[syzbot] possible deadlock in snd_pcm_period_elapsed (3)

syzbot
2021-12-29T01:26:27Z

Hello,

syzbot found the following issue on:

HEAD commit: b927dfc67d05 Merge tag 'for-linus' of git://git.armlinux.o..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10d7f80db00000
kernel config: https://syzkaller.appspot.com/x/.config?x=ec8ccde32929e7ce
dashboard link: https://syzkaller.appspot.com/bug?extid=669c9abf11a6a011dd09
compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.2

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

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+669c9abf11a6a011dd09@syzkaller.appspotmail.com

=====================================================
WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected
5.16.0-rc6-syzkaller #0 Not tainted
-----------------------------------------------------
syz-executor.2/12930 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
ffffffff8c80a058 (tasklist_lock){.+.+}-{2:2}, at: send_sigio+0xbe/0x300 fs/fcntl.c:810

and this task is already holding:
ffff88806efb3cb8 (&f->f_owner.lock){...-}-{2:2}, at: send_sigio+0x2f/0x300 fs/fcntl.c:796
which would create a new lock dependency:
(&f->f_owner.lock){...-}-{2:2} -> (tasklist_lock){.+.+}-{2:2}

but this new dependency connects a SOFTIRQ-irq-safe lock:
(&group->lock){..-.}-{2:2}

... which became SOFTIRQ-irq-safe at:
lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5637
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
snd_pcm_period_elapsed+0x2c/0x210 sound/core/pcm_lib.c:1848
dummy_hrtimer_callback+0x87/0x190 sound/drivers/dummy.c:377
__run_hrtimer kernel/time/hrtimer.c:1685 [inline]
__hrtimer_run_queues+0x50b/0xa60 kernel/time/hrtimer.c:1749
hrtimer_run_softirq+0x1b7/0x5d0 kernel/time/hrtimer.c:1766
__do_softirq+0x392/0x7a3 kernel/softirq.c:558
__irq_exit_rcu+0xec/0x170 kernel/softirq.c:637
irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1097
asm_sysvec_apic_timer_interrupt+0x12/0x20
variable_test_bit arch/x86/include/asm/bitops.h:214 [inline]
test_bit include/asm-generic/bitops/instrumented-non-atomic.h:135 [inline]
cpumask_test_cpu include/linux/cpumask.h:344 [inline]
cpu_online include/linux/cpumask.h:895 [inline]
trace_lock_release+0x39/0x150 include/trace/events/lock.h:58
lock_release+0x82/0x810 kernel/locking/lockdep.c:5648
rcu_read_unlock include/linux/rcupdate.h:721 [inline]
__do_sys_getpriority kernel/sys.c:321 [inline]
__se_sys_getpriority+0x6b1/0x9c0 kernel/sys.c:273
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae

to a SOFTIRQ-irq-unsafe lock:
(tasklist_lock){.+.+}-{2:2}

... which became SOFTIRQ-irq-unsafe at:
...
lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5637
__raw_read_lock include/linux/rwlock_api_smp.h:149 [inline]
_raw_read_lock+0x32/0x40 kernel/locking/spinlock.c:228
do_wait+0x224/0x9d0 kernel/exit.c:1511
kernel_wait+0xe4/0x230 kernel/exit.c:1701
call_usermodehelper_exec_sync kernel/umh.c:139 [inline]
call_usermodehelper_exec_work+0xb4/0x220 kernel/umh.c:166
process_one_work+0x853/0x1140 kernel/workqueue.c:2298
worker_thread+0xac1/0x1320 kernel/workqueue.c:2445
kthread+0x468/0x490 kernel/kthread.c:327
ret_from_fork+0x1f/0x30

other info that might help us debug this:

Chain exists of:
&group->lock --> &f->f_owner.lock --> tasklist_lock

Possible interrupt unsafe locking scenario:

CPU0 CPU1
---- ----
lock(tasklist_lock);
local_irq_disable();
lock(&group->lock);
lock(&f->f_owner.lock);
<Interrupt>
lock(&group->lock);

