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Ilp32 5.2 #1

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Ilp32 5.2 #1

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Dave Martin and others added 23 commits July 9, 2019 13:14
…layout

ILP32 uses the same struct sigcontext as the native ABI (i.e.,
LP64), but a different layout for the rest of the signal frame (since
siginfo_t and ucontext_t are both ABI-dependent).

Since the purpose of parse_user_sigframe() is really to parse sigcontext
and not the whole signal frame, the function does not need to depend
on the layout of rt_sigframe -- the only purpose of the rt_sigframe
pointer is for use as a base to measure the signal frame size.

So, this patch renames the function to make it clear that only the
sigcontext is really being parsed, and makes the sigframe base pointer
generic.  A macro is defined to provide a suitable duck-typed interface
that can be used with both sigframe definitions.

Suggested-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Yury Norov <ynorov@marvell.com>
compat_ptrace_request() lacks handlers for PTRACE_{G,S}ETSIGMASK,
instead using those in ptrace_request(). The compat variant should
read a compat_sigset_t from userspace instead of ptrace_request()s
sigset_t.

While compat_sigset_t is the same size as sigset_t, it is defined as
2xu32, instead of a single u64. On a big-endian CPU this means that
compat_sigset_t is passed to user-space using middle-endianness,
where the least-significant u32 is written most significant byte
first.

If ptrace_request()s code is used userspace will read the most
significant u32 where it expected the least significant.

Instead of duplicating ptrace_request()s code as a special case in
the arch code, handle it here.

Fixes: 29000ca ("ptrace: add ability to get/set signal-blocked mask")
CC: Andrey Vagin <avagin@openvz.org>
Signed-off-by: James Morse <james.morse@arm.com>

Yury:
Replace sigset_{to,from}_compat() with new {get,put}_compat_sigset()
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Yury Norov <ynorov@marvell.com>
Thread bits may be accessed from low-level code, so isolating is a measure
to avoid circular dependencies in header files.

The exact reason for circular dependency is WARN_ON() macro added in patch
edd63a2 "set_restore_sigmask() is never called without SIGPENDING (and
never should be)"

Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Yury Norov <ynorov@marvell.com>
Based on Andrew Pinski's patch-series.

Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Yury Norov <ynorov@marvell.com>
In this patchset ILP32 ABI support is added. Additionally to AARCH32,
which is binary-compatible with ARM, ILP32 is (mostly) ABI-compatible.

From now, AARCH32_EL0 (former COMPAT) config option means the support of
AARCH32 userspace, and ARM64_ILP32 - support of ILP32 ABI (see following
patches). COMPAT indicates that one of them or both is enabled.

Where needed, CONFIG_COMPAT is changed over to use CONFIG_AARCH32_EL0
instead.

Reviewed-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Andrew Pinski <Andrew.Pinski@caviumnetworks.com>
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Signed-off-by: Christoph Muellner <christoph.muellner@theobroma-systems.com>
Signed-off-by: Bamvor Jian Zhang <bamv2005@gmail.com>
Signed-off-by: Yury Norov <ynorov@marvell.com>
The ILP32 for ARM64 patch series introduces another 'compat' mode additionally
to aarch32_el0. So to avoid confusing, aarch32-only functions renamed in
according to it.

Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Yury Norov <ynorov@marvell.com>
Define __BITS_PER_LONG depending on the ABI used (i.e. check whether
__ILP32__ or __LP64__ is defined).  This is necessary for glibc to
determine the appropriate type definitions for the system call interface.

Signed-off-by: Andrew Pinski <apinski@cavium.com>
Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Signed-off-by: Christoph Muellner <christoph.muellner@theobroma-systems.com>
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Reviewed-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Yury Norov <ynorov@marvell.com>
Based on patch of Andrew Pinski.

This patch introduces is_a32_compat_task and is_a32_thread so it is
easier to say this is a a32 specific thread or a generic compat
thread/task. Corresponding functions are located in <asm/is_compat.h>
to avoid mess in headers.

Some files include both <linux/compat.h> and <asm/compat.h>,
and this is wrong because <linux/compat.h> has <asm/compat.h> already
included. It was fixed too.

Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Andrew Pinski <Andrew.Pinski@caviumnetworks.com>
Signed-off-by: Bamvor Jian Zhang <bamv2005@gmail.com>
Signed-off-by: Yury Norov <ynorov@marvell.com>
ILP32 tasks are needed to be distinguished from LP64 and AARCH32.
This patch adds helper functions is_ilp32_compat_{task,thread} and
thread flag TIF_32BIT_AARCH64 to address it. This is a preparation
for following patches in ILP32 patchset.

For consistency, SET_PERSONALITY is changed here accordingly.

Signed-off-by: Andrew Pinski <Andrew.Pinski@caviumnetworks.com>
Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Signed-off-by: Christoph Muellner <christoph.muellner@theobroma-systems.com>
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Reviewed-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Yury Norov <ynorov@marvell.com>
syscall_get_arch() currently makes no difference between arm64 and
arm64/ilp32. Fix it by adding AUDIT_ARCH_AARCH64ILP32.

Reported-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Yury Norov <ynorov@marvell.com>
As we support more than one compat formats, it looks more reasonable
to not use fs/compat_binfmt.c. Custom binfmt_elf32.c allows to move aarch32
specific definitions there and make code more maintainable and readable.

Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Yury Norov <ynorov@marvell.com>
ILP32 patch series introduces new type of binaries which is also compat.
So rename existung aarch32 compat_elf_hwcap's helps to avoid confusing.

Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Yury Norov <ynorov@marvell.com>
Like binfmt_elf32.c for AARCH32, binfmt_ilp32.c is needed to handle
ILP32 binaries.

Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Bamvor Jian Zhang <bamv2005@gmail.com>
Signed-off-by: Yury Norov <ynorov@marvell.com>
According to userspace/kernel ABI, userspace off_t is  passed in register
pair just like in aarch32. In this patch corresponding aarch32 handlers
are shared to ilp32 code.

Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Yury Norov <ynorov@marvell.com>
Depending on the personality of the task, syscalls has to be dispatched
to either aarch64, aarch32 or aarch64/ilp32 syscall handlers. We add
the support of ILP32 mode in this series, therefore introduce
corresponding syscall table.

Some system calls are wired to aarch32 syscall handlers, as listed in
arch/arm64/kernel/sys_ilp32.c.

For aarch64/ilp32, top halves of syscall arguments are meaningless
anthough not zeroed by hardware. Do that in the delouse_pt_regs()
routine to avoid passing garbage by userspace.

Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Yury Norov <ynorov@marvell.com>
Following patches of the series introduce ILP32-specific structures and
handlers for signal subsystem. In this patch, functions and structures
that common for LP64 and ILP32 are moved to
arch/arm64/include/asm/signal_common.h to let ILP32 code reuse them. Some
functions work with struct rt_sigframe which differs for ILP32. Therefore,
to let ILP32 generate correct code, body of that functions are moved to
arch/arm64/include/asm/signal_common.h. Others just declared in new header.

Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Yury Norov <ynorov@marvell.com>
ILP32 needs to mix 32bit struct siginfo and 64bit sigframe for its signal
handlers. Move the existing compat code for copying siginfo to user space
and manipulating signal masks into signal32_common.c so it can be used to
deliver aarch32 and ilp32 signals.

Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Yury Norov <ynorov@marvell.com>
ILP32 uses AARCH32 compat structures and syscall handlers for signals. But
ILP32 rt_sigframe and ucontext structures differ from both LP64 and AARCH32.
>From software point of view ILP32 is typical 32-bit compat ABI, and from
hardware point of view, it's just like LP64.

struct rt_sigframe defined in this patch in
arch/arm64/kernel/signal_ilp32.c redefines one in
arch/arm64/kernel/signal.c. And functions located in
arch/arm64/include/signal_common.h pick up new structure to generate the
code suitable for ILP32.

Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Yury Norov <ynorov@marvell.com>
ILP32 has context-related structures different from both aarch32 and
aarch64/lp64. In this patch compat_arch_ptrace() renamed to
compat_a32_ptrace(), and compat_arch_ptrace() only makes choice between
compat_a32_ptrace() and new compat_ilp32_ptrace() handler.

compat_ilp32_ptrace() calls generic compat_ptrace_request() for all
requests except PTRACE_GETSIGMASK and PTRACE_SETSIGMASK, which need
special handling.

Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Bamvor Jian Zhang <bamv2005@gmail.com>
Signed-off-by: Yury Norov <ynorov@marvell.com>
ILP32 VDSO exports following symbols:
 __kernel_rt_sigreturn;
 __kernel_gettimeofday;
 __kernel_clock_gettime;
 __kernel_clock_getres.

What shared object to use, kernel selects depending on result of
is_ilp32_compat_task() in arch/arm64/kernel/vdso.c, so it substitutes
correct pages and spec.

Adjusted to move the data page before code pages in sync with
commit 601255a ("arm64: vdso: move data page before code pages")

Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Signed-off-by: Christoph Muellner <christoph.muellner@theobroma-systems.com>
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Bamvor Jian Zhang <bamv2005@gmail.com>
Signed-off-by: Yury Norov <ynorov@marvell.com>
This patch adds the config option for ILP32.

Signed-off-by: Andrew Pinski <Andrew.Pinski@caviumnetworks.com>
Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Signed-off-by: Christoph Muellner <christoph.muellner@theobroma-systems.com>
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Reviewed-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Yury Norov <ynorov@marvell.com>
The intention of the ILP32 branches is to enable ILP32 by default. This
default is to be revisited for upstream merging.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Yury Norov <ynorov@marvell.com>
Depending on the type of compat execution (aarch32 or ilp32), we should wire
some syscalls to different numbers in order to make seccomp work correctly.

The implementation idea is borrowed from MIPS code.

Signed-off-by: Yury Norov <yury.norov@gmail.com>
Reported-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
@viordash viordash closed this Oct 30, 2024
norov pushed a commit that referenced this pull request Nov 14, 2024
Currently, when configuring TMU (Time Management Unit) mode of a given
router, we take into account only its own TMU requirements ignoring
other routers in the domain. This is problematic if the router we are
configuring has lower TMU requirements than what is already configured
in the domain.

In the scenario below, we have a host router with two USB4 ports: A and
B. Port A connected to device router #1 (which supports CL states) and
existing DisplayPort tunnel, thus, the TMU mode is HiFi uni-directional.

1. Initial topology

          [Host]
         A/
         /
 [Device #1]
   /
Monitor

2. Plug in device #2 (that supports CL states) to downstream port B of
   the host router

         [Host]
        A/    B\
        /       \
 [Device #1]    [Device #2]
   /
Monitor

The TMU mode on port B and port A will be configured to LowRes which is
not what we want and will cause monitor to start flickering.

To address this we first scan the domain and search for any router
configured to HiFi uni-directional mode, and if found, configure TMU
mode of the given router to HiFi uni-directional as well.

Cc: stable@vger.kernel.org
Signed-off-by: Gil Fine <gil.fine@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
norov pushed a commit that referenced this pull request Nov 14, 2024
The variable wwan_rtnl_link_ops assign a *bigger* maxtype which leads to
a global out-of-bounds read when parsing the netlink attributes. Exactly
same bug cause as the oob fixed in commit b33fb5b ("net: qualcomm:
rmnet: fix global oob in rmnet_policy").

==================================================================
BUG: KASAN: global-out-of-bounds in validate_nla lib/nlattr.c:388 [inline]
BUG: KASAN: global-out-of-bounds in __nla_validate_parse+0x19d7/0x29a0 lib/nlattr.c:603
Read of size 1 at addr ffffffff8b09cb60 by task syz.1.66276/323862

CPU: 0 PID: 323862 Comm: syz.1.66276 Not tainted 6.1.70 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x177/0x231 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:284 [inline]
 print_report+0x14f/0x750 mm/kasan/report.c:395
 kasan_report+0x139/0x170 mm/kasan/report.c:495
 validate_nla lib/nlattr.c:388 [inline]
 __nla_validate_parse+0x19d7/0x29a0 lib/nlattr.c:603
 __nla_parse+0x3c/0x50 lib/nlattr.c:700
 nla_parse_nested_deprecated include/net/netlink.h:1269 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3514 [inline]
 rtnl_newlink+0x7bc/0x1fd0 net/core/rtnetlink.c:3623
 rtnetlink_rcv_msg+0x794/0xef0 net/core/rtnetlink.c:6122
 netlink_rcv_skb+0x1de/0x420 net/netlink/af_netlink.c:2508
 netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline]
 netlink_unicast+0x74b/0x8c0 net/netlink/af_netlink.c:1352
 netlink_sendmsg+0x882/0xb90 net/netlink/af_netlink.c:1874
 sock_sendmsg_nosec net/socket.c:716 [inline]
 __sock_sendmsg net/socket.c:728 [inline]
 ____sys_sendmsg+0x5cc/0x8f0 net/socket.c:2499
 ___sys_sendmsg+0x21c/0x290 net/socket.c:2553
 __sys_sendmsg net/socket.c:2582 [inline]
 __do_sys_sendmsg net/socket.c:2591 [inline]
 __se_sys_sendmsg+0x19e/0x270 net/socket.c:2589
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x45/0x90 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f67b19a24ad
RSP: 002b:00007f67b17febb8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f67b1b45f80 RCX: 00007f67b19a24ad
RDX: 0000000000000000 RSI: 0000000020005e40 RDI: 0000000000000004
RBP: 00007f67b1a1e01d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd2513764f R14: 00007ffd251376e0 R15: 00007f67b17fed40
 </TASK>

The buggy address belongs to the variable:
 wwan_rtnl_policy+0x20/0x40

The buggy address belongs to the physical page:
page:ffffea00002c2700 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xb09c
flags: 0xfff00000001000(reserved|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000001000 ffffea00002c2708 ffffea00002c2708 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner info is not present (never set?)

Memory state around the buggy address:
 ffffffff8b09ca00: 05 f9 f9 f9 05 f9 f9 f9 00 01 f9 f9 00 01 f9 f9
 ffffffff8b09ca80: 00 00 00 05 f9 f9 f9 f9 00 00 03 f9 f9 f9 f9 f9
>ffffffff8b09cb00: 00 00 00 00 05 f9 f9 f9 00 00 00 00 f9 f9 f9 f9
                                                       ^
 ffffffff8b09cb80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================

According to the comment of `nla_parse_nested_deprecated`, use correct size
`IFLA_WWAN_MAX` here to fix this issue.

Fixes: 88b7105 ("wwan: add interface creation support")
Signed-off-by: Lin Ma <linma@zju.edu.cn>
Reviewed-by: Loic Poulain <loic.poulain@linaro.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20241015131621.47503-1-linma@zju.edu.cn
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
norov pushed a commit that referenced this pull request Nov 14, 2024
…n_net

In the normal case, when we excute `echo 0 > /proc/fs/nfsd/threads`, the
function `nfs4_state_destroy_net` in `nfs4_state_shutdown_net` will
release all resources related to the hashed `nfs4_client`. If the
`nfsd_client_shrinker` is running concurrently, the `expire_client`
function will first unhash this client and then destroy it. This can
lead to the following warning. Additionally, numerous use-after-free
errors may occur as well.

nfsd_client_shrinker         echo 0 > /proc/fs/nfsd/threads

expire_client                nfsd_shutdown_net
  unhash_client                ...
                               nfs4_state_shutdown_net
                                 /* won't wait shrinker exit */
  /*                             cancel_work(&nn->nfsd_shrinker_work)
   * nfsd_file for this          /* won't destroy unhashed client1 */
   * client1 still alive         nfs4_state_destroy_net
   */

                               nfsd_file_cache_shutdown
                                 /* trigger warning */
                                 kmem_cache_destroy(nfsd_file_slab)
                                 kmem_cache_destroy(nfsd_file_mark_slab)
  /* release nfsd_file and mark */
  __destroy_client

====================================================================
BUG nfsd_file (Not tainted): Objects remaining in nfsd_file on
__kmem_cache_shutdown()
--------------------------------------------------------------------
CPU: 4 UID: 0 PID: 764 Comm: sh Not tainted 6.12.0-rc3+ #1

 dump_stack_lvl+0x53/0x70
 slab_err+0xb0/0xf0
 __kmem_cache_shutdown+0x15c/0x310
 kmem_cache_destroy+0x66/0x160
 nfsd_file_cache_shutdown+0xac/0x210 [nfsd]
 nfsd_destroy_serv+0x251/0x2a0 [nfsd]
 nfsd_svc+0x125/0x1e0 [nfsd]
 write_threads+0x16a/0x2a0 [nfsd]
 nfsctl_transaction_write+0x74/0xa0 [nfsd]
 vfs_write+0x1a5/0x6d0
 ksys_write+0xc1/0x160
 do_syscall_64+0x5f/0x170
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

====================================================================
BUG nfsd_file_mark (Tainted: G    B   W         ): Objects remaining
nfsd_file_mark on __kmem_cache_shutdown()
--------------------------------------------------------------------

 dump_stack_lvl+0x53/0x70
 slab_err+0xb0/0xf0
 __kmem_cache_shutdown+0x15c/0x310
 kmem_cache_destroy+0x66/0x160
 nfsd_file_cache_shutdown+0xc8/0x210 [nfsd]
 nfsd_destroy_serv+0x251/0x2a0 [nfsd]
 nfsd_svc+0x125/0x1e0 [nfsd]
 write_threads+0x16a/0x2a0 [nfsd]
 nfsctl_transaction_write+0x74/0xa0 [nfsd]
 vfs_write+0x1a5/0x6d0
 ksys_write+0xc1/0x160
 do_syscall_64+0x5f/0x170
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

To resolve this issue, cancel `nfsd_shrinker_work` using synchronous
mode in nfs4_state_shutdown_net.

