_write+0x80/0xf0 kernfs_fop_write_iter+0x169/0x220 vfs_write+0x293/0x560 ksys_write+0x72/0xf0 __x64_sys_write+0x19/0x30 x64_sys_call+0x2bf/0x2660 do_syscall_64+0x93/0xb60 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #1 (kn->active#236){++++}-{0:0}: kernfs_drain+0x1e2/0x200 __kernfs_remove+0xae/0x400 kernfs_remove_by_name_ns+0x5d/0xc0 remove_files+0x54/0x70 sysfs_remove_group+0x3d/0xa0 sysfs_remove_groups+0x2e/0x60 device_remove_attrs+0xc7/0x100 device_del+0x15d/0x3b0 devcd_del+0x19/0x30 process_one_work+0x22b/0x6f0 worker_thread+0x1e8/0x3d0 kthread+0x11c/0x250 ret_from_fork+0x26c/0x2e0 ret_from_fork_asm+0x1a/0x30 -> #0 ((work_completion)(&(&devcd->del_wk)->work)){+.+.}-{0:0}: __lock_acquire+0x1661/0x2860 lock_acquire+0xc4/0x2f0 __flush_work+0x27a/0x660 flush_delayed_work+0x5d/0xa0 dev_coredump_put+0x63/0xa0 xe_driver_devcoredump_fini+0x12/0x20 [xe] devm_action_release+0x12/0x30 release_nodes+0x3a/0x120 devres_release_all+0x8a/0xd0 device_unbind_cleanup+0x12/0x80 device_release_driver_internal+0x23a/0x280 device_driver_detach+0x14/0x20 unbind_store+0xaf/0xc0 drv_attr_store+0x21/0x50 sysfs_kf_write+0x4a/0x80 kernfs_fop_write_iter+0x169/0x220 vfs_write+0x293/0x560 ksys_write+0x72/0xf0 __x64_sys_write+0x19/0x30 x64_sys_call+0x2bf/0x2660 do_syscall_64+0x93/0xb60 entry_SYSCALL_64_after_hwframe+0x76/0x7e other info that might help us debug this: Chain exists of: (work_completion)(&(&devcd->del_wk)->work) --> kn->active#236 --> &devcd->mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&devcd->mutex); lock(kn->active#236); lock(&devcd->mutex); lock((work_completion)(&(&devcd->del_wk)->work)); *** DEADLOCK *** 5 locks held by xe_fault_inject/5091: #0: ffff8881129f9488 (sb_writers#5){.+.+}-{0:0}, at: ksys_write+0x72/0xf0 #1: ffff88810c755078 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x123/0x220 #2: ffff8881054811a0 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0x55/0x280 #3: ffff888156815620 (&devcd->mutex){+.+.}-{3:3}, at: dev_coredump_put+0x3f/0xa0 #4: ffffffff8359e020 (rcu_read_lock){....}-{1:2}, at: __flush_work+0x72/0x660 stack backtrace: CPU: 14 UID: 0 PID: 5091 Comm: xe_fault_inject Tainted: G S U 6.16.0-rc6-lgci-xe-xe-pw-151626v3+ #1 PREEMPT_{RT,(lazy)} Tainted: [S]=CPU_OUT_OF_SPEC, [U]=USER Hardware name: Micro-Star International Co., Ltd. MS-7D25/PRO Z690-A DDR4(MS-7D25), BIOS 1.10 12/13/2021 Call Trace: <TASK> dump_stack_lvl+0x91/0xf0 dump_stack+0x10/0x20 print_circular_bug+0x285/0x360 check_noncircular+0x135/0x150 ? register_lock_class+0x48/0x4a0 __lock_acquire+0x1661/0x2860 lock_acquire+0xc4/0x2f0 ? __flush_work+0x25d/0x660 ? mark_held_locks+0x46/0x90 ? __flush_work+0x25d/0x660 __flush_work+0x27a/0x660 ? __flush_work+0x25d/0x660 ? trace_hardirqs_on+0x1e/0xd0 ? __pfx_wq_barrier_func+0x10/0x10 flush_delayed_work+0x5d/0xa0 dev_coredump_put+0x63/0xa0 xe_driver_devcoredump_fini+0x12/0x20 [xe] devm_action_release+0x12/0x30 release_nodes+0x3a/0x120 devres_release_all+0x8a/0xd0 device_unbind_cleanup+0x12/0x80 device_release_driver_internal+0x23a/0x280 ? bus_find_device+0xa8/0xe0 device_driver_detach+0x14/0x20 unbind_store+0xaf/0xc0 drv_attr_store+0x21/0x50 sysfs_kf_write+0x4a/0x80 kernfs_fop_write_iter+0x169/0x220 vfs_write+0x293/0x560 ksys_write+0x72/0xf0 __x64_sys_write+0x19/0x30 x64_sys_call+0x2bf/0x2660 do_syscall_64+0x93/0xb60 ? __f_unlock_pos+0x15/0x20 ? __x64_sys_getdents64+0x9b/0x130 ? __pfx_filldir64+0x10/0x10 ? do_syscall_64+0x1a2/0xb60 ? clear_bhb_loop+0x30/0x80 ? clear_bhb_loop+0x30/0x80 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x76e292edd574 Code: c7 00 16 00 00 00 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 80 3d d5 ea 0e 00 00 74 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 55 48 89 e5 48 83 ec 20 48 89 RSP: 002b:00007fffe247a828 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000076e292edd574 RDX: 000000000000000c RSI: 00006267f6306063 RDI: 000000000000000b RBP: 000000000000000c R08: 000076e292fc4b20 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00006267f6306063 R13: 000000000000000b R14: 00006267e6859c00 R15: 000076e29322a000 </TASK> xe 0000:03:00.0: [drm] Xe device coredump has been deleted. Fixes: 01daccf ("devcoredump : Serialize devcd_del work") Cc: Mukesh Ojha <quic_mojha@quicinc.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Rafael J. Wysocki <rafael@kernel.org> Cc: Danilo Krummrich <dakr@kernel.org> Cc: linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org # v6.1+ Signed-off-by: Maarten Lankhorst <dev@lankhorst.se> Cc: Matthew Brost <matthew.brost@intel.com> Acked-by: Mukesh Ojha <mukesh.ojha@oss.qualcomm.com> Link: https://lore.kernel.org/r/20250723142416.1020423-1-dev@lankhorst.se Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Please consider these fixes, in the area of handling devices and sysfs. Mainly they are bug fixes and framework changes. And towards the end of this patch set, I have two patches which are introducing two new features, device delete by devid and sysfs attributes for btrfs pool.
These patches were sent to mailing list before. Kindly note few of the subject are changed for good and to backtrack the old subject are maintained in the changelog. Also the review changes that some of the patches went through are also in the changelog, which probably should be deleted when merged. They are maintained their because there doesn't seems to be any option in github to track the same. Thanks, Anand