*** DEADLOCK ***

5 locks held by syz-executor.2/12930:
#0: ffff88807efb4460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:376
#1: ffff8880326621d8 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: inode_lock include/linux/fs.h:783 [inline]
#1: ffff8880326621d8 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: open_last_lookups fs/namei.c:3347 [inline]
#1: ffff8880326621d8 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: path_openat+0x853/0x3660 fs/namei.c:3556
#2: ffffffff90c894f8 (&fsnotify_mark_srcu){....}-{0:0}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:267
#3: ffff888075975038 (&mark->lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:349 [inline]
#3: ffff888075975038 (&mark->lock){+.+.}-{2:2}, at: dnotify_handle_event+0x5d/0x450 fs/notify/dnotify/dnotify.c:89
#4: ffff88806efb3cb8 (&f->f_owner.lock){...-}-{2:2}, at: send_sigio+0x2f/0x300 fs/fcntl.c:796

the dependencies between SOFTIRQ-irq-safe lock and the holding lock:
-> (&group->lock){..-.}-{2:2} {
IN-SOFTIRQ-W at:
lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5637
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
snd_pcm_period_elapsed+0x2c/0x210 sound/core/pcm_lib.c:1848
dummy_hrtimer_callback+0x87/0x190 sound/drivers/dummy.c:377
__run_hrtimer kernel/time/hrtimer.c:1685 [inline]
__hrtimer_run_queues+0x50b/0xa60 kernel/time/hrtimer.c:1749
hrtimer_run_softirq+0x1b7/0x5d0 kernel/time/hrtimer.c:1766
__do_softirq+0x392/0x7a3 kernel/softirq.c:558
__irq_exit_rcu+0xec/0x170 kernel/softirq.c:637
irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1097
asm_sysvec_apic_timer_interrupt+0x12/0x20
variable_test_bit arch/x86/include/asm/bitops.h:214 [inline]
test_bit include/asm-generic/bitops/instrumented-non-atomic.h:135 [inline]
cpumask_test_cpu include/linux/cpumask.h:344 [inline]
cpu_online include/linux/cpumask.h:895 [inline]
trace_lock_release+0x39/0x150 include/trace/events/lock.h:58
lock_release+0x82/0x810 kernel/locking/lockdep.c:5648
rcu_read_unlock include/linux/rcupdate.h:721 [inline]
__do_sys_getpriority kernel/sys.c:321 [inline]
__se_sys_getpriority+0x6b1/0x9c0 kernel/sys.c:273
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
INITIAL USE at:
lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5637
__raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
_raw_spin_lock_irq+0xcf/0x110 kernel/locking/spinlock.c:170
spin_lock_irq include/linux/spinlock.h:374 [inline]
snd_pcm_group_lock_irq sound/core/pcm_native.c:97 [inline]
snd_pcm_stream_lock_irq sound/core/pcm_native.c:136 [inline]
snd_pcm_hw_params+0xca/0x1740 sound/core/pcm_native.c:686
snd_pcm_oss_change_params_locked+0x244e/0x4460 sound/core/oss/pcm_oss.c:960
snd_pcm_oss_change_params sound/core/oss/pcm_oss.c:1104 [inline]
snd_pcm_oss_make_ready sound/core/oss/pcm_oss.c:1163 [inline]
snd_pcm_oss_sync+0x37c/0xee0 sound/core/oss/pcm_oss.c:1730
snd_pcm_oss_release+0x119/0x270 sound/core/oss/pcm_oss.c:2584
__fput+0x3fc/0x870 fs/file_table.c:280
task_work_run+0x146/0x1c0 kernel/task_work.c:164
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
exit_to_user_mode_prepare+0x209/0x220 kernel/entry/common.c:207
__syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
syscall_exit_to_user_mode+0x2e/0x70 kernel/entry/common.c:300
do_syscall_64+0x53/0xd0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x44/0xae
}
... key at: [<ffffffff91013ac0>] snd_pcm_group_init.__key+0x0/0x40
-> (&timer->lock){....}-{2:2} {
INITIAL USE at:
lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5637
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
snd_timer_resolution sound/core/timer.c:489 [inline]
snd_timer_user_params sound/core/timer.c:1851 [inline]
__snd_timer_user_ioctl+0x1b9d/0x5920 sound/core/timer.c:2100
snd_timer_user_ioctl+0x5d/0x80 sound/core/timer.c:2128
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl+0xfb/0x170 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
}
... key at: [<ffffffff91013080>] snd_timer_new.__key+0x0/0x40
... acquired at:
lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5637
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
snd_timer_notify+0x105/0x3e0 sound/core/timer.c:1086
snd_pcm_timer_notify sound/core/pcm_native.c:595 [inline]
snd_pcm_post_stop sound/core/pcm_native.c:1453 [inline]
snd_pcm_action_single sound/core/pcm_native.c:1229 [inline]
snd_pcm_action sound/core/pcm_native.c:1310 [inline]
snd_pcm_stop+0x3b8/0x4c0 sound/core/pcm_native.c:1476
snd_pcm_drop+0x16d/0x290 sound/core/pcm_native.c:2155
snd_pcm_oss_sync+0x4f4/0xee0 sound/core/oss/pcm_oss.c:1734
snd_pcm_oss_release+0x119/0x270 sound/core/oss/pcm_oss.c:2584
__fput+0x3fc/0x870 fs/file_table.c:280
task_work_run+0x146/0x1c0 kernel/task_work.c:164
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
exit_to_user_mode_prepare+0x209/0x220 kernel/entry/common.c:207
__syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
syscall_exit_to_user_mode+0x2e/0x70 kernel/entry/common.c:300
do_syscall_64+0x53/0xd0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x44/0xae