Fixes: 7c24fa2 ("NFSD: replace delayed_work with work_struct for nfsd_client_shrinker")
Signed-off-by: Yang Erkun <yangerkun@huaweicloud.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
norov pushed a commit that referenced this pull request Nov 14, 2024
The scmi_dev->name is released prematurely in __scmi_device_destroy(),
which causes slab-use-after-free when accessing scmi_dev->name in
scmi_bus_notifier(). So move the release of scmi_dev->name to
scmi_device_release() to avoid slab-use-after-free.

  |  BUG: KASAN: slab-use-after-free in strncmp+0xe4/0xec
  |  Read of size 1 at addr ffffff80a482bcc0 by task swapper/0/1
  |
  |  CPU: 1 PID: 1 Comm: swapper/0 Not tainted 6.6.38-debug #1
  |  Hardware name: Qualcomm Technologies, Inc. SA8775P Ride (DT)
  |  Call trace:
  |   dump_backtrace+0x94/0x114
  |   show_stack+0x18/0x24
  |   dump_stack_lvl+0x48/0x60
  |   print_report+0xf4/0x5b0
  |   kasan_report+0xa4/0xec
  |   __asan_report_load1_noabort+0x20/0x2c
  |   strncmp+0xe4/0xec
  |   scmi_bus_notifier+0x5c/0x54c
  |   notifier_call_chain+0xb4/0x31c
  |   blocking_notifier_call_chain+0x68/0x9c
  |   bus_notify+0x54/0x78
  |   device_del+0x1bc/0x840
  |   device_unregister+0x20/0xb4
  |   __scmi_device_destroy+0xac/0x280
  |   scmi_device_destroy+0x94/0xd0
  |   scmi_chan_setup+0x524/0x750
  |   scmi_probe+0x7fc/0x1508
  |   platform_probe+0xc4/0x19c
  |   really_probe+0x32c/0x99c
  |   __driver_probe_device+0x15c/0x3c4
  |   driver_probe_device+0x5c/0x170
  |   __driver_attach+0x1c8/0x440
  |   bus_for_each_dev+0xf4/0x178
  |   driver_attach+0x3c/0x58
  |   bus_add_driver+0x234/0x4d4
  |   driver_register+0xf4/0x3c0
  |   __platform_driver_register+0x60/0x88
  |   scmi_driver_init+0xb0/0x104
  |   do_one_initcall+0xb4/0x664
  |   kernel_init_freeable+0x3c8/0x894
  |   kernel_init+0x24/0x1e8
  |   ret_from_fork+0x10/0x20
  |
  |  Allocated by task 1:
  |   kasan_save_stack+0x2c/0x54
  |   kasan_set_track+0x2c/0x40
  |   kasan_save_alloc_info+0x24/0x34
  |   __kasan_kmalloc+0xa0/0xb8
  |   __kmalloc_node_track_caller+0x6c/0x104
  |   kstrdup+0x48/0x84
  |   kstrdup_const+0x34/0x40
  |   __scmi_device_create.part.0+0x8c/0x408
  |   scmi_device_create+0x104/0x370
  |   scmi_chan_setup+0x2a0/0x750
  |   scmi_probe+0x7fc/0x1508
  |   platform_probe+0xc4/0x19c
  |   really_probe+0x32c/0x99c
  |   __driver_probe_device+0x15c/0x3c4
  |   driver_probe_device+0x5c/0x170
  |   __driver_attach+0x1c8/0x440
  |   bus_for_each_dev+0xf4/0x178
  |   driver_attach+0x3c/0x58
  |   bus_add_driver+0x234/0x4d4
  |   driver_register+0xf4/0x3c0
  |   __platform_driver_register+0x60/0x88
  |   scmi_driver_init+0xb0/0x104
  |   do_one_initcall+0xb4/0x664
  |   kernel_init_freeable+0x3c8/0x894
  |   kernel_init+0x24/0x1e8
  |   ret_from_fork+0x10/0x20
  |
  |  Freed by task 1:
  |   kasan_save_stack+0x2c/0x54
  |   kasan_set_track+0x2c/0x40
  |   kasan_save_free_info+0x38/0x5c
  |   __kasan_slab_free+0xe8/0x164
  |   __kmem_cache_free+0x11c/0x230
  |   kfree+0x70/0x130
  |   kfree_const+0x20/0x40
  |   __scmi_device_destroy+0x70/0x280
  |   scmi_device_destroy+0x94/0xd0
  |   scmi_chan_setup+0x524/0x750
  |   scmi_probe+0x7fc/0x1508
  |   platform_probe+0xc4/0x19c
  |   really_probe+0x32c/0x99c
  |   __driver_probe_device+0x15c/0x3c4
  |   driver_probe_device+0x5c/0x170
  |   __driver_attach+0x1c8/0x440
  |   bus_for_each_dev+0xf4/0x178
  |   driver_attach+0x3c/0x58
  |   bus_add_driver+0x234/0x4d4
  |   driver_register+0xf4/0x3c0
  |   __platform_driver_register+0x60/0x88
  |   scmi_driver_init+0xb0/0x104
  |   do_one_initcall+0xb4/0x664
  |   kernel_init_freeable+0x3c8/0x894
  |   kernel_init+0x24/0x1e8
  |   ret_from_fork+0x10/0x20

Fixes: ee7a9c9 ("firmware: arm_scmi: Add support for multiple device per protocol")
Signed-off-by: Xinqi Zhang <quic_xinqzhan@quicinc.com>
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Reviewed-by: Bjorn Andersson <andersson@kernel.org>
Message-Id: <20241016-fix-arm-scmi-slab-use-after-free-v2-1-1783685ef90d@quicinc.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
norov pushed a commit that referenced this pull request Nov 14, 2024
[BUG]
Syzbot reports the following crash:

  BTRFS info (device loop0 state MCS): disabling free space tree
  BTRFS info (device loop0 state MCS): clearing compat-ro feature flag for FREE_SPACE_TREE (0x1)
  BTRFS info (device loop0 state MCS): clearing compat-ro feature flag for FREE_SPACE_TREE_VALID (0x2)
  Oops: general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN NOPTI
  KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f]
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
  RIP: 0010:backup_super_roots fs/btrfs/disk-io.c:1691 [inline]
  RIP: 0010:write_all_supers+0x97a/0x40f0 fs/btrfs/disk-io.c:4041
  Call Trace:
   <TASK>
   btrfs_commit_transaction+0x1eae/0x3740 fs/btrfs/transaction.c:2530
   btrfs_delete_free_space_tree+0x383/0x730 fs/btrfs/free-space-tree.c:1312
   btrfs_start_pre_rw_mount+0xf28/0x1300 fs/btrfs/disk-io.c:3012
   btrfs_remount_rw fs/btrfs/super.c:1309 [inline]
   btrfs_reconfigure+0xae6/0x2d40 fs/btrfs/super.c:1534
   btrfs_reconfigure_for_mount fs/btrfs/super.c:2020 [inline]
   btrfs_get_tree_subvol fs/btrfs/super.c:2079 [inline]
   btrfs_get_tree+0x918/0x1920 fs/btrfs/super.c:2115
   vfs_get_tree+0x90/0x2b0 fs/super.c:1800
   do_new_mount+0x2be/0xb40 fs/namespace.c:3472
   do_mount fs/namespace.c:3812 [inline]
   __do_sys_mount fs/namespace.c:4020 [inline]
   __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3997
   do_syscall_x64 arch/x86/entry/common.c:52 [inline]
   do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
   entry_SYSCALL_64_after_hwframe+0x77/0x7f

[CAUSE]
To support mounting different subvolume with different RO/RW flags for
the new mount APIs, btrfs introduced two workaround to support this feature:

- Skip mount option/feature checks if we are mounting a different
  subvolume

- Reconfigure the fs to RW if the initial mount is RO

Combining these two, we can have the following sequence:

- Mount the fs ro,rescue=all,clear_cache,space_cache=v1
  rescue=all will mark the fs as hard read-only, so no v2 cache clearing
  will happen.

- Mount a subvolume rw of the same fs.
  We go into btrfs_get_tree_subvol(), but fc_mount() returns EBUSY
  because our new fc is RW, different from the original fs.

  Now we enter btrfs_reconfigure_for_mount(), which switches the RO flag
  first so that we can grab the existing fs_info.
  Then we reconfigure the fs to RW.

- During reconfiguration, option/features check is skipped
  This means we will restart the v2 cache clearing, and convert back to
  v1 cache.
  This will trigger fs writes, and since the original fs has "rescue=all"
  option, it skips the csum tree read.

  And eventually causing NULL pointer dereference in super block
  writeback.

[FIX]
For reconfiguration caused by different subvolume RO/RW flags, ensure we
always run btrfs_check_options() to ensure we have proper hard RO
requirements met.

In fact the function btrfs_check_options() doesn't really do many
complex checks, but hard RO requirement and some feature dependency
checks, thus there is no special reason not to do the check for mount
reconfiguration.

Reported-by: syzbot+56360f93efa90ff15870@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/0000000000008c5d090621cb2770@google.com/
Fixes: f044b31 ("btrfs: handle the ro->rw transition for mounting different subvolumes")
CC: stable@vger.kernel.org # 6.8+
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
norov pushed a commit that referenced this pull request Nov 14, 2024
When creating a trace_probe we would set nr_args prior to truncating the
arguments to MAX_TRACE_ARGS. However, we would only initialize arguments
up to the limit.

This caused invalid memory access when attempting to set up probes with
more than 128 fetchargs.

  BUG: kernel NULL pointer dereference, address: 0000000000000020
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 0 P4D 0
  Oops: Oops: 0000 [#1] PREEMPT SMP PTI
  CPU: 0 UID: 0 PID: 1769 Comm: cat Not tainted 6.11.0-rc7+ torvalds#8
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-1.fc39 04/01/2014
  RIP: 0010:__set_print_fmt+0x134/0x330

Resolve the issue by applying the MAX_TRACE_ARGS limit earlier. Return
an error when there are too many arguments instead of silently
truncating.

Link: https://lore.kernel.org/all/20240930202656.292869-1-mikel@mikelr.com/

Fixes: 035ba76 ("tracing/probes: cleanup: Set trace_probe::nr_args at trace_probe_init")
Signed-off-by: Mikel Rychliski <mikel@mikelr.com>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
norov pushed a commit that referenced this pull request Jan 14, 2025
Blamed commit forgot MSG_PEEK case, allowing a crash [1] as found
by syzbot.

Rework vlan_get_tci() to not touch skb at all,
so that it can be used from many cpus on the same skb.

Add a const qualifier to skb argument.

[1]
skbuff: skb_under_panic: text:ffffffff8a8da482 len:32 put:14 head:ffff88807a1d5800 data:ffff88807a1d5810 tail:0x14 end:0x140 dev:<NULL>
------------[ cut here ]------------
 kernel BUG at net/core/skbuff.c:206 !
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 0 UID: 0 PID: 5880 Comm: syz-executor172 Not tainted 6.13.0-rc3-syzkaller-00762-g9268abe611b0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
 RIP: 0010:skb_panic net/core/skbuff.c:206 [inline]
 RIP: 0010:skb_under_panic+0x14b/0x150 net/core/skbuff.c:216
Code: 0b 8d 48 c7 c6 9e 6c 26 8e 48 8b 54 24 08 8b 0c 24 44 8b 44 24 04 4d 89 e9 50 41 54 41 57 41 56 e8 3a 5a 79 f7 48 83 c4 20 90 <0f> 0b 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3
RSP: 0018:ffffc90003baf5b8 EFLAGS: 00010286
RAX: 0000000000000087 RBX: dffffc0000000000 RCX: 8565c1eec37aa000
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: ffff88802616fb50 R08: ffffffff817f0a4c R09: 1ffff92000775e50
R10: dffffc0000000000 R11: fffff52000775e51 R12: 0000000000000140
R13: ffff88807a1d5800 R14: ffff88807a1d5810 R15: 0000000000000014
FS:  00007fa03261f6c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd65753000 CR3: 0000000031720000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
  skb_push+0xe5/0x100 net/core/skbuff.c:2636
  vlan_get_tci+0x272/0x550 net/packet/af_packet.c:565
  packet_recvmsg+0x13c9/0x1ef0 net/packet/af_packet.c:3616
  sock_recvmsg_nosec net/socket.c:1044 [inline]
  sock_recvmsg+0x22f/0x280 net/socket.c:1066
  ____sys_recvmsg+0x1c6/0x480 net/socket.c:2814
  ___sys_recvmsg net/socket.c:2856 [inline]
  do_recvmmsg+0x426/0xab0 net/socket.c:2951
  __sys_recvmmsg net/socket.c:3025 [inline]
  __do_sys_recvmmsg net/socket.c:3048 [inline]
  __se_sys_recvmmsg net/socket.c:3041 [inline]
  __x64_sys_recvmmsg+0x199/0x250 net/socket.c:3041
  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
  do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83

Fixes: 79eecf6 ("af_packet: Handle outgoing VLAN packets without hardware offloading")
Reported-by: syzbot+8400677f3fd43f37d3bc@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/6772c485.050a0220.2f3838.04c6.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Chengen Du <chengen.du@canonical.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20241230161004.2681892-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
norov pushed a commit that referenced this pull request Jan 14, 2025
Blamed commit forgot MSG_PEEK case, allowing a crash [1] as found
by syzbot.

Rework vlan_get_protocol_dgram() to not touch skb at all,
so that it can be used from many cpus on the same skb.

Add a const qualifier to skb argument.

