[v5.15] INFO: rcu detected stall in kernfs_fop_release

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: fa93fa65db6e Linux 5.15.165
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=16b6c625980000
kernel config: https://syzkaller.appspot.com/x/.config?x=d027d7ba4e9e9586
dashboard link: https://syzkaller.appspot.com/bug?extid=8cd4e555eeab29a91f87
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/7401830de8b7/disk-fa93fa65.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/55f1128c249c/vmlinux-fa93fa65.xz
kernel image: https://storage.googleapis.com/syzbot-assets/5ce80d349162/bzImage-fa93fa65.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+8cd4e5...@syzkaller.appspotmail.com

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P3028/1:b..l
(detected by 1, t=10502 jiffies, g=10589, q=300)
task:udevd state:R running task stack:24512 pid: 3028 ppid: 1 flags:0x00004002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5027 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6777
irqentry_exit+0x53/0x80 kernel/entry/common.c:432
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:lock_acquire+0x252/0x4f0 kernel/locking/lockdep.c:5627
Code: 2b 00 74 08 4c 89 f7 e8 4c 7b 67 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
RSP: 0018:ffffc90002bf76c0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff9200057eee4 RCX: 1ffff9200057ee84
RDX: dffffc0000000000 RSI: ffffffff8a8b3cc0 RDI: ffffffff8ad8f7c0
RBP: ffffc90002bf7820 R08: dffffc0000000000 R09: fffffbfff1f8e219
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200057eee0
R13: dffffc0000000000 R14: ffffc90002bf7720 R15: 0000000000000246
rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312
rcu_read_lock include/linux/rcupdate.h:739 [inline]
is_bpf_text_address+0x1d/0x260 kernel/bpf/core.c:721
kernel_text_address kernel/extable.c:151 [inline]
__kernel_text_address+0x94/0x100 kernel/extable.c:105
unwind_get_return_address+0x49/0x80 arch/x86/kernel/unwind_orc.c:323
arch_stack_walk+0xf3/0x140 arch/x86/kernel/stacktrace.c:26
stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:38 [inline]
kasan_set_track+0x4b/0x80 mm/kasan/common.c:46
kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360
____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:366
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:1705 [inline]
slab_free_freelist_hook+0xdd/0x160 mm/slub.c:1731
slab_free mm/slub.c:3499 [inline]
kmem_cache_free+0x91/0x1f0 mm/slub.c:3515
seq_release+0x62/0x70 fs/seq_file.c:356
kernfs_fop_release+0x1eb/0x2b0 fs/kernfs/file.c:761
__fput+0x3fe/0x8e0 fs/file_table.c:280
task_work_run+0x129/0x1a0 kernel/task_work.c:188
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:181
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fa5ddc7a37f
RSP: 002b:00007ffda27c0d58 EFLAGS: 00000202 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 000055dd0799ffd0 RCX: 00007fa5ddc7a37f
RDX: 00007fa5ddd4d860 RSI: 0000000000000003 RDI: 000000000000000c
RBP: 0000000000000000 R08: 000000000000000c R09: 0000000000000000
R10: 0000000000000010 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000000000007 R14: 0000000000000003 R15: 000055dd061d2fc1
</TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 5015 jiffies! g10589 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=0 timer-softirq=4892
rcu: rcu_preempt kthread starved for 5016 jiffies! g10589 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt state:I stack:26816 pid: 15 ppid: 2 flags:0x00004000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5027 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
schedule+0x11b/0x1f0 kernel/sched/core.c:6456
schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
kthread+0x3f6/0x4f0 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt drivers/acpi/processor_idle.c:108 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:562


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