-> (&new->fa_lock){....}-{2:2} {
INITIAL USE at:
lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5637
__raw_write_lock_irq include/linux/rwlock_api_smp.h:194 [inline]
_raw_write_lock_irq+0xcf/0x110 kernel/locking/spinlock.c:316
fasync_remove_entry+0xff/0x1d0 fs/fcntl.c:891
__fput+0x71e/0x870 fs/file_table.c:277
task_work_run+0x146/0x1c0 kernel/task_work.c:164
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
exit_to_user_mode_prepare+0x209/0x220 kernel/entry/common.c:207
__syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
syscall_exit_to_user_mode+0x2e/0x70 kernel/entry/common.c:300
do_syscall_64+0x53/0xd0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x44/0xae
INITIAL READ USE at:
lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5637
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline]
_raw_read_lock_irqsave+0xd9/0x120 kernel/locking/spinlock.c:236
kill_fasync_rcu fs/fcntl.c:1014 [inline]
kill_fasync+0x13b/0x430 fs/fcntl.c:1035
snd_timer_user_ccallback+0x370/0x540 sound/core/timer.c:1386
snd_timer_notify1+0x1ad/0x350 sound/core/timer.c:516
snd_timer_start1+0x53d/0x640 sound/core/timer.c:578
snd_timer_start sound/core/timer.c:696 [inline]
snd_timer_user_start sound/core/timer.c:1984 [inline]
__snd_timer_user_ioctl+0xb56/0x5920 sound/core/timer.c:2107
snd_timer_user_ioctl+0x5d/0x80 sound/core/timer.c:2128
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl+0xfb/0x170 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
}
... key at: [<ffffffff90c85d40>] fasync_insert_entry.__key+0x0/0x40
... acquired at:
lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5637
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline]
_raw_read_lock_irqsave+0xd9/0x120 kernel/locking/spinlock.c:236
kill_fasync_rcu fs/fcntl.c:1014 [inline]
kill_fasync+0x13b/0x430 fs/fcntl.c:1035
snd_timer_user_ccallback+0x370/0x540 sound/core/timer.c:1386
snd_timer_notify1+0x1ad/0x350 sound/core/timer.c:516
snd_timer_start1+0x53d/0x640 sound/core/timer.c:578
snd_timer_start sound/core/timer.c:696 [inline]
snd_timer_user_start sound/core/timer.c:1984 [inline]
__snd_timer_user_ioctl+0xb56/0x5920 sound/core/timer.c:2107
snd_timer_user_ioctl+0x5d/0x80 sound/core/timer.c:2128
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl+0xfb/0x170 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae

-> (&f->f_owner.lock){...-}-{2:2} {
IN-SOFTIRQ-R at:
lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5637
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline]
_raw_read_lock_irqsave+0xd9/0x120 kernel/locking/spinlock.c:236
send_sigurg+0x25/0x360 fs/fcntl.c:835
sk_send_sigurg+0x6a/0xb0 net/core/sock.c:3172
tcp_check_urg net/ipv4/tcp_input.c:5567 [inline]
tcp_urg+0x2b6/0xb40 net/ipv4/tcp_input.c:5608
tcp_rcv_state_process+0x16b9/0x2410 net/ipv4/tcp_input.c:6575
tcp_v4_do_rcv+0x68c/0xa10 net/ipv4/tcp_ipv4.c:1741
tcp_v4_rcv+0x39db/0x4890 net/ipv4/tcp_ipv4.c:2113
ip_protocol_deliver_rcu+0x1ed/0x3b0 net/ipv4/ip_input.c:204
ip_local_deliver_finish net/ipv4/ip_input.c:231 [inline]
NF_HOOK include/linux/netfilter.h:307 [inline]
ip_local_deliver+0x316/0x490 net/ipv4/ip_input.c:252
__netif_receive_skb_one_core net/core/dev.c:5465 [inline]
__netif_receive_skb+0x1d1/0x500 net/core/dev.c:5579
process_backlog+0x518/0x9a0 net/core/dev.c:6455
__napi_poll+0xbd/0x520 net/core/dev.c:7023
napi_poll net/core/dev.c:7090 [inline]
net_rx_action+0x61c/0xf30 net/core/dev.c:7177
__do_softirq+0x392/0x7a3 kernel/softirq.c:558
run_ksoftirqd+0xc1/0x120 kernel/softirq.c:921
smpboot_thread_fn+0x533/0x9d0 kernel/smpboot.c:164
kthread+0x468/0x490 kernel/kthread.c:327
ret_from_fork+0x1f/0x30
INITIAL USE at:
lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5637
__raw_write_lock_irq include/linux/rwlock_api_smp.h:194 [inline]
_raw_write_lock_irq+0xcf/0x110 kernel/locking/spinlock.c:316
f_modown+0x38/0x340 fs/fcntl.c:91
__f_setown fs/fcntl.c:110 [inline]
f_setown+0x113/0x1a0 fs/fcntl.c:138
do_fcntl+0x1a8/0x1560 fs/fcntl.c:393
__do_sys_fcntl fs/fcntl.c:472 [inline]
__se_sys_fcntl+0xd8/0x1b0 fs/fcntl.c:457
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
INITIAL READ USE at:
lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5637
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline]
_raw_read_lock_irqsave+0xd9/0x120 kernel/locking/spinlock.c:236
send_sigio+0x2f/0x300 fs/fcntl.c:796
kill_fasync_rcu fs/fcntl.c:1021 [inline]
kill_fasync+0x1e4/0x430 fs/fcntl.c:1035
snd_timer_user_ccallback+0x370/0x540 sound/core/timer.c:1386
snd_timer_notify1+0x1ad/0x350 sound/core/timer.c:516
snd_timer_start1+0x53d/0x640 sound/core/timer.c:578
snd_timer_start sound/core/timer.c:696 [inline]
snd_timer_user_start sound/core/timer.c:1984 [inline]
__snd_timer_user_ioctl+0xb56/0x5920 sound/core/timer.c:2107
snd_timer_user_ioctl+0x5d/0x80 sound/core/timer.c:2128
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl+0xfb/0x170 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
}
... key at: [<ffffffff90c84e80>] __alloc_file.__key+0x0/0x10
... acquired at:
lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5637
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline]
_raw_read_lock_irqsave+0xd9/0x120 kernel/locking/spinlock.c:236
send_sigio+0x2f/0x300 fs/fcntl.c:796
kill_fasync_rcu fs/fcntl.c:1021 [inline]
kill_fasync+0x1e4/0x430 fs/fcntl.c:1035
snd_timer_user_ccallback+0x370/0x540 sound/core/timer.c:1386
snd_timer_notify1+0x1ad/0x350 sound/core/timer.c:516
snd_timer_start1+0x53d/0x640 sound/core/timer.c:578
snd_timer_start sound/core/timer.c:696 [inline]
snd_timer_user_start sound/core/timer.c:1984 [inline]
__snd_timer_user_ioctl+0xb56/0x5920 sound/core/timer.c:2107
snd_timer_user_ioctl+0x5d/0x80 sound/core/timer.c:2128
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl+0xfb/0x170 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae

the dependencies between the lock to be acquired
and SOFTIRQ-irq-unsafe lock:
-> (tasklist_lock){.+.+}-{2:2} {
HARDIRQ-ON-R at:
lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5637
__raw_read_lock include/linux/rwlock_api_smp.h:149 [inline]
_raw_read_lock+0x32/0x40 kernel/locking/spinlock.c:228
do_wait+0x224/0x9d0 kernel/exit.c:1511
kernel_wait+0xe4/0x230 kernel/exit.c:1701
call_usermodehelper_exec_sync kernel/umh.c:139 [inline]
call_usermodehelper_exec_work+0xb4/0x220 kernel/umh.c:166
process_one_work+0x853/0x1140 kernel/workqueue.c:2298
worker_thread+0xac1/0x1320 kernel/workqueue.c:2445
kthread+0x468/0x490 kernel/kthread.c:327
ret_from_fork+0x1f/0x30
SOFTIRQ-ON-R at:
lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5637
__raw_read_lock include/linux/rwlock_api