[1]
skbuff: skb_under_panic: text:ffffffff8a8ccd05 len:29 put:14 head:ffff88807fc8e400 data:ffff88807fc8e3f4 tail:0x11 end:0x140 dev:<NULL>
------------[ cut here ]------------
 kernel BUG at net/core/skbuff.c:206 !
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 1 UID: 0 PID: 5892 Comm: syz-executor883 Not tainted 6.13.0-rc4-syzkaller-00054-gd6ef8b40d075 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
 RIP: 0010:skb_panic net/core/skbuff.c:206 [inline]
 RIP: 0010:skb_under_panic+0x14b/0x150 net/core/skbuff.c:216
Code: 0b 8d 48 c7 c6 86 d5 25 8e 48 8b 54 24 08 8b 0c 24 44 8b 44 24 04 4d 89 e9 50 41 54 41 57 41 56 e8 5a 69 79 f7 48 83 c4 20 90 <0f> 0b 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3
RSP: 0018:ffffc900038d7638 EFLAGS: 00010282
RAX: 0000000000000087 RBX: dffffc0000000000 RCX: 609ffd18ea660600
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: ffff88802483c8d0 R08: ffffffff817f0a8c R09: 1ffff9200071ae60
R10: dffffc0000000000 R11: fffff5200071ae61 R12: 0000000000000140
R13: ffff88807fc8e400 R14: ffff88807fc8e3f4 R15: 0000000000000011
FS:  00007fbac5e006c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbac5e00d58 CR3: 000000001238e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
  skb_push+0xe5/0x100 net/core/skbuff.c:2636
  vlan_get_protocol_dgram+0x165/0x290 net/packet/af_packet.c:585
  packet_recvmsg+0x948/0x1ef0 net/packet/af_packet.c:3552
  sock_recvmsg_nosec net/socket.c:1033 [inline]
  sock_recvmsg+0x22f/0x280 net/socket.c:1055
  ____sys_recvmsg+0x1c6/0x480 net/socket.c:2803
  ___sys_recvmsg net/socket.c:2845 [inline]
  do_recvmmsg+0x426/0xab0 net/socket.c:2940
  __sys_recvmmsg net/socket.c:3014 [inline]
  __do_sys_recvmmsg net/socket.c:3037 [inline]
  __se_sys_recvmmsg net/socket.c:3030 [inline]
  __x64_sys_recvmmsg+0x199/0x250 net/socket.c:3030
  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
  do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Fixes: 79eecf6 ("af_packet: Handle outgoing VLAN packets without hardware offloading")
Reported-by: syzbot+74f70bb1cb968bf09e4f@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/6772c485.050a0220.2f3838.04c5.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Chengen Du <chengen.du@canonical.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20241230161004.2681892-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
norov pushed a commit that referenced this pull request Jan 14, 2025
[BUG]
Syzbot reported a crash with the following call trace:

  BTRFS info (device loop0): scrub: started on devid 1
  BUG: kernel NULL pointer dereference, address: 0000000000000208
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 106e70067 P4D 106e70067 PUD 107143067 PMD 0
  Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI
  CPU: 1 UID: 0 PID: 689 Comm: repro Kdump: loaded Tainted: G           O       6.13.0-rc4-custom+ torvalds#206
  Tainted: [O]=OOT_MODULE
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS unknown 02/02/2022
  RIP: 0010:find_first_extent_item+0x26/0x1f0 [btrfs]
  Call Trace:
   <TASK>
   scrub_find_fill_first_stripe+0x13d/0x3b0 [btrfs]
   scrub_simple_mirror+0x175/0x260 [btrfs]
   scrub_stripe+0x5d4/0x6c0 [btrfs]
   scrub_chunk+0xbb/0x170 [btrfs]
   scrub_enumerate_chunks+0x2f4/0x5f0 [btrfs]
   btrfs_scrub_dev+0x240/0x600 [btrfs]
   btrfs_ioctl+0x1dc8/0x2fa0 [btrfs]
   ? do_sys_openat2+0xa5/0xf0
   __x64_sys_ioctl+0x97/0xc0
   do_syscall_64+0x4f/0x120
   entry_SYSCALL_64_after_hwframe+0x76/0x7e
   </TASK>

[CAUSE]
The reproducer is using a corrupted image where extent tree root is
corrupted, thus forcing to use "rescue=all,ro" mount option to mount the
image.

Then it triggered a scrub, but since scrub relies on extent tree to find
where the data/metadata extents are, scrub_find_fill_first_stripe()
relies on an non-empty extent root.

But unfortunately scrub_find_fill_first_stripe() doesn't really expect
an NULL pointer for extent root, it use extent_root to grab fs_info and
triggered a NULL pointer dereference.

[FIX]
Add an extra check for a valid extent root at the beginning of
scrub_find_fill_first_stripe().

The new error path is introduced by 42437a6 ("btrfs: introduce
mount option rescue=ignorebadroots"), but that's pretty old, and later
commit b979547 ("btrfs: scrub: introduce helper to find and fill
sector info for a scrub_stripe") changed how we do scrub.

So for kernels older than 6.6, the fix will need manual backport.

Reported-by: syzbot+339e9dbe3a2ca419b85d@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/67756935.050a0220.25abdd.0a12.GAE@google.com/
Fixes: 42437a6 ("btrfs: introduce mount option rescue=ignorebadroots")
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
norov pushed a commit that referenced this pull request Jan 14, 2025
Since the input data length passed to zlib_compress_folios() can be
arbitrary, always setting strm.avail_in to a multiple of PAGE_SIZE may
cause read-in bytes to exceed the input range. Currently this triggers
an assert in btrfs_compress_folios() on the debug kernel (see below).
Fix strm.avail_in calculation for S390 hardware acceleration path.

  assertion failed: *total_in <= orig_len, in fs/btrfs/compression.c:1041
  ------------[ cut here ]------------
  kernel BUG at fs/btrfs/compression.c:1041!
  monitor event: 0040 ilc:2 [#1] PREEMPT SMP
  CPU: 16 UID: 0 PID: 325 Comm: kworker/u273:3 Not tainted 6.13.0-20241204.rc1.git6.fae3b21430ca.300.fc41.s390x+debug #1
  Hardware name: IBM 3931 A01 703 (z/VM 7.4.0)
  Workqueue: btrfs-delalloc btrfs_work_helper
  Krnl PSW : 0704d00180000000 0000021761df6538 (btrfs_compress_folios+0x198/0x1a0)
             R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:1 PM:0 RI:0 EA:3
  Krnl GPRS: 0000000080000000 0000000000000001 0000000000000047 0000000000000000
             0000000000000006 ffffff01757bb000 000001976232fcc0 000000000000130c
             000001976232fcd0 000001976232fcc8 00000118ff4a0e30 0000000000000001
             00000111821ab400 0000011100000000 0000021761df6534 000001976232fb58
  Krnl Code: 0000021761df6528: c020006f5ef4        larl    %r2,0000021762be2310
             0000021761df652e: c0e5ffbd09d5        brasl   %r14,00000217615978d8
            #0000021761df6534: af000000            mc      0,0
            >0000021761df6538: 0707                bcr     0,%r7
             0000021761df653a: 0707                bcr     0,%r7
             0000021761df653c: 0707                bcr     0,%r7
             0000021761df653e: 0707                bcr     0,%r7
             0000021761df6540: c004004bb7ec        brcl    0,000002176276d518
  Call Trace:
   [<0000021761df6538>] btrfs_compress_folios+0x198/0x1a0
  ([<0000021761df6534>] btrfs_compress_folios+0x194/0x1a0)
   [<0000021761d97788>] compress_file_range+0x3b8/0x6d0
   [<0000021761dcee7c>] btrfs_work_helper+0x10c/0x160
   [<0000021761645760>] process_one_work+0x2b0/0x5d0
   [<000002176164637e>] worker_thread+0x20e/0x3e0
   [<000002176165221a>] kthread+0x15a/0x170
   [<00000217615b859c>] __ret_from_fork+0x3c/0x60
   [<00000217626e72d2>] ret_from_fork+0xa/0x38
  INFO: lockdep is turned off.
  Last Breaking-Event-Address:
   [<0000021761597924>] _printk+0x4c/0x58
  Kernel panic - not syncing: Fatal exception: panic_on_oops

Fixes: fd1e75d ("btrfs: make compression path to be subpage compatible")
CC: stable@vger.kernel.org # 6.12+
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Signed-off-by: David Sterba <dsterba@suse.com>
norov pushed a commit that referenced this pull request Jan 14, 2025
DC driver is using two different values to define the maximum number of
surfaces: MAX_SURFACES and MAX_SURFACE_NUM. Consolidate MAX_SURFACES as
the unique definition for surface updates across DC.

It fixes page fault faced by Cosmic users on AMD display versions that
support two overlay planes, since the introduction of cursor overlay
mode.

[Nov26 21:33] BUG: unable to handle page fault for address: 0000000051d0f08b
[  +0.000015] #PF: supervisor read access in kernel mode
[  +0.000006] #PF: error_code(0x0000) - not-present page
[  +0.000005] PGD 0 P4D 0
[  +0.000007] Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI
[  +0.000006] CPU: 4 PID: 71 Comm: kworker/u32:6 Not tainted 6.10.0+ torvalds#300
[  +0.000006] Hardware name: Valve Jupiter/Jupiter, BIOS F7A0131 01/30/2024
[  +0.000007] Workqueue: events_unbound commit_work [drm_kms_helper]
[  +0.000040] RIP: 0010:copy_stream_update_to_stream.isra.0+0x30d/0x750 [amdgpu]
[  +0.000847] Code: 8b 10 49 89 94 24 f8 00 00 00 48 8b 50 08 49 89 94 24 00 01 00 00 8b 40 10 41 89 84 24 08 01 00 00 49 8b 45 78 48 85 c0 74 0b <0f> b6 00 41 88 84 24 90 64 00 00 49 8b 45 60 48 85 c0 74 3b 48 8b
[  +0.000010] RSP: 0018:ffffc203802f79a0 EFLAGS: 00010206
[  +0.000009] RAX: 0000000051d0f08b RBX: 0000000000000004 RCX: ffff9f964f0a8070
[  +0.000004] RDX: ffff9f9710f90e40 RSI: ffff9f96600c8000 RDI: ffff9f964f000000
[  +0.000004] RBP: ffffc203802f79f8 R08: 0000000000000000 R09: 0000000000000000
[  +0.000005] R10: 0000000000000000 R11: 0000000000000000 R12: ffff9f96600c8000
[  +0.000004] R13: ffff9f9710f90e40 R14: ffff9f964f000000 R15: ffff9f96600c8000
[  +0.000004] FS:  0000000000000000(0000) GS:ffff9f9970000000(0000) knlGS:0000000000000000
[  +0.000005] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  +0.000005] CR2: 0000000051d0f08b CR3: 00000002e6a20000 CR4: 0000000000350ef0
[  +0.000005] Call Trace:
[  +0.000011]  <TASK>
[  +0.000010]  ? __die_body.cold+0x19/0x27
[  +0.000012]  ? page_fault_oops+0x15a/0x2d0
[  +0.000014]  ? exc_page_fault+0x7e/0x180
[  +0.000009]  ? asm_exc_page_fault+0x26/0x30
[  +0.000013]  ? copy_stream_update_to_stream.isra.0+0x30d/0x750 [amdgpu]
[  +0.000739]  ? dc_commit_state_no_check+0xd6c/0xe70 [amdgpu]
[  +0.000470]  update_planes_and_stream_state+0x49b/0x4f0 [amdgpu]
[  +0.000450]  ? srso_return_thunk+0x5/0x5f
[  +0.000009]  ? commit_minimal_transition_state+0x239/0x3d0 [amdgpu]
[  +0.000446]  update_planes_and_stream_v2+0x24a/0x590 [amdgpu]
[  +0.000464]  ? srso_return_thunk+0x5/0x5f
[  +0.000009]  ? sort+0x31/0x50
[  +0.000007]  ? amdgpu_dm_atomic_commit_tail+0x159f/0x3a30 [amdgpu]
[  +0.000508]  ? srso_return_thunk+0x5/0x5f
[  +0.000009]  ? amdgpu_crtc_get_scanout_position+0x28/0x40 [amdgpu]
[  +0.000377]  ? srso_return_thunk+0x5/0x5f
[  +0.000009]  ? drm_crtc_vblank_helper_get_vblank_timestamp_internal+0x160/0x390 [drm]
[  +0.000058]  ? srso_return_thunk+0x5/0x5f
[  +0.000005]  ? dma_fence_default_wait+0x8c/0x260
[  +0.000010]  ? srso_return_thunk+0x5/0x5f
[  +0.000005]  ? wait_for_completion_timeout+0x13b/0x170
[  +0.000006]  ? srso_return_thunk+0x5/0x5f
[  +0.000005]  ? dma_fence_wait_timeout+0x108/0x140
[  +0.000010]  ? commit_tail+0x94/0x130 [drm_kms_helper]
[  +0.000024]  ? process_one_work+0x177/0x330
[  +0.000008]  ? worker_thread+0x266/0x3a0
[  +0.000006]  ? __pfx_worker_thread+0x10/0x10
[  +0.000004]  ? kthread+0xd2/0x100
[  +0.000006]  ? __pfx_kthread+0x10/0x10
[  +0.000006]  ? ret_from_fork+0x34/0x50
[  +0.000004]  ? __pfx_kthread+0x10/0x10
[  +0.000005]  ? ret_from_fork_asm+0x1a/0x30
[  +0.000011]  </TASK>

Fixes: 1b04dcc ("drm/amd/display: Introduce overlay cursor mode")
Suggested-by: Leo Li <sunpeng.li@amd.com>
Link: https://gitlab.freedesktop.org/drm/amd/-/issues/3693
Signed-off-by: Melissa Wen <mwen@igalia.com>
Reviewed-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 1c86c81)
Cc: stable@vger.kernel.org
norov pushed a commit that referenced this pull request Jan 14, 2025
dm_get_plane_scale doesn't take into account plane scaled size equal to
zero, leading to a kernel oops due to division by zero. Fix by setting
out-scale size as zero when the dst size is zero, similar to what is
done by drm_calc_scale(). This issue started with the introduction of
cursor ovelay mode that uses this function to assess cursor mode changes
via dm_crtc_get_cursor_mode() before checking plane state.

[Dec17 17:14] Oops: divide error: 0000 [#1] PREEMPT SMP NOPTI
[  +0.000018] CPU: 5 PID: 1660 Comm: surface-DP-1 Not tainted 6.10.0+ torvalds#231
[  +0.000007] Hardware name: Valve Jupiter/Jupiter, BIOS F7A0131 01/30/2024
[  +0.000004] RIP: 0010:dm_get_plane_scale+0x3f/0x60 [amdgpu]
[  +0.000553] Code: 44 0f b7 41 3a 44 0f b7 49 3e 83 e0 0f 48 0f a3 c2 73 21 69 41 28 e8 03 00 00 31 d2 41 f7 f1 31 d2 89 06 69 41 2c e8 03 00 00 <41> f7 f0 89 07 e9 d7 d8 7e e9 44 89 c8 45 89 c1 41 89 c0 eb d4 66
[  +0.000005] RSP: 0018:ffffa8df0de6b8a0 EFLAGS: 00010246
[  +0.000006] RAX: 00000000000003e8 RBX: ffff9ac65c1f6e00 RCX: ffff9ac65d055500
[  +0.000003] RDX: 0000000000000000 RSI: ffffa8df0de6b8b0 RDI: ffffa8df0de6b8b4
[  +0.000004] RBP: ffff9ac64e7a5800 R08: 0000000000000000 R09: 0000000000000a00
[  +0.000003] R10: 00000000000000ff R11: 0000000000000054 R12: ffff9ac6d0700010
[  +0.000003] R13: ffff9ac65d054f00 R14: ffff9ac65d055500 R15: ffff9ac64e7a60a0
[  +0.000004] FS:  00007f869ea00640(0000) GS:ffff9ac970080000(0000) knlGS:0000000000000000
[  +0.000004] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  +0.000003] CR2: 000055ca701becd0 CR3: 000000010e7f2000 CR4: 0000000000350ef0
[  +0.000004] Call Trace:
[  +0.000007]  <TASK>
[  +0.000006]  ? __die_body.cold+0x19/0x27
[  +0.000009]  ? die+0x2e/0x50
[  +0.000007]  ? do_trap+0xca/0x110
[  +0.000007]  ? do_error_trap+0x6a/0x90
[  +0.000006]  ? dm_get_plane_scale+0x3f/0x60 [amdgpu]
[  +0.000504]  ? exc_divide_error+0x38/0x50
[  +0.000005]  ? dm_get_plane_scale+0x3f/0x60 [amdgpu]
[  +0.000488]  ? asm_exc_divide_error+0x1a/0x20
[  +0.000011]  ? dm_get_plane_scale+0x3f/0x60 [amdgpu]
[  +0.000593]  dm_crtc_get_cursor_mode+0x33f/0x430 [amdgpu]
[  +0.000562]  amdgpu_dm_atomic_check+0x2ef/0x1770 [amdgpu]
[  +0.000501]  drm_atomic_check_only+0x5e1/0xa30 [drm]
[  +0.000047]  drm_mode_atomic_ioctl+0x832/0xcb0 [drm]
[  +0.000050]  ? __pfx_drm_mode_atomic_ioctl+0x10/0x10 [drm]
[  +0.000047]  drm_ioctl_kernel+0xb3/0x100 [drm]
[  +0.000062]  drm_ioctl+0x27a/0x4f0 [drm]
[  +0.000049]  ? __pfx_drm_mode_atomic_ioctl+0x10/0x10 [drm]
[  +0.000055]  amdgpu_drm_ioctl+0x4e/0x90 [amdgpu]
[  +0.000360]  __x64_sys_ioctl+0x97/0xd0
[  +0.000010]  do_syscall_64+0x82/0x190
[  +0.000008]  ? __pfx_drm_mode_createblob_ioctl+0x10/0x10 [drm]
[  +0.000044]  ? srso_return_thunk+0x5/0x5f
[  +0.000006]  ? drm_ioctl_kernel+0xb3/0x100 [drm]
[  +0.000040]  ? srso_return_thunk+0x5/0x5f
[  +0.000005]  ? __check_object_size+0x50/0x220
[  +0.000007]  ? srso_return_thunk+0x5/0x5f
[  +0.000005]  ? srso_return_thunk+0x5/0x5f
[  +0.000005]  ? drm_ioctl+0x2a4/0x4f0 [drm]
[  +0.000039]  ? __pfx_drm_mode_createblob_ioctl+0x10/0x10 [drm]
[  +0.000043]  ? srso_return_thunk+0x5/0x5f
[  +0.000005]  ? srso_return_thunk+0x5/0x5f
[  +0.000005]  ? __pm_runtime_suspend+0x69/0xc0
[  +0.000006]  ? srso_return_thunk+0x5/0x5f
[  +0.000005]  ? amdgpu_drm_ioctl+0x71/0x90 [amdgpu]
[  +0.000366]  ? srso_return_thunk+0x5/0x5f
[  +0.000006]  ? syscall_exit_to_user_mode+0x77/0x210
[  +0.000007]  ? srso_return_thunk+0x5/0x5f
[  +0.000005]  ? do_syscall_64+0x8e/0x190
[  +0.000006]  ? srso_return_thunk+0x5/0x5f
[  +0.000006]  ? do_syscall_64+0x8e/0x190
[  +0.000006]  ? srso_return_thunk+0x5/0x5f
[  +0.000007]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[  +0.000008] RIP: 0033:0x55bb7cd962bc
[  +0.000007] Code: 4c 89 6c 24 18 4c 89 64 24 20 4c 89 74 24 28 0f 57 c0 0f 11 44 24 30 89 c7 48 8d 54 24 08 b8 10 00 00 00 be bc 64 38 c0 0f 05 <49> 89 c7 48 83 3b 00 74 09 4c 89 c7 ff 15 62 64 99 00 48 83 7b 18
[  +0.000005] RSP: 002b:00007f869e9f4da0 EFLAGS: 00000217 ORIG_RAX: 0000000000000010
[  +0.000007] RAX: ffffffffffffffda RBX: 00007f869e9f4fb8 RCX: 000055bb7cd962bc
[  +0.000004] RDX: 00007f869e9f4da8 RSI: 00000000c03864bc RDI: 000000000000003b
[  +0.000003] RBP: 000055bb9ddcbcc0 R08: 00007f86541b9920 R09: 0000000000000009
[  +0.000004] R10: 0000000000000004 R11: 0000000000000217 R12: 00007f865406c6b0
[  +0.000003] R13: 00007f86541b5290 R14: 00007f865410b700 R15: 000055bb9ddcbc18
[  +0.000009]  </TASK>

Fixes: 1b04dcc ("drm/amd/display: Introduce overlay cursor mode")
Link: https://gitlab.freedesktop.org/drm/amd/-/issues/3729
Reported-by: Fabio Scaccabarozzi <fsvm88@gmail.com>
Co-developed-by: Fabio Scaccabarozzi <fsvm88@gmail.com>
Signed-off-by: Fabio Scaccabarozzi <fsvm88@gmail.com>
Signed-off-by: Melissa Wen <mwen@igalia.com>
Reviewed-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit ab75a0d)
Cc: stable@vger.kernel.org
norov pushed a commit that referenced this pull request Jan 14, 2025
die() can be called in exception handler, and therefore cannot sleep.
However, die() takes spinlock_t which can sleep with PREEMPT_RT enabled.
That causes the following warning:

BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48
in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 285, name: mutex
preempt_count: 110001, expected: 0
RCU nest depth: 0, expected: 0
CPU: 0 UID: 0 PID: 285 Comm: mutex Not tainted 6.12.0-rc7-00022-ge19049cf7d56-dirty torvalds#234
Hardware name: riscv-virtio,qemu (DT)
Call Trace:
    dump_backtrace+0x1c/0x24
    show_stack+0x2c/0x38
    dump_stack_lvl+0x5a/0x72
    dump_stack+0x14/0x1c
    __might_resched+0x130/0x13a
    rt_spin_lock+0x2a/0x5c
    die+0x24/0x112
    do_trap_insn_illegal+0xa0/0xea
    _new_vmalloc_restore_context_a0+0xcc/0xd8
Oops - illegal instruction [#1]

Switch to use raw_spinlock_t, which does not sleep even with PREEMPT_RT
enabled.

Fixes: 76d2a04 ("RISC-V: Init and Halt Code")
Signed-off-by: Nam Cao <namcao@linutronix.de>
Cc: stable@vger.kernel.org
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://lore.kernel.org/r/20241118091333.1185288-1-namcao@linutronix.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
norov pushed a commit that referenced this pull request Jan 14, 2025
If GuC fails to load, the driver wedges, but in the process it tries to
do stuff that may not be initialized yet. This moves the
xe_gt_tlb_invalidation_init() to be done earlier: as its own doc says,
it's a software-only initialization and should had been named with the
_early() suffix.

Move it to be called by xe_gt_init_early(), so the locks and seqno are
initialized, avoiding a NULL ptr deref when wedging:

	xe 0000:03:00.0: [drm] *ERROR* GT0: load failed: status: Reset = 0, BootROM = 0x50, UKernel = 0x00, MIA = 0x00, Auth = 0x01
	xe 0000:03:00.0: [drm] *ERROR* GT0: firmware signature verification failed
	xe 0000:03:00.0: [drm] *ERROR* CRITICAL: Xe has declared device 0000:03:00.0 as wedged.
	...
	BUG: kernel NULL pointer dereference, address: 0000000000000000
	#PF: supervisor read access in kernel mode
	#PF: error_code(0x0000) - not-present page
	PGD 0 P4D 0
	Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI
	CPU: 9 UID: 0 PID: 3908 Comm: modprobe Tainted: G     U  W          6.13.0-rc4-xe+ #3
	Tainted: [U]=USER, [W]=WARN
	Hardware name: Intel Corporation Alder Lake Client Platform/AlderLake-S ADP-S DDR5 UDIMM CRB, BIOS ADLSFWI1.R00.3275.A00.2207010640 07/01/2022
	RIP: 0010:xe_gt_tlb_invalidation_reset+0x75/0x110 [xe]

This can be easily triggered by poking the GuC binary to force a
signature failure. There will still be an extra message,

	xe 0000:03:00.0: [drm] *ERROR* GT0: GuC mmio request 0x4100: no reply 0x4100

but that's better than a NULL ptr deref.

Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/3956
Fixes: c9474b7 ("drm/xe: Wedge the entire device")
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250103001111.331684-2-lucas.demarchi@intel.com
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
(cherry picked from commit 5001ef3)
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
norov pushed a commit that referenced this pull request Jan 14, 2025
We found a timeout problem with the pldm command on our system.  The
reason is that the MCTP-I3C driver has a race condition when receiving
multiple-packet messages in multi-thread, resulting in a wrong packet
order problem.

We identified this problem by adding a debug message to the
mctp_i3c_read function.

According to the MCTP spec, a multiple-packet message must be composed
in sequence, and if there is a wrong sequence, the whole message will be
discarded and wait for the next SOM.
For example, SOM → Pkt Seq #2 → Pkt Seq #1 → Pkt Seq #3 → EOM.

Therefore, we try to solve this problem by adding a mutex to the
mctp_i3c_read function.  Before the modification, when a command
requesting a multiple-packet message response is sent consecutively, an
error usually occurs within 100 loops.  After the mutex, it can go
through 40000 loops without any error, and it seems to run well.

Fixes: c8755b2 ("mctp i3c: MCTP I3C driver")
Signed-off-by: Leo Yang <Leo-Yang@quantatw.com>
Link: https://patch.msgid.link/20250107031529.3296094-1-Leo-Yang@quantatw.com
[pabeni@redhat.com: dropped already answered question from changelog]
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
norov pushed a commit that referenced this pull request Jan 14, 2025
When cmd_alloc_index(), fails cmd_work_handler() needs
to complete ent->slotted before returning early.
Otherwise the task which issued the command may hang:

   mlx5_core 0000:01:00.0: cmd_work_handler:877:(pid 3880418): failed to allocate command entry
   INFO: task kworker/13:2:4055883 blocked for more than 120 seconds.
         Not tainted 4.19.90-25.44.v2101.ky10.aarch64 #1
   "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
   kworker/13:2    D    0 4055883      2 0x00000228
   Workqueue: events mlx5e_tx_dim_work [mlx5_core]
   Call trace:
      __switch_to+0xe8/0x150
      __schedule+0x2a8/0x9b8
      schedule+0x2c/0x88
      schedule_timeout+0x204/0x478
      wait_for_common+0x154/0x250
      wait_for_completion+0x28/0x38
      cmd_exec+0x7a0/0xa00 [mlx5_core]
      mlx5_cmd_exec+0x54/0x80 [mlx5_core]
      mlx5_core_modify_cq+0x6c/0x80 [mlx5_core]
      mlx5_core_modify_cq_moderation+0xa0/0xb8 [mlx5_core]
      mlx5e_tx_dim_work+0x54/0x68 [mlx5_core]
      process_one_work+0x1b0/0x448
      worker_thread+0x54/0x468
      kthread+0x134/0x138
      ret_from_fork+0x10/0x18

Fixes: 485d65e ("net/mlx5: Add a timeout to acquire the command queue semaphore")
Signed-off-by: Chenguang Zhao <zhaochenguang@kylinos.cn>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Acked-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://patch.msgid.link/20250108030009.68520-1-zhaochenguang@kylinos.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
norov pushed a commit that referenced this pull request Jan 14, 2025
Using the 'net' structure via 'current' is not recommended for different
reasons.

First, if the goal is to use it to read or write per-netns data, this is
inconsistent with how the "generic" sysctl entries are doing: directly
by only using pointers set to the table entry, e.g. table->data. Linked
to that, the per-netns data should always be obtained from the table
linked to the netns it had been created for, which may not coincide with
the reader's or writer's netns.

Another reason is that access to current->nsproxy->netns can oops if
attempted when current->nsproxy had been dropped when the current task
is exiting. This is what syzbot found, when using acct(2):

  Oops: general protection fault, probably for non-canonical address 0xdffffc0000000005: 0000 [#1] PREEMPT SMP KASAN PTI
  KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f]
  CPU: 1 UID: 0 PID: 5924 Comm: syz-executor Not tainted 6.13.0-rc5-syzkaller-00004-gccb98ccef0e5 #0
  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
  RIP: 0010:proc_scheduler+0xc6/0x3c0 net/mptcp/ctrl.c:125
  Code: 03 42 80 3c 38 00 0f 85 fe 02 00 00 4d 8b a4 24 08 09 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d 7c 24 28 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 cc 02 00 00 4d 8b 7c 24 28 48 8d 84 24 c8 00 00
  RSP: 0018:ffffc900034774e8 EFLAGS: 00010206

  RAX: dffffc0000000000 RBX: 1ffff9200068ee9e RCX: ffffc90003477620
  RDX: 0000000000000005 RSI: ffffffff8b08f91e RDI: 0000000000000028
  RBP: 0000000000000001 R08: ffffc90003477710 R09: 0000000000000040
  R10: 0000000000000040 R11: 00000000726f7475 R12: 0000000000000000
  R13: ffffc90003477620 R14: ffffc90003477710 R15: dffffc0000000000
  FS:  0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007fee3cd452d8 CR3: 000000007d116000 CR4: 00000000003526f0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   <TASK>
   proc_sys_call_handler+0x403/0x5d0 fs/proc/proc_sysctl.c:601
   __kernel_write_iter+0x318/0xa80 fs/read_write.c:612
   __kernel_write+0xf6/0x140 fs/read_write.c:632
   do_acct_process+0xcb0/0x14a0 kernel/acct.c:539
   acct_pin_kill+0x2d/0x100 kernel/acct.c:192
   pin_kill+0x194/0x7c0 fs/fs_pin.c:44
   mnt_pin_kill+0x61/0x1e0 fs/fs_pin.c:81
   cleanup_mnt+0x3ac/0x450 fs/namespace.c:1366
   task_work_run+0x14e/0x250 kernel/task_work.c:239
   exit_task_work include/linux/task_work.h:43 [inline]
   do_exit+0xad8/0x2d70 kernel/exit.c:938
   do_group_exit+0xd3/0x2a0 kernel/exit.c:1087
   get_signal+0x2576/0x2610 kernel/signal.c:3017
   arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337
   exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
   exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
   __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
   syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218
   do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
   entry_SYSCALL_64_after_hwframe+0x77/0x7f
  RIP: 0033:0x7fee3cb87a6a
  Code: Unable to access opcode bytes at 0x7fee3cb87a40.
  RSP: 002b:00007fffcccac688 EFLAGS: 00000202 ORIG_RAX: 0000000000000037
  RAX: 0000000000000000 RBX: 00007fffcccac710 RCX: 00007fee3cb87a6a
  RDX: 0000000000000041 RSI: 0000000000000000 RDI: 0000000000000003
  RBP: 0000000000000003 R08: 00007fffcccac6ac R09: 00007fffcccacac7
  R10: 00007fffcccac710 R11: 0000000000000202 R12: 00007fee3cd49500
  R13: 00007fffcccac6ac R14: 0000000000000000 R15: 00007fee3cd4b000
   </TASK>
  Modules linked in:
  ---[ end trace 0000000000000000 ]---
  RIP: 0010:proc_scheduler+0xc6/0x3c0 net/mptcp/ctrl.c:125
  Code: 03 42 80 3c 38 00 0f 85 fe 02 00 00 4d 8b a4 24 08 09 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d 7c 24 28 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 cc 02 00 00 4d 8b 7c 24 28 48 8d 84 24 c8 00 00
  RSP: 0018:ffffc900034774e8 EFLAGS: 00010206
  RAX: dffffc0000000000 RBX: 1ffff9200068ee9e RCX: ffffc90003477620
  RDX: 0000000000000005 RSI: ffffffff8b08f91e RDI: 0000000000000028
  RBP: 0000000000000001 R08: ffffc90003477710 R09: 0000000000000040
  R10: 0000000000000040 R11: 00000000726f7475 R12: 0000000000000000
  R13: ffffc90003477620 R14: ffffc90003477710 R15: dffffc0000000000
  FS:  0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007fee3cd452d8 CR3: 000000007d116000 CR4: 00000000003526f0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  ----------------
  Code disassembly (best guess), 1 bytes skipped:
     0:	42 80 3c 38 00       	cmpb   $0x0,(%rax,%r15,1)
     5:	0f 85 fe 02 00 00    	jne    0x309
     b:	4d 8b a4 24 08 09 00 	mov    0x908(%r12),%r12
    12:	00
    13:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
    1a:	fc ff df
    1d:	49 8d 7c 24 28       	lea    0x28(%r12),%rdi
    22:	48 89 fa             	mov    %rdi,%rdx
    25:	48 c1 ea 03          	shr    $0x3,%rdx
  * 29:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1) <-- trapping instruction
    2d:	0f 85 cc 02 00 00    	jne    0x2ff
    33:	4d 8b 7c 24 28       	mov    0x28(%r12),%r15
    38:	48                   	rex.W
    39:	8d                   	.byte 0x8d
    3a:	84 24 c8             	test   %ah,(%rax,%rcx,8)

Here with 'net.mptcp.scheduler', the 'net' structure is not really
needed, because the table->data already has a pointer to the current
scheduler, the only thing needed from the per-netns data.
Simply use 'data', instead of getting (most of the time) the same thing,
but from a longer and indirect way.

Fixes: 6963c50 ("mptcp: only allow set existing scheduler for net.mptcp.scheduler")
Cc: stable@vger.kernel.org
Reported-by: syzbot+e364f774c6f57f2c86d1@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/67769ecb.050a0220.3a8527.003f.GAE@google.com
Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20250108-net-sysctl-current-nsproxy-v1-2-5df34b2083e8@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
norov pushed a commit that referenced this pull request Jan 14, 2025
Max Makarov reported kernel panic [1] in perf user callchain code.

The reason for that is the race between uprobe_free_utask and bpf
profiler code doing the perf user stack unwind and is triggered
within uprobe_free_utask function:
  - after current->utask is freed and
  - before current->utask is set to NULL

 general protection fault, probably for non-canonical address 0x9e759c37ee555c76: 0000 [#1] SMP PTI
 RIP: 0010:is_uprobe_at_func_entry+0x28/0x80
 ...
  ? die_addr+0x36/0x90
  ? exc_general_protection+0x217/0x420
  ? asm_exc_general_protection+0x26/0x30
  ? is_uprobe_at_func_entry+0x28/0x80
  perf_callchain_user+0x20a/0x360
  get_perf_callchain+0x147/0x1d0
  bpf_get_stackid+0x60/0x90
  bpf_prog_9aac297fb833e2f5_do_perf_event+0x434/0x53b
  ? __smp_call_single_queue+0xad/0x120
  bpf_overflow_handler+0x75/0x110
  ...
  asm_sysvec_apic_timer_interrupt+0x1a/0x20
 RIP: 0010:__kmem_cache_free+0x1cb/0x350
 ...
  ? uprobe_free_utask+0x62/0x80
  ? acct_collect+0x4c/0x220
  uprobe_free_utask+0x62/0x80
  mm_release+0x12/0xb0
  do_exit+0x26b/0xaa0
  __x64_sys_exit+0x1b/0x20
  do_syscall_64+0x5a/0x80

It can be easily reproduced by running following commands in
separate terminals:

  # while :; do bpftrace -e 'uprobe:/bin/ls:_start  { printf("hit\n"); }' -c ls; done
  # bpftrace -e 'profile:hz:100000 { @[ustack()] = count(); }'

Fixing this by making sure current->utask pointer is set to NULL
before we start to release the utask object.

[1] grafana/pyroscope#3673

Fixes: cfa7f3d ("perf,x86: avoid missing caller address in stack traces captured in uprobe")
Reported-by: Max Makarov <maxpain@linux.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20250109141440.2692173-1-jolsa@kernel.org
norov pushed a commit that referenced this pull request Jan 14, 2025
This reverts commit eaebeb9.

Commit eaebeb9 ("mm: zswap: fix race between [de]compression and CPU
hotunplug") used the CPU hotplug lock in zswap compress/decompress
operations to protect against a race with CPU hotunplug making some
per-CPU resources go away.

However, zswap compress/decompress can be reached through reclaim while
the lock is held, resulting in a potential deadlock as reported by syzbot:
======================================================
WARNING: possible circular locking dependency detected
6.13.0-rc6-syzkaller-00006-g5428dc1906dd #0 Not tainted
------------------------------------------------------
kswapd0/89 is trying to acquire lock:
 ffffffff8e7d2ed0 (cpu_hotplug_lock){++++}-{0:0}, at: acomp_ctx_get_cpu mm/zswap.c:886 [inline]
 ffffffff8e7d2ed0 (cpu_hotplug_lock){++++}-{0:0}, at: zswap_compress mm/zswap.c:908 [inline]
 ffffffff8e7d2ed0 (cpu_hotplug_lock){++++}-{0:0}, at: zswap_store_page mm/zswap.c:1439 [inline]
 ffffffff8e7d2ed0 (cpu_hotplug_lock){++++}-{0:0}, at: zswap_store+0xa74/0x1ba0 mm/zswap.c:1546

but task is already holding lock:
 ffffffff8ea355a0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat mm/vmscan.c:6871 [inline]
 ffffffff8ea355a0 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0xb58/0x2f30 mm/vmscan.c:7253

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (fs_reclaim){+.+.}-{0:0}:
        lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
        __fs_reclaim_acquire mm/page_alloc.c:3853 [inline]
        fs_reclaim_acquire+0x88/0x130 mm/page_alloc.c:3867
        might_alloc include/linux/sched/mm.h:318 [inline]
        slab_pre_alloc_hook mm/slub.c:4070 [inline]
        slab_alloc_node mm/slub.c:4148 [inline]
        __kmalloc_cache_node_noprof+0x40/0x3a0 mm/slub.c:4337
        kmalloc_node_noprof include/linux/slab.h:924 [inline]
        alloc_worker kernel/workqueue.c:2638 [inline]
        create_worker+0x11b/0x720 kernel/workqueue.c:2781
        workqueue_prepare_cpu+0xe3/0x170 kernel/workqueue.c:6628
        cpuhp_invoke_callback+0x48d/0x830 kernel/cpu.c:194
        __cpuhp_invoke_callback_range kernel/cpu.c:965 [inline]
        cpuhp_invoke_callback_range kernel/cpu.c:989 [inline]
        cpuhp_up_callbacks kernel/cpu.c:1020 [inline]
        _cpu_up+0x2b3/0x580 kernel/cpu.c:1690
        cpu_up+0x184/0x230 kernel/cpu.c:1722
        cpuhp_bringup_mask+0xdf/0x260 kernel/cpu.c:1788
        cpuhp_bringup_cpus_parallel+0xf9/0x160 kernel/cpu.c:1878
        bringup_nonboot_cpus+0x2b/0x50 kernel/cpu.c:1892
        smp_init+0x34/0x150 kernel/smp.c:1009
        kernel_init_freeable+0x417/0x5d0 init/main.c:1569
        kernel_init+0x1d/0x2b0 init/main.c:1466
        ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
        ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

-> #0 (cpu_hotplug_lock){++++}-{0:0}:
        check_prev_add kernel/locking/lockdep.c:3161 [inline]
        check_prevs_add kernel/locking/lockdep.c:3280 [inline]
        validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904
        __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226
        lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
        percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
        cpus_read_lock+0x42/0x150 kernel/cpu.c:490
        acomp_ctx_get_cpu mm/zswap.c:886 [inline]
        zswap_compress mm/zswap.c:908 [inline]
        zswap_store_page mm/zswap.c:1439 [inline]
        zswap_store+0xa74/0x1ba0 mm/zswap.c:1546
        swap_writepage+0x647/0xce0 mm/page_io.c:279
        shmem_writepage+0x1248/0x1610 mm/shmem.c:1579
        pageout mm/vmscan.c:696 [inline]
        shrink_folio_list+0x35ee/0x57e0 mm/vmscan.c:1374
        shrink_inactive_list mm/vmscan.c:1967 [inline]
        shrink_list mm/vmscan.c:2205 [inline]
        shrink_lruvec+0x16db/0x2f30 mm/vmscan.c:5734
        mem_cgroup_shrink_node+0x385/0x8e0 mm/vmscan.c:6575
        mem_cgroup_soft_reclaim mm/memcontrol-v1.c:312 [inline]
        memcg1_soft_limit_reclaim+0x346/0x810 mm/memcontrol-v1.c:362
        balance_pgdat mm/vmscan.c:6975 [inline]
        kswapd+0x17b3/0x2f30 mm/vmscan.c:7253
        kthread+0x2f0/0x390 kernel/kthread.c:389
        ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
        ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(fs_reclaim);
                               lock(cpu_hotplug_lock);
                               lock(fs_reclaim);
  rlock(cpu_hotplug_lock);

 *** DEADLOCK ***

1 lock held by kswapd0/89:
  #0: ffffffff8ea355a0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat mm/vmscan.c:6871 [inline]
  #0: ffffffff8ea355a0 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0xb58/0x2f30 mm/vmscan.c:7253

stack backtrace:
CPU: 0 UID: 0 PID: 89 Comm: kswapd0 Not tainted 6.13.0-rc6-syzkaller-00006-g5428dc1906dd #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
  __dump_stack lib/dump_stack.c:94 [inline]
  dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
  print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074
  check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2206
  check_prev_add kernel/locking/lockdep.c:3161 [inline]
  check_prevs_add kernel/locking/lockdep.c:3280 [inline]
  validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904
  __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226
  lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
  percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
  cpus_read_lock+0x42/0x150 kernel/cpu.c:490
  acomp_ctx_get_cpu mm/zswap.c:886 [inline]
  zswap_compress mm/zswap.c:908 [inline]
  zswap_store_page mm/zswap.c:1439 [inline]
  zswap_store+0xa74/0x1ba0 mm/zswap.c:1546
  swap_writepage+0x647/0xce0 mm/page_io.c:279
  shmem_writepage+0x1248/0x1610 mm/shmem.c:1579
  pageout mm/vmscan.c:696 [inline]
  shrink_folio_list+0x35ee/0x57e0 mm/vmscan.c:1374
  shrink_inactive_list mm/vmscan.c:1967 [inline]
  shrink_list mm/vmscan.c:2205 [inline]
  shrink_lruvec+0x16db/0x2f30 mm/vmscan.c:5734
  mem_cgroup_shrink_node+0x385/0x8e0 mm/vmscan.c:6575
  mem_cgroup_soft_reclaim mm/memcontrol-v1.c:312 [inline]
  memcg1_soft_limit_reclaim+0x346/0x810 mm/memcontrol-v1.c:362
  balance_pgdat mm/vmscan.c:6975 [inline]
  kswapd+0x17b3/0x2f30 mm/vmscan.c:7253
  kthread+0x2f0/0x390 kernel/kthread.c:389
  ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Revert the change. A different fix for the race with CPU hotunplug will
follow.

Link: https://lkml.kernel.org/r/20250107222236.2715883-1-yosryahmed@google.com
Signed-off-by: Yosry Ahmed <yosryahmed@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kanchana P Sridhar <kanchana.p.sridhar@intel.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Sam Sun <samsun1006219@gmail.com>
Cc: Vitaly Wool <vitalywool@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
norov pushed a commit that referenced this pull request Jan 14, 2025
A livepatch module can contain a special relocation section
.klp.rela.<objname>.<secname> to apply its relocations at the appropriate
time and to additionally access local and unexported symbols.  When
<objname> points to another module, such relocations are processed
separately from the regular module relocation process.  For instance, only
when the target <objname> actually becomes loaded.

With CONFIG_STRICT_MODULE_RWX, when the livepatch core decides to apply
these relocations, their processing results in the following bug:

[   25.827238] BUG: unable to handle page fault for address: 00000000000012ba
[   25.827819] #PF: supervisor read access in kernel mode
[   25.828153] #PF: error_code(0x0000) - not-present page
[   25.828588] PGD 0 P4D 0
[   25.829063] Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI
[   25.829742] CPU: 2 UID: 0 PID: 452 Comm: insmod Tainted: G O  K    6.13.0-rc4-00078-g059dd502b263 #7820
[   25.830417] Tainted: [O]=OOT_MODULE, [K]=LIVEPATCH
[   25.830768] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-20220807_005459-localhost 04/01/2014
[   25.831651] RIP: 0010:memcmp+0x24/0x60
[   25.832190] Code: [...]
[   25.833378] RSP: 0018:ffffa40b403a3ae8 EFLAGS: 00000246
[   25.833637] RAX: 0000000000000000 RBX: ffff93bc81d8e700 RCX: ffffffffc0202000
[   25.834072] RDX: 0000000000000000 RSI: 0000000000000004 RDI: 00000000000012ba
[   25.834548] RBP: ffffa40b403a3b68 R08: ffffa40b403a3b30 R09: 0000004a00000002
[   25.835088] R10: ffffffffffffd222 R11: f000000000000000 R12: 0000000000000000
[   25.835666] R13: ffffffffc02032ba R14: ffffffffc007d1e0 R15: 0000000000000004
[   25.836139] FS:  00007fecef8c3080(0000) GS:ffff93bc8f900000(0000) knlGS:0000000000000000
[   25.836519] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   25.836977] CR2: 00000000000012ba CR3: 0000000002f24000 CR4: 00000000000006f0
[   25.837442] Call Trace:
[   25.838297]  <TASK>
[   25.841083]  __write_relocate_add.constprop.0+0xc7/0x2b0
[   25.841701]  apply_relocate_add+0x75/0xa0
[   25.841973]  klp_write_section_relocs+0x10e/0x140
[   25.842304]  klp_write_object_relocs+0x70/0xa0
[   25.842682]  klp_init_object_loaded+0x21/0xf0
[   25.842972]  klp_enable_patch+0x43d/0x900
[   25.843572]  do_one_initcall+0x4c/0x220
[   25.844186]  do_init_module+0x6a/0x260
[   25.844423]  init_module_from_file+0x9c/0xe0
[   25.844702]  idempotent_init_module+0x172/0x270
[   25.845008]  __x64_sys_finit_module+0x69/0xc0
[   25.845253]  do_syscall_64+0x9e/0x1a0
[   25.845498]  entry_SYSCALL_64_after_hwframe+0x77/0x7f
[   25.846056] RIP: 0033:0x7fecef9eb25d
[   25.846444] Code: [...]
[   25.847563] RSP: 002b:00007ffd0c5d6de8 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
[   25.848082] RAX: ffffffffffffffda RBX: 000055b03f05e470 RCX: 00007fecef9eb25d
[   25.848456] RDX: 0000000000000000 RSI: 000055b001e74e52 RDI: 0000000000000003
[   25.848969] RBP: 00007ffd0c5d6ea0 R08: 0000000000000040 R09: 0000000000004100
[   25.849411] R10: 00007fecefac7b20 R11: 0000000000000246 R12: 000055b001e74e52
[   25.849905] R13: 0000000000000000 R14: 000055b03f05e440 R15: 0000000000000000
[   25.850336]  </TASK>
[   25.850553] Modules linked in: deku(OK+) uinput
[   25.851408] CR2: 00000000000012ba
[   25.852085] ---[ end trace 0000000000000000 ]---

The problem is that the .klp.rela.<objname>.<secname> relocations are
processed after the module was already formed and mod->rw_copy was reset. 
However, the code in __write_relocate_add() calls
module_writable_address() which translates the target address 'loc' still
to 'loc + (mem->rw_copy - mem->base)', with mem->rw_copy now being 0.

Fix the problem by returning directly 'loc' in module_writable_address()
when the module is already formed.  Function __write_relocate_add() knows
to use text_poke() in such a case.

Link: https://lkml.kernel.org/r/20250107153507.14733-1-petr.pavlu@suse.com
Fixes: 0c133b1 ("module: prepare to handle ROX allocations for text")
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
Reported-by: Marek Maslanka <mmaslanka@google.com>
Closes: https://lore.kernel.org/linux-modules/CAGcaFA2hdThQV6mjD_1_U+GNHThv84+MQvMWLgEuX+LVbAyDxg@mail.gmail.com/
Reviewed-by: Petr Mladek <pmladek@suse.com>
Tested-by: Petr Mladek <pmladek@suse.com>
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Petr Mladek <pmladek@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
norov pushed a commit that referenced this pull request Jan 28, 2025
Petr Machata says:

====================
mlxsw: Move Tx header handling to PCI driver

Amit Cohen writes:

Tx header should be added to all packets transmitted from the CPU to
Spectrum ASICs. Historically, handling this header was added as a driver
function, as Tx header is different between Spectrum and Switch-X.

From May 2021, there is no support for SwitchX-2 ASIC, and all the relevant
code was removed.

For now, there is no justification to handle Tx header as part of
spectrum.c, we can handle this as part of PCI, in skb_transmit().

This change will also be useful when XDP support will be added to mlxsw,
as for XDP_TX and XDP_REDIRECT actions, Tx header should be added before
transmitting the packet.

Patch set overview:
Patches #1-#2 add structure to store Tx header info and initialize it
Patch #3 moves definitions of Tx header fields to txheader.h
Patch #4 moves Tx header handling to PCI driver
Patch #5 removes unnecessary attribute
====================

Link: https://patch.msgid.link/cover.1737044384.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
norov pushed a commit that referenced this pull request Jan 28, 2025
It isn't guaranteed that NETWORK_INTERFACE_INFO::LinkSpeed will always
be set by the server, so the client must handle any values and then
prevent oopses like below from happening:

Oops: divide error: 0000 [#1] PREEMPT SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 1323 Comm: cat Not tainted 6.13.0-rc7 #2
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-3.fc41
04/01/2014
RIP: 0010:cifs_debug_data_proc_show+0xa45/0x1460 [cifs] Code: 00 00 48
89 df e8 3b cd 1b c1 41 f6 44 24 2c 04 0f 84 50 01 00 00 48 89 ef e8
e7 d0 1b c1 49 8b 44 24 18 31 d2 49 8d 7c 24 28 <48> f7 74 24 18 48 89
c3 e8 6e cf 1b c1 41 8b 6c 24 28 49 8d 7c 24
RSP: 0018:ffffc90001817be0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff88811230022c RCX: ffffffffc041bd99
RDX: 0000000000000000 RSI: 0000000000000567 RDI: ffff888112300228
RBP: ffff888112300218 R08: fffff52000302f5f R09: ffffed1022fa58ac
R10: ffff888117d2c566 R11: 00000000fffffffe R12: ffff888112300200
R13: 000000012a15343f R14: 0000000000000001 R15: ffff888113f2db58
FS: 00007fe27119e740(0000) GS:ffff888148600000(0000)
knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe2633c5000 CR3: 0000000124da0000 CR4: 0000000000750ef0
PKRU: 55555554
Call Trace:
 <TASK>
 ? __die_body.cold+0x19/0x27
 ? die+0x2e/0x50
 ? do_trap+0x159/0x1b0
 ? cifs_debug_data_proc_show+0xa45/0x1460 [cifs]
 ? do_error_trap+0x90/0x130
 ? cifs_debug_data_proc_show+0xa45/0x1460 [cifs]
 ? exc_divide_error+0x39/0x50
 ? cifs_debug_data_proc_show+0xa45/0x1460 [cifs]
 ? asm_exc_divide_error+0x1a/0x20
 ? cifs_debug_data_proc_show+0xa39/0x1460 [cifs]
 ? cifs_debug_data_proc_show+0xa45/0x1460 [cifs]
 ? seq_read_iter+0x42e/0x790
 seq_read_iter+0x19a/0x790
 proc_reg_read_iter+0xbe/0x110
 ? __pfx_proc_reg_read_iter+0x10/0x10
 vfs_read+0x469/0x570
 ? do_user_addr_fault+0x398/0x760
 ? __pfx_vfs_read+0x10/0x10
 ? find_held_lock+0x8a/0xa0
 ? __pfx_lock_release+0x10/0x10
 ksys_read+0xd3/0x170
 ? __pfx_ksys_read+0x10/0x10
 ? __rcu_read_unlock+0x50/0x270
 ? mark_held_locks+0x1a/0x90
 do_syscall_64+0xbb/0x1d0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe271288911
Code: 00 48 8b 15 01 25 10 00 f7 d8 64 89 02 b8 ff ff ff ff eb bd e8
20 ad 01 00 f3 0f 1e fa 80 3d b5 a7 10 00 00 74 13 31 c0 0f 05 <48> 3d
00 f0 ff ff 77 4f c3 66 0f 1f 44 00 00 55 48 89 e5 48 83 ec
RSP: 002b:00007ffe87c079d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000000000040000 RCX: 00007fe271288911
RDX: 0000000000040000 RSI: 00007fe2633c6000 RDI: 0000000000000003
RBP: 00007ffe87c07a00 R08: 0000000000000000 R09: 00007fe2713e6380
R10: 0000000000000022 R11: 0000000000000246 R12: 0000000000040000
R13: 00007fe2633c6000 R14: 0000000000000003 R15: 0000000000000000
 </TASK>

Fix this by setting cifs_server_iface::speed to a sane value (1Gbps)
by default when link speed is unset.

Cc: Shyam Prasad N <nspmangalore@gmail.com>
Cc: Tom Talpey <tom@talpey.com>
Fixes: a6d8fb5 ("cifs: distribute channels across interfaces based on speed")
Reported-by: Frank Sorenson <sorenson@redhat.com>
Reported-by: Jay Shin <jaeshin@redhat.com>
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
norov pushed a commit that referenced this pull request Jan 28, 2025
During the update procedure, when overwrite element in a pre-allocated
htab, the freeing of old_element is protected by the bucket lock. The
reason why the bucket lock is necessary is that the old_element has
already been stashed in htab->extra_elems after alloc_htab_elem()
returns. If freeing the old_element after the bucket lock is unlocked,
the stashed element may be reused by concurrent update procedure and the
freeing of old_element will run concurrently with the reuse of the
old_element. However, the invocation of check_and_free_fields() may
acquire a spin-lock which violates the lockdep rule because its caller
has already held a raw-spin-lock (bucket lock). The following warning
will be reported when such race happens:

  BUG: scheduling while atomic: test_progs/676/0x00000003
  3 locks held by test_progs/676:
  #0: ffffffff864b0240 (rcu_read_lock_trace){....}-{0:0}, at: bpf_prog_test_run_syscall+0x2c0/0x830
  #1: ffff88810e961188 (&htab->lockdep_key){....}-{2:2}, at: htab_map_update_elem+0x306/0x1500
  #2: ffff8881f4eac1b8 (&base->softirq_expiry_lock){....}-{2:2}, at: hrtimer_cancel_wait_running+0xe9/0x1b0
  Modules linked in: bpf_testmod(O)
  Preemption disabled at:
  [<ffffffff817837a3>] htab_map_update_elem+0x293/0x1500
  CPU: 0 UID: 0 PID: 676 Comm: test_progs Tainted: G ... 6.12.0+ torvalds#11
  Tainted: [W]=WARN, [O]=OOT_MODULE
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)...
  Call Trace:
  <TASK>
  dump_stack_lvl+0x57/0x70
  dump_stack+0x10/0x20
  __schedule_bug+0x120/0x170
  __schedule+0x300c/0x4800
  schedule_rtlock+0x37/0x60
  rtlock_slowlock_locked+0x6d9/0x54c0
  rt_spin_lock+0x168/0x230
  hrtimer_cancel_wait_running+0xe9/0x1b0
  hrtimer_cancel+0x24/0x30
  bpf_timer_delete_work+0x1d/0x40
  bpf_timer_cancel_and_free+0x5e/0x80
  bpf_obj_free_fields+0x262/0x4a0
  check_and_free_fields+0x1d0/0x280
  htab_map_update_elem+0x7fc/0x1500
  bpf_prog_9f90bc20768e0cb9_overwrite_cb+0x3f/0x43
  bpf_prog_ea601c4649694dbd_overwrite_timer+0x5d/0x7e
  bpf_prog_test_run_syscall+0x322/0x830
  __sys_bpf+0x135d/0x3ca0
  __x64_sys_bpf+0x75/0xb0
  x64_sys_call+0x1b5/0xa10
  do_syscall_64+0x3b/0xc0
  entry_SYSCALL_64_after_hwframe+0x4b/0x53
  ...
  </TASK>

It seems feasible to break the reuse and refill of per-cpu extra_elems
into two independent parts: reuse the per-cpu extra_elems with bucket
lock being held and refill the old_element as per-cpu extra_elems after
the bucket lock is unlocked. However, it will make the concurrent
overwrite procedures on the same CPU return unexpected -E2BIG error when
the map is full.

Therefore, the patch fixes the lock problem by breaking the cancelling
of bpf_timer into two steps for PREEMPT_RT:
1) use hrtimer_try_to_cancel() and check its return value
2) if the timer is running, use hrtimer_cancel() through a kworker to
   cancel it again
Considering that the current implementation of hrtimer_cancel() will try
to acquire a being held softirq_expiry_lock when the current timer is
running, these steps above are reasonable. However, it also has
downside. When the timer is running, the cancelling of the timer is
delayed when releasing the last map uref. The delay is also fixable
(e.g., break the cancelling of bpf timer into two parts: one part in
locked scope, another one in unlocked scope), it can be revised later if
necessary.

It is a bit hard to decide the right fix tag. One reason is that the
problem depends on PREEMPT_RT which is enabled in v6.12. Considering the
softirq_expiry_lock lock exists since v5.4 and bpf_timer is introduced
in v5.15, the bpf_timer commit is used in the fixes tag and an extra
depends-on tag is added to state the dependency on PREEMPT_RT.

Fixes: b00628b ("bpf: Introduce bpf timers.")
Depends-on: v6.12+ with PREEMPT_RT enabled
Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Closes: https://lore.kernel.org/bpf/20241106084527.4gPrMnHt@linutronix.de
Signed-off-by: Hou Tao <houtao1@huawei.com>
Reviewed-by: Toke Høiland-Jørgensen <toke@kernel.org>
Link: https://lore.kernel.org/r/20250117101816.2101857-5-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
norov pushed a commit that referenced this pull request Jan 28, 2025
Hou Tao says:

====================
The patch set continues the previous work [1] to move all the freeings
of htab elements out of bucket lock. One motivation for the patch set is
the locking problem reported by Sebastian [2]: the freeing of bpf_timer
under PREEMPT_RT may acquire a spin-lock (namely softirq_expiry_lock).
However the freeing procedure for htab element has already held a
raw-spin-lock (namely bucket lock), and it will trigger the warning:
"BUG: scheduling while atomic" as demonstrated by the selftests patch.
Another motivation is to reduce the locked scope of bucket lock.

However, the patch set doesn't move all freeing of htab element out of
bucket lock, it still keep the free of special fields in pre-allocated
hash map under the protect of bucket lock in htab_map_update_elem(). The
patch set is structured as follows:

* Patch #1 moves the element freeing out of bucket lock for
  htab_lru_map_delete_node(). However the freeing is still in the locked
  scope of LRU raw spin lock.
* Patch #2~#3 move the element freeing out of bucket lock for
  __htab_map_lookup_and_delete_elem()
* Patch #4 cancels the bpf_timer in two steps to fix the locking
  problem in htab_map_update_elem() for PREEMPT_PRT.
* Patch #5 adds a selftest for the locking problem

Please see individual patches for more details. Comments are always
welcome.
---

v3:
 * patch #1: update the commit message to state that the freeing of
   special field is still in the locked scope of LRU raw spin lock
 * patch #4: cancel the bpf_timer in two steps only for PREEMPT_RT
   (suggested by Alexei)

v2: https://lore.kernel.org/bpf/20250109061901.2620825-1-houtao@huaweicloud.com
  * cancels the bpf timer in two steps instead of breaking the reuse
    the refill of per-cpu ->extra_elems into two steps

v1: https://lore.kernel.org/bpf/20250107085559.3081563-1-houtao@huaweicloud.com

[1]: https://lore.kernel.org/bpf/20241106063542.357743-1-houtao@huaweicloud.com
[2]: https://lore.kernel.org/bpf/20241106084527.4gPrMnHt@linutronix.de
====================

Link: https://patch.msgid.link/20250117101816.2101857-1-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
norov pushed a commit that referenced this pull request Jan 28, 2025
Prevent double queueing of implicit ODP mr destroy work by using
__xa_cmpxchg() to make sure this is the only time we are destroying this
specific mr.

Without this change, we could try to invalidate this mr twice, which in
turn could result in queuing a MR work destroy twice, and eventually the
second work could execute after the MR was freed due to the first work,
causing a user after free and trace below.

   refcount_t: underflow; use-after-free.
   WARNING: CPU: 2 PID: 12178 at lib/refcount.c:28 refcount_warn_saturate+0x12b/0x130
   Modules linked in: bonding ib_ipoib vfio_pci ip_gre geneve nf_tables ip6_gre gre ip6_tunnel tunnel6 ipip tunnel4 ib_umad rdma_ucm mlx5_vfio_pci vfio_pci_core vfio_iommu_type1 mlx5_ib vfio ib_uverbs mlx5_core iptable_raw openvswitch nsh rpcrdma ib_iser libiscsi scsi_transport_iscsi rdma_cm iw_cm ib_cm ib_core xt_conntrack xt_MASQUERADE nf_conntrack_netlink nfnetlink xt_addrtype iptable_nat nf_nat br_netfilter rpcsec_gss_krb5 auth_rpcgss oid_registry overlay zram zsmalloc fuse [last unloaded: ib_uverbs]
   CPU: 2 PID: 12178 Comm: kworker/u20:5 Not tainted 6.5.0-rc1_net_next_mlx5_58c644e #1
   Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
   Workqueue: events_unbound free_implicit_child_mr_work [mlx5_ib]
   RIP: 0010:refcount_warn_saturate+0x12b/0x130
   Code: 48 c7 c7 38 95 2a 82 c6 05 bc c6 fe 00 01 e8 0c 66 aa ff 0f 0b 5b c3 48 c7 c7 e0 94 2a 82 c6 05 a7 c6 fe 00 01 e8 f5 65 aa ff <0f> 0b 5b c3 90 8b 07 3d 00 00 00 c0 74 12 83 f8 01 74 13 8d 50 ff
   RSP: 0018:ffff8881008e3e40 EFLAGS: 00010286
   RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000027
   RDX: ffff88852c91b5c8 RSI: 0000000000000001 RDI: ffff88852c91b5c0
   RBP: ffff8881dacd4e00 R08: 00000000ffffffff R09: 0000000000000019
   R10: 000000000000072e R11: 0000000063666572 R12: ffff88812bfd9e00
   R13: ffff8881c792d200 R14: ffff88810011c005 R15: ffff8881002099c0
   FS:  0000000000000000(0000) GS:ffff88852c900000(0000) knlGS:0000000000000000
   CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
   CR2: 00007f5694b5e000 CR3: 00000001153f6003 CR4: 0000000000370ea0
   DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
   DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
   Call Trace:
    <TASK>
    ? refcount_warn_saturate+0x12b/0x130
    free_implicit_child_mr_work+0x180/0x1b0 [mlx5_ib]
    process_one_work+0x1cc/0x3c0
    worker_thread+0x218/0x3c0
    kthread+0xc6/0xf0
    ret_from_fork+0x1f/0x30
    </TASK>

Fixes: 5256edc ("RDMA/mlx5: Rework implicit ODP destroy")
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/r/c96b8645a81085abff739e6b06e286a350d1283d.1737274283.git.leon@kernel.org
Signed-off-by: Patrisious Haddad <phaddad@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
norov pushed a commit that referenced this pull request Jan 28, 2025
The following failure was reported on HPE ProLiant D320:

[   10.693310][    T1] tpm_tis STM0925:00: 2.0 TPM (device-id 0x3, rev-id 0)
[   10.848132][    T1] ------------[ cut here ]------------
[   10.853559][    T1] WARNING: CPU: 59 PID: 1 at mm/page_alloc.c:4727 __alloc_pages_noprof+0x2ca/0x330
[   10.862827][    T1] Modules linked in:
[   10.866671][    T1] CPU: 59 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.12.0-lp155.2.g52785e2-default #1 openSUSE Tumbleweed (unreleased) 588cd98293a7c9eba9013378d807364c088c9375
[   10.882741][    T1] Hardware name: HPE ProLiant DL320 Gen12/ProLiant DL320 Gen12, BIOS 1.20 10/28/2024
[   10.892170][    T1] RIP: 0010:__alloc_pages_noprof+0x2ca/0x330
[   10.898103][    T1] Code: 24 08 e9 4a fe ff ff e8 34 36 fa ff e9 88 fe ff ff 83 fe 0a 0f 86 b3 fd ff ff 80 3d 01 e7 ce 01 00 75 09 c6 05 f8 e6 ce 01 01 <0f> 0b 45 31 ff e9 e5 fe ff ff f7 c2 00 00 08 00 75 42 89 d9 80 e1
[   10.917750][    T1] RSP: 0000:ffffb7cf40077980 EFLAGS: 00010246
[   10.923777][    T1] RAX: 0000000000000000 RBX: 0000000000040cc0 RCX: 0000000000000000
[   10.931727][    T1] RDX: 0000000000000000 RSI: 000000000000000c RDI: 0000000000040cc0

The above transcript shows that ACPI pointed a 16 MiB buffer for the log
events because RSI maps to the 'order' parameter of __alloc_pages_noprof().
Address the bug by moving from devm_kmalloc() to devm_add_action() and
kvmalloc() and devm_add_action().

Suggested-by: Ard Biesheuvel <ardb@kernel.org>
Cc: stable@vger.kernel.org # v2.6.16+
Fixes: 55a82ab ("[PATCH] tpm: add bios measurement log")
Reported-by: Andy Liang <andy.liang@hpe.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219495
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Andy Liang <andy.liang@hpe.com>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
norov pushed a commit that referenced this pull request Jan 28, 2025
In commit e4b5ccd ("drm/v3d: Ensure job pointer is set to NULL
after job completion"), we introduced a change to assign the job pointer
to NULL after completing a job, indicating job completion.

However, this approach created a race condition between the DRM
scheduler workqueue and the IRQ execution thread. As soon as the fence is
signaled in the IRQ execution thread, a new job starts to be executed.
This results in a race condition where the IRQ execution thread sets the
job pointer to NULL simultaneously as the `run_job()` function assigns
a new job to the pointer.

This race condition can lead to a NULL pointer dereference if the IRQ
execution thread sets the job pointer to NULL after `run_job()` assigns
it to the new job. When the new job completes and the GPU emits an
interrupt, `v3d_irq()` is triggered, potentially causing a crash.

[  466.310099] Unable to handle kernel NULL pointer dereference at virtual address 00000000000000c0
[  466.318928] Mem abort info:
[  466.321723]   ESR = 0x0000000096000005
[  466.325479]   EC = 0x25: DABT (current EL), IL = 32 bits
[  466.330807]   SET = 0, FnV = 0
[  466.333864]   EA = 0, S1PTW = 0
[  466.337010]   FSC = 0x05: level 1 translation fault
[  466.341900] Data abort info:
[  466.344783]   ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000
[  466.350285]   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
[  466.355350]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
[  466.360677] user pgtable: 4k pages, 39-bit VAs, pgdp=0000000089772000
[  466.367140] [00000000000000c0] pgd=0000000000000000, p4d=0000000000000000, pud=0000000000000000
[  466.375875] Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP
[  466.382163] Modules linked in: rfcomm snd_seq_dummy snd_hrtimer snd_seq snd_seq_device algif_hash algif_skcipher af_alg bnep binfmt_misc vc4 snd_soc_hdmi_codec drm_display_helper cec brcmfmac_wcc spidev rpivid_hevc(C) drm_client_lib brcmfmac hci_uart drm_dma_helper pisp_be btbcm brcmutil snd_soc_core aes_ce_blk v4l2_mem2mem bluetooth aes_ce_cipher snd_compress videobuf2_dma_contig ghash_ce cfg80211 gf128mul snd_pcm_dmaengine videobuf2_memops ecdh_generic sha2_ce ecc videobuf2_v4l2 snd_pcm v3d sha256_arm64 rfkill videodev snd_timer sha1_ce libaes gpu_sched snd videobuf2_common sha1_generic drm_shmem_helper mc rp1_pio drm_kms_helper raspberrypi_hwmon spi_bcm2835 gpio_keys i2c_brcmstb rp1 raspberrypi_gpiomem rp1_mailbox rp1_adc nvmem_rmem uio_pdrv_genirq uio i2c_dev drm ledtrig_pattern drm_panel_orientation_quirks backlight fuse dm_mod ip_tables x_tables ipv6
[  466.458429] CPU: 0 UID: 1000 PID: 2008 Comm: chromium Tainted: G         C         6.13.0-v8+ torvalds#18
[  466.467336] Tainted: [C]=CRAP
[  466.470306] Hardware name: Raspberry Pi 5 Model B Rev 1.0 (DT)
[  466.476157] pstate: 404000c9 (nZcv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[  466.483143] pc : v3d_irq+0x118/0x2e0 [v3d]
[  466.487258] lr : __handle_irq_event_percpu+0x60/0x228
[  466.492327] sp : ffffffc080003ea0
[  466.495646] x29: ffffffc080003ea0 x28: ffffff80c0c94200 x27: 0000000000000000
[  466.502807] x26: ffffffd08dd81d7b x25: ffffff80c0c94200 x24: ffffff8003bdc200
[  466.509969] x23: 0000000000000001 x22: 00000000000000a7 x21: 0000000000000000
[  466.517130] x20: ffffff8041bb0000 x19: 0000000000000001 x18: 0000000000000000
[  466.524291] x17: ffffffafadfb0000 x16: ffffffc080000000 x15: 0000000000000000
[  466.531452] x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000
[  466.538613] x11: 0000000000000000 x10: 0000000000000000 x9 : ffffffd08c527eb0
[  466.545777] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
[  466.552941] x5 : ffffffd08c4100d0 x4 : ffffffafadfb0000 x3 : ffffffc080003f70
[  466.560102] x2 : ffffffc0829e8058 x1 : 0000000000000001 x0 : 0000000000000000
[  466.567263] Call trace:
[  466.569711]  v3d_irq+0x118/0x2e0 [v3d] (P)
[  466.573826]  __handle_irq_event_percpu+0x60/0x228
[  466.578546]  handle_irq_event+0x54/0xb8
[  466.582391]  handle_fasteoi_irq+0xac/0x240
[  466.586498]  generic_handle_domain_irq+0x34/0x58
[  466.591128]  gic_handle_irq+0x48/0xd8
[  466.594798]  call_on_irq_stack+0x24/0x58
[  466.598730]  do_interrupt_handler+0x88/0x98
[  466.602923]  el0_interrupt+0x44/0xc0
[  466.606508]  __el0_irq_handler_common+0x18/0x28
[  466.611050]  el0t_64_irq_handler+0x10/0x20
[  466.615156]  el0t_64_irq+0x198/0x1a0
[  466.618740] Code: 52800035 3607faf3 f9442e80 52800021 (f9406018)
[  466.624853] ---[ end trace 0000000000000000 ]---
[  466.629483] Kernel panic - not syncing: Oops: Fatal exception in interrupt
[  466.636384] SMP: stopping secondary CPUs
[  466.640320] Kernel Offset: 0x100c400000 from 0xffffffc080000000
[  466.646259] PHYS_OFFSET: 0x0
[  466.649141] CPU features: 0x100,00000170,00901250,0200720b
[  466.654644] Memory Limit: none
[  466.657706] ---[ end Kernel panic - not syncing: Oops: Fatal exception in interrupt ]---

Fix the crash by assigning the job pointer to NULL before signaling the
fence. This ensures that the job pointer is cleared before any new job
starts execution, preventing the race condition and the NULL pointer
dereference crash.

Cc: stable@vger.kernel.org
Fixes: e4b5ccd ("drm/v3d: Ensure job pointer is set to NULL after job completion")
Signed-off-by: Maíra Canal <mcanal@igalia.com>
Reviewed-by: Jose Maria Casanova Crespo <jmcasanova@igalia.com>
Reviewed-by: Iago Toral Quiroga <itoral@igalia.com>
Tested-by: Phil Elwell <phil@raspberrypi.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250123012403.20447-1-mcanal@igalia.com
norov pushed a commit that referenced this pull request Jan 28, 2025
When testing the atomic write fix patches, the f2fs_bug_on was
triggered as below:

------------[ cut here ]------------
kernel BUG at fs/f2fs/inode.c:935!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP PTI
CPU: 3 UID: 0 PID: 257 Comm: bash Not tainted 6.13.0-rc1-00033-gc283a70d3497 #5
RIP: 0010:f2fs_evict_inode+0x50f/0x520
Call Trace:
 <TASK>
 ? __die_body+0x65/0xb0
 ? die+0x9f/0xc0
 ? do_trap+0xa1/0x170
 ? f2fs_evict_inode+0x50f/0x520
 ? f2fs_evict_inode+0x50f/0x520
 ? handle_invalid_op+0x65/0x80
 ? f2fs_evict_inode+0x50f/0x520
 ? exc_invalid_op+0x39/0x50
 ? asm_exc_invalid_op+0x1a/0x20
 ? __pfx_f2fs_get_dquots+0x10/0x10
 ? f2fs_evict_inode+0x50f/0x520
 ? f2fs_evict_inode+0x2e5/0x520
 evict+0x186/0x2f0
 prune_icache_sb+0x75/0xb0
 super_cache_scan+0x1a8/0x200
 do_shrink_slab+0x163/0x320
 shrink_slab+0x2fc/0x470
 drop_slab+0x82/0xf0
 drop_caches_sysctl_handler+0x4e/0xb0
 proc_sys_call_handler+0x183/0x280
 vfs_write+0x36d/0x450
 ksys_write+0x68/0xd0
 do_syscall_64+0xc8/0x1a0
 ? arch_exit_to_user_mode_prepare+0x11/0x60
 ? irqentry_exit_to_user_mode+0x7e/0xa0

The root cause is: f2fs uses FI_ATOMIC_DIRTIED to indicate dirty
atomic files during commit. If the inode is dirtied during commit,
such as by f2fs_i_pino_write, the vfs inode keeps clean and the
f2fs inode is set to FI_DIRTY_INODE. The FI_DIRTY_INODE flag cann't
be cleared by write_inode later due to the clean vfs inode. Finally,
f2fs_bug_on is triggered due to this inconsistent state when evict.

To reproduce this situation:
- fd = open("/mnt/test.db", O_WRONLY)
- ioctl(fd, F2FS_IOC_START_ATOMIC_WRITE)
- mv /mnt/test.db /mnt/test1.db
- ioctl(fd, F2FS_IOC_COMMIT_ATOMIC_WRITE)
- echo 3 > /proc/sys/vm/drop_caches

To fix this problem, clear FI_DIRTY_INODE after commit, then
f2fs_mark_inode_dirty_sync will ensure a consistent dirty state.

Fixes: fccaa81 ("f2fs: prevent atomic file from being dirtied before commit")
Signed-off-by: Yunlei He <heyunlei@xiaomi.com>
Signed-off-by: Jianan Huang <huangjianan@xiaomi.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
norov pushed a commit that referenced this pull request Jan 28, 2025
…g_info

syz reported:

(syz-executor404,5313,0):ocfs2_truncate_log_append:5874 ERROR: bug
expression: tl_count > ocfs2_truncate_recs_per_inode(osb->sb) ||
tl_count == 0
(syz-executor404,5313,0):ocfs2_truncate_log_append:5874 ERROR: Truncate
record count on torvalds#77 invalid wanted 39, actual 2087
------------[ cut here  ]------------
kernel BUG at fs/ocfs2/alloc.c:5874!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5313 Comm: syz-executor404 Not tainted
6.12.0-rc5-syzkaller-00299-g11066801dd4b #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:ocfs2_truncate_log_append+0x9a8/0x9c0 fs/ocfs2/alloc.c:5868
RSP: 0018:ffffc9000cf16f40 EFLAGS: 00010292
RAX: b4b54f1d10640800 RBX: 0000000000000027 RCX: b4b54f1d10640800
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: ffffc9000cf17070 R08: ffffffff8174a14c R09: 1ffff11003f8519a
R10: dffffc0000000000 R11: ffffed1003f8519b R12: 1ffff110085f5f58
R13: ffffff3800000000 R14: 000000000000004d R15: ffff8880438f0008
FS:  00005555722df380(0000) GS:ffff88801fc00000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002000f000 CR3: 000000004010e000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
ocfs2_remove_btree_range+0x1303/0x1860 fs/ocfs2/alloc.c:5789
ocfs2_remove_inode_range+0xff3/0x29f0 fs/ocfs2/file.c:1907
ocfs2_reflink_remap_extent fs/ocfs2/refcounttree.c:4537 [inline]
ocfs2_reflink_remap_blocks+0xcd4/0x1f30 fs/ocfs2/refcounttree.c:4684
ocfs2_remap_file_range+0x5fa/0x8d0 fs/ocfs2/file.c:2736
vfs_copy_file_range+0xc07/0x1510 fs/read_write.c:1615
__do_sys_copy_file_range fs/read_write.c:1705 [inline]
__se_sys_copy_file_range+0x3f2/0x5d0 fs/read_write.c:1668
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd327167af9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 61 17 00 00 90 48 89 f8 48 89
f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01
f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe6b8e22e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000146
RAX: ffffffffffffffda RBX: 00007fd3271b005e RCX: 00007fd327167af9
RDX: 0000000000000006 RSI: 0000000000000000 RDI: 0000000000000004
RBP: 00007fd3271de610 R08: 000000000000d8c2 R09: 0000000000000000
R10: 0000000020000640 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffe6b8e24b8 R14: 0000000000000001 R15: 0000000000000001
</TASK>

The fuzz image has a truncate log inode whose tl_count is bigger than
ocfs2_truncate_recs_per_inode() so it triggers the BUG in
ocfs2_truncate_log_append().

As what the check in ocfs2_truncate_log_append() does, just do same check
into ocfs2_get_truncate_log_info when truncate log inode is reading in so
we can bail out earlier.

Link: https://lkml.kernel.org/r/20250108024119.60313-1-glass.su@suse.com
Signed-off-by: Su Yue <glass.su@suse.com>
Reported-by: Liebes Wang <wanghaichi0403@gmail.com>
Link: https://lore.kernel.org/ocfs2-devel/CADCV8souQhdP0RdQF1U7KTWtuHDfpn+3LnTt-EEuMmB-pMRrgQ@mail.gmail.com/T/#u
Reported-by: syzbot+a66542ca5ebb4233b563@syzkaller.appspotmail.com
Tested-by: syzbot+a66542ca5ebb4233b563@syzkaller.appspotmail.com
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
norov pushed a commit that referenced this pull request Feb 3, 2025
Packets handled by hardware have added secpath as a way to inform XFRM
core code that this path was already handled. That secpath is not needed
at all after policy is checked and it is removed later in the stack.

However, in the case of IP forwarding is enabled (/proc/sys/net/ipv4/ip_forward),
that secpath is not removed and packets which already were handled are reentered
to the driver TX path with xfrm_offload set.

The following kernel panic is observed in mlx5 in such case:

 mlx5_core 0000:04:00.0 enp4s0f0np0: Link up
 mlx5_core 0000:04:00.1 enp4s0f1np1: Link up
 Initializing XFRM netlink socket
 IPsec XFRM device driver
 BUG: kernel NULL pointer dereference, address: 0000000000000000
 #PF: supervisor instruction fetch in kernel mode
 #PF: error_code(0x0010) - not-present page
 PGD 0 P4D 0
 Oops: Oops: 0010 [#1] PREEMPT SMP
 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.13.0-rc1-alex #3
 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-1ubuntu1.1 04/01/2014
 RIP: 0010:0x0
 Code: Unable to access opcode bytes at 0xffffffffffffffd6.
 RSP: 0018:ffffb87380003800 EFLAGS: 00010206
 RAX: ffff8df004e02600 RBX: ffffb873800038d8 RCX: 00000000ffff98cf
 RDX: ffff8df00733e108 RSI: ffff8df00521fb80 RDI: ffff8df001661f00
 RBP: ffffb87380003850 R08: ffff8df013980000 R09: 0000000000000010
 R10: 0000000000000002 R11: 0000000000000002 R12: ffff8df001661f00
 R13: ffff8df00521fb80 R14: ffff8df00733e108 R15: ffff8df011faf04e
 FS:  0000000000000000(0000) GS:ffff8df46b800000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: ffffffffffffffd6 CR3: 0000000106384000 CR4: 0000000000350ef0
 Call Trace:
  <IRQ>
  ? show_regs+0x63/0x70
  ? __die_body+0x20/0x60
  ? __die+0x2b/0x40
  ? page_fault_oops+0x15c/0x550
  ? do_user_addr_fault+0x3ed/0x870
  ? exc_page_fault+0x7f/0x190
  ? asm_exc_page_fault+0x27/0x30
  mlx5e_ipsec_handle_tx_skb+0xe7/0x2f0 [mlx5_core]
  mlx5e_xmit+0x58e/0x1980 [mlx5_core]
  ? __fib_lookup+0x6a/0xb0
  dev_hard_start_xmit+0x82/0x1d0
  sch_direct_xmit+0xfe/0x390
  __dev_queue_xmit+0x6d8/0xee0
  ? __fib_lookup+0x6a/0xb0
  ? internal_add_timer+0x48/0x70
  ? mod_timer+0xe2/0x2b0
  neigh_resolve_output+0x115/0x1b0
  __neigh_update+0x26a/0xc50
  neigh_update+0x14/0x20
  arp_process+0x2cb/0x8e0
  ? __napi_build_skb+0x5e/0x70
  arp_rcv+0x11e/0x1c0
  ? dev_gro_receive+0x574/0x820
  __netif_receive_skb_list_core+0x1cf/0x1f0
  netif_receive_skb_list_internal+0x183/0x2a0
  napi_complete_done+0x76/0x1c0
  mlx5e_napi_poll+0x234/0x7a0 [mlx5_core]
  __napi_poll+0x2d/0x1f0
  net_rx_action+0x1a6/0x370
  ? atomic_notifier_call_chain+0x3b/0x50
  ? irq_int_handler+0x15/0x20 [mlx5_core]
  handle_softirqs+0xb9/0x2f0
  ? handle_irq_event+0x44/0x60
  irq_exit_rcu+0xdb/0x100
  common_interrupt+0x98/0xc0
  </IRQ>
  <TASK>
  asm_common_interrupt+0x27/0x40
 RIP: 0010:pv_native_safe_halt+0xb/0x10
 Code: 09 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 0f 22
 0f 1f 84 00 00 00 00 00 90 eb 07 0f 00 2d 7f e9 36 00 fb
40 00 83 ff 07 77 21 89 ff ff 24 fd 88 3d a1 bd 0f 21 f8
 RSP: 0018:ffffffffbe603de8 EFLAGS: 00000202
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000f92f46680
 RDX: 0000000000000037 RSI: 00000000ffffffff RDI: 00000000000518d4
 RBP: ffffffffbe603df0 R08: 000000cd42e4dffb R09: ffffffffbe603d70
 R10: 0000004d80d62680 R11: 0000000000000001 R12: ffffffffbe60bf40
 R13: 0000000000000000 R14: 0000000000000000 R15: ffffffffbe60aff8
  ? default_idle+0x9/0x20
  arch_cpu_idle+0x9/0x10
  default_idle_call+0x29/0xf0
  do_idle+0x1f2/0x240
  cpu_startup_entry+0x2c/0x30
  rest_init+0xe7/0x100
  start_kernel+0x76b/0xb90
  x86_64_start_reservations+0x18/0x30
  x86_64_start_kernel+0xc0/0x110
  ? setup_ghcb+0xe/0x130
  common_startup_64+0x13e/0x141
  </TASK>
 Modules linked in: esp4_offload esp4 xfrm_interface
xfrm6_tunnel tunnel4 tunnel6 xfrm_user xfrm_algo binfmt_misc
intel_rapl_msr intel_rapl_common kvm_amd ccp kvm input_leds serio_raw
qemu_fw_cfg sch_fq_codel dm_multipath scsi_dh_rdac scsi_dh_emc
scsi_dh_alua efi_pstore ip_tables x_tables autofs4 raid10 raid456
async_raid6_recov async_memcpy async_pq raid6_pq async_xor xor async_tx
libcrc32c raid1 raid0 mlx5_core crct10dif_pclmul crc32_pclmul
polyval_clmulni polyval_generic ghash_clmulni_intel sha256_ssse3
sha1_ssse3 ahci mlxfw i2c_i801 libahci i2c_mux i2c_smbus psample
virtio_rng pci_hyperv_intf aesni_intel crypto_simd cryptd
 CR2: 0000000000000000
 ---[ end trace 0000000000000000 ]---
 RIP: 0010:0x0
 Code: Unable to access opcode bytes at 0xffffffffffffffd6.
 RSP: 0018:ffffb87380003800 EFLAGS: 00010206
 RAX: ffff8df004e02600 RBX: ffffb873800038d8 RCX: 00000000ffff98cf
 RDX: ffff8df00733e108 RSI: ffff8df00521fb80 RDI: ffff8df001661f00
 RBP: ffffb87380003850 R08: ffff8df013980000 R09: 0000000000000010
 R10: 0000000000000002 R11: 0000000000000002 R12: ffff8df001661f00
 R13: ffff8df00521fb80 R14: ffff8df00733e108 R15: ffff8df011faf04e
 FS:  0000000000000000(0000) GS:ffff8df46b800000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: ffffffffffffffd6 CR3: 0000000106384000 CR4: 0000000000350ef0
 Kernel panic - not syncing: Fatal exception in interrupt
 Kernel Offset: 0x3b800000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
 ---[ end Kernel panic - not syncing: Fatal exception in interrupt ]---

Fixes: 5958372 ("xfrm: add RX datapath protection for IPsec packet offload mode")
Signed-off-by: Alexandre Cassen <acassen@corp.free.fr>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
norov pushed a commit that referenced this pull request Feb 3, 2025
On pSeries, when user attempts to use the same vfio container used by
different iommu group, the spapr_tce_set_window() returns -EPERM
and the subsequent cleanup leads to the below crash.

   Kernel attempted to read user page (308) - exploit attempt?
   BUG: Kernel NULL pointer dereference on read at 0x00000308
   Faulting instruction address: 0xc0000000001ce358
   Oops: Kernel access of bad area, sig: 11 [#1]
   NIP:  c0000000001ce358 LR: c0000000001ce05c CTR: c00000000005add0
   <snip>
   NIP [c0000000001ce358] spapr_tce_unset_window+0x3b8/0x510
   LR [c0000000001ce05c] spapr_tce_unset_window+0xbc/0x510
   Call Trace:
     spapr_tce_unset_window+0xbc/0x510 (unreliable)
     tce_iommu_attach_group+0x24c/0x340 [vfio_iommu_spapr_tce]
     vfio_container_attach_group+0xec/0x240 [vfio]
     vfio_group_fops_unl_ioctl+0x548/0xb00 [vfio]
     sys_ioctl+0x754/0x1580
     system_call_exception+0x13c/0x330
     system_call_vectored_common+0x15c/0x2ec
   <snip>
   --- interrupt: 3000

Fix this by having null check for the tbl passed to the
spapr_tce_unset_window().

Fixes: f431a8c ("powerpc/iommu: Reimplement the iommu_table_group_ops for pSeries")
Cc: stable@vger.kernel.org
Reported-by: Vaishnavi Bhat <vaish123@in.ibm.com>
Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/173674009556.1559.12487885286848752833.stgit@linux.ibm.com
norov pushed a commit that referenced this pull request Feb 3, 2025
On some systems, the same CPU (with the same APIC ID) is assigned a
different logical CPU id after commit ec9aedb ("x86/acpi: Ignore
invalid x2APIC entries").

This means that Linux enumerates the CPUs in a different order, which
violates ACPI specification[1] that states:

  "OSPM should initialize processors in the order that they appear in
   the MADT"

The problematic commit parses all LAPIC entries before any x2APIC
entries, aiming to ignore x2APIC entries with APIC ID < 255 when valid
LAPIC entries exist. However, it disrupts the CPU enumeration order on
systems where x2APIC entries precede LAPIC entries in the MADT.

Fix this problem by:

 1) Parsing LAPIC entries first without registering them in the
    topology to evaluate whether valid LAPIC entries exist.

 2) Restoring the MADT in order parser which invokes either the LAPIC
    or the X2APIC parser function depending on the entry type.

The X2APIC parser still ignores entries < 0xff in case that #1 found
valid LAPIC entries independent of their position in the MADT table.

Link: https://uefi.org/specs/ACPI/6.5/05_ACPI_Software_Programming_Model.html#madt-processor-local-apic-sapic-structure-entry-order
Cc: All applicable <stable@vger.kernel.org>
Reported-by: Jim Mattson <jmattson@google.com>
Closes: https://lore.kernel.org/all/20241010213136.668672-1-jmattson@google.com/
Fixes: ec9aedb ("x86/acpi: Ignore invalid x2APIC entries")
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Tested-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://patch.msgid.link/20250117081420.4046737-1-rui.zhang@intel.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
norov pushed a commit that referenced this pull request Feb 3, 2025
Add read memory barrier to ensure the order of operations when accessing
control queue descriptors. Specifically, we want to avoid cases where loads
can be reordered:

1. Load #1 is dispatched to read descriptor flags.
2. Load #2 is dispatched to read some other field from the descriptor.
3. Load #2 completes, accessing memory/cache at a point in time when the DD
   flag is zero.
4. NIC DMA overwrites the descriptor, now the DD flag is one.
5. Any fields loaded before step 4 are now inconsistent with the actual
   descriptor state.

Add read memory barrier between steps 1 and 2, so that load #2 is not
executed until load #1 has completed.

Fixes: 8077c72 ("idpf: add controlq init and reset checks")
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Reviewed-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
Suggested-by: Lance Richardson <rlance@google.com>
Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
Tested-by: Krishneil Singh <krishneil.k.singh@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
norov pushed a commit that referenced this pull request Feb 3, 2025
In "one-shot" mode, turbostat
1. takes a counter snapshot
2. forks and waits for a child
3. takes the end counter snapshot and prints the result.

But turbostat counter snapshots currently use affinity to travel
around the system so that counter reads are "local", and this
affinity must be cleared between #1 and #2 above.

The offending commit removed that reset that allowed the child
to run on cpu_present_set.

Fix that issue, and improve upon the original by using
cpu_possible_set for the child.  This allows the child
to also run on CPUs that hotplug online during its runtime.

Reported-by: Zhang Rui <rui.zhang@intel.com>
Fixes: 7bb3fe2 ("tools/power/turbostat: Obey allowed CPUs during startup")
Signed-off-by: Len Brown <len.brown@intel.com>
norov pushed a commit that referenced this pull request Feb 3, 2025
libtraceevent parses and returns an array of argument fields, sometimes
larger than RAW_SYSCALL_ARGS_NUM (6) because it includes "__syscall_nr",
idx will traverse to index 6 (7th element) whereas sc->fmt->arg holds 6
elements max, creating an out-of-bounds access. This runtime error is
found by UBsan. The error message:

  $ sudo UBSAN_OPTIONS=print_stacktrace=1 ./perf trace -a --max-events=1
  builtin-trace.c:1966:35: runtime error: index 6 out of bounds for type 'syscall_arg_fmt [6]'
    #0 0x5c04956be5fe in syscall__alloc_arg_fmts /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:1966
    #1 0x5c04956c0510 in trace__read_syscall_info /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:2110
    #2 0x5c04956c372b in trace__syscall_info /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:2436
    #3 0x5c04956d2f39 in trace__init_syscalls_bpf_prog_array_maps /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:3897
    #4 0x5c04956d6d25 in trace__run /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:4335
    #5 0x5c04956e112e in cmd_trace /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:5502
    torvalds#6 0x5c04956eda7d in run_builtin /home/howard/hw/linux-perf/tools/perf/perf.c:351
    torvalds#7 0x5c04956ee0a8 in handle_internal_command /home/howard/hw/linux-perf/tools/perf/perf.c:404
    torvalds#8 0x5c04956ee37f in run_argv /home/howard/hw/linux-perf/tools/perf/perf.c:448
    torvalds#9 0x5c04956ee8e9 in main /home/howard/hw/linux-perf/tools/perf/perf.c:556
    torvalds#10 0x79eb3622a3b7 in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58
    torvalds#11 0x79eb3622a47a in __libc_start_main_impl ../csu/libc-start.c:360
    torvalds#12 0x5c04955422d4 in _start (/home/howard/hw/linux-perf/tools/perf/perf+0x4e02d4) (BuildId: 5b6cab2d59e96a4341741765ad6914a4d784dbc6)

     0.000 ( 0.014 ms): Chrome_ChildIO/117244 write(fd: 238, buf: !, count: 1)                                      = 1

Fixes: 5e58fcf ("perf trace: Allow allocating sc->arg_fmt even without the syscall tracepoint")
Signed-off-by: Howard Chu <howardchu95@gmail.com>
Link: https://lore.kernel.org/r/20250122025519.361873-1-howardchu95@gmail.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
norov pushed a commit that referenced this pull request Feb 3, 2025
This fixes the following hard lockup in isolate_lru_folios() during memory
reclaim.  If the LRU mostly contains ineligible folios this may trigger
watchdog.

watchdog: Watchdog detected hard LOCKUP on cpu 173
RIP: 0010:native_queued_spin_lock_slowpath+0x255/0x2a0
Call Trace:
	_raw_spin_lock_irqsave+0x31/0x40
	folio_lruvec_lock_irqsave+0x5f/0x90
	folio_batch_move_lru+0x91/0x150
	lru_add_drain_per_cpu+0x1c/0x40
	process_one_work+0x17d/0x350
	worker_thread+0x27b/0x3a0
	kthread+0xe8/0x120
	ret_from_fork+0x34/0x50
	ret_from_fork_asm+0x1b/0x30

lruvec->lru_lock owner:

PID: 2865     TASK: ffff888139214d40  CPU: 40   COMMAND: "kswapd0"
 #0 [fffffe0000945e60] crash_nmi_callback at ffffffffa567a555
 #1 [fffffe0000945e68] nmi_handle at ffffffffa563b171
 #2 [fffffe0000945eb0] default_do_nmi at ffffffffa6575920
 #3 [fffffe0000945ed0] exc_nmi at ffffffffa6575af4
 #4 [fffffe0000945ef0] end_repeat_nmi at ffffffffa6601dde
    [exception RIP: isolate_lru_folios+403]
    RIP: ffffffffa597df53  RSP: ffffc90006fb7c28  RFLAGS: 00000002
    RAX: 0000000000000001  RBX: ffffc90006fb7c60  RCX: ffffea04a2196f88
    RDX: ffffc90006fb7c60  RSI: ffffc90006fb7c60  RDI: ffffea04a2197048
    RBP: ffff88812cbd3010   R8: ffffea04a2197008   R9: 0000000000000001
    R10: 0000000000000000  R11: 0000000000000001  R12: ffffea04a2197008
    R13: ffffea04a2197048  R14: ffffc90006fb7de8  R15: 0000000003e3e937
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
    <NMI exception stack>
 #5 [ffffc90006fb7c28] isolate_lru_folios at ffffffffa597df53
 torvalds#6 [ffffc90006fb7cf8] shrink_active_list at ffffffffa597f788
 torvalds#7 [ffffc90006fb7da8] balance_pgdat at ffffffffa5986db0
 torvalds#8 [ffffc90006fb7ec0] kswapd at ffffffffa5987354
 torvalds#9 [ffffc90006fb7ef8] kthread at ffffffffa5748238
crash>

Scenario:
User processe are requesting a large amount of memory and keep page active.
Then a module continuously requests memory from ZONE_DMA32 area.
Memory reclaim will be triggered due to ZONE_DMA32 watermark alarm reached.
However pages in the LRU(active_anon) list are mostly from
the ZONE_NORMAL area.

Reproduce:
Terminal 1: Construct to continuously increase pages active(anon).
mkdir /tmp/memory
mount -t tmpfs -o size=1024000M tmpfs /tmp/memory
dd if=/dev/zero of=/tmp/memory/block bs=4M
tail /tmp/memory/block

Terminal 2:
vmstat -a 1
active will increase.
procs ---memory--- ---swap-- ---io---- -system-- ---cpu--- ...
 r  b   swpd   free  inact active   si   so    bi    bo
 1  0   0 1445623076 45898836 83646008    0    0     0
 1  0   0 1445623076 43450228 86094616    0    0     0
 1  0   0 1445623076 41003480 88541364    0    0     0
 1  0   0 1445623076 38557088 90987756    0    0     0
 1  0   0 1445623076 36109688 93435156    0    0     0
 1  0   0 1445619552 33663256 95881632    0    0     0
 1  0   0 1445619804 31217140 98327792    0    0     0
 1  0   0 1445619804 28769988 100774944    0    0     0
 1  0   0 1445619804 26322348 103222584    0    0     0
 1  0   0 1445619804 23875592 105669340    0    0     0

cat /proc/meminfo | head
Active(anon) increase.
MemTotal:       1579941036 kB
MemFree:        1445618500 kB
MemAvailable:   1453013224 kB
Buffers:            6516 kB
Cached:         128653956 kB
SwapCached:            0 kB
Active:         118110812 kB
Inactive:       11436620 kB
Active(anon):   115345744 kB
Inactive(anon):   945292 kB

When the Active(anon) is 115345744 kB, insmod module triggers
the ZONE_DMA32 watermark.

perf record -e vmscan:mm_vmscan_lru_isolate -aR
perf script
isolate_mode=0 classzone=1 order=1 nr_requested=32 nr_scanned=2
nr_skipped=2 nr_taken=0 lru=active_anon
isolate_mode=0 classzone=1 order=1 nr_requested=32 nr_scanned=0
nr_skipped=0 nr_taken=0 lru=active_anon
isolate_mode=0 classzone=1 order=0 nr_requested=32 nr_scanned=28835844
nr_skipped=28835844 nr_taken=0 lru=active_anon
isolate_mode=0 classzone=1 order=1 nr_requested=32 nr_scanned=28835844
nr_skipped=28835844 nr_taken=0 lru=active_anon
isolate_mode=0 classzone=1 order=0 nr_requested=32 nr_scanned=29
nr_skipped=29 nr_taken=0 lru=active_anon
isolate_mode=0 classzone=1 order=0 nr_requested=32 nr_scanned=0
nr_skipped=0 nr_taken=0 lru=active_anon

See nr_scanned=28835844.
28835844 * 4k = 115343376KB approximately equal to 115345744 kB.

If increase Active(anon) to 1000G then insmod module triggers
the ZONE_DMA32 watermark. hard lockup will occur.

In my device nr_scanned = 0000000003e3e937 when hard lockup.
Convert to memory size 0x0000000003e3e937 * 4KB = 261072092 KB.

   [ffffc90006fb7c28] isolate_lru_folios at ffffffffa597df53
    ffffc90006fb7c30: 0000000000000020 0000000000000000
    ffffc90006fb7c40: ffffc90006fb7d40 ffff88812cbd3000
    ffffc90006fb7c50: ffffc90006fb7d30 0000000106fb7de8
    ffffc90006fb7c60: ffffea04a2197008 ffffea0006ed4a48
    ffffc90006fb7c70: 0000000000000000 0000000000000000
    ffffc90006fb7c80: 0000000000000000 0000000000000000
    ffffc90006fb7c90: 0000000000000000 0000000000000000
    ffffc90006fb7ca0: 0000000000000000 0000000003e3e937
    ffffc90006fb7cb0: 0000000000000000 0000000000000000
    ffffc90006fb7cc0: 8d7c0b56b7874b00 ffff88812cbd3000

About the Fixes:
Why did it take eight years to be discovered?

The problem requires the following conditions to occur:
1. The device memory should be large enough.
2. Pages in the LRU(active_anon) list are mostly from the ZONE_NORMAL area.
3. The memory in ZONE_DMA32 needs to reach the watermark.

If the memory is not large enough, or if the usage design of ZONE_DMA32
area memory is reasonable, this problem is difficult to detect.

notes:
The problem is most likely to occur in ZONE_DMA32 and ZONE_NORMAL,
but other suitable scenarios may also trigger the problem.

Link: https://lkml.kernel.org/r/20241119060842.274072-1-liuye@kylinos.cn
Fixes: b2e1875 ("mm, vmscan: begin reclaiming pages on a per-node basis")
Signed-off-by: liuye <liuye@kylinos.cn>
Cc: Hugh Dickins <hughd@google.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Yang Shi <yang@os.amperecomputing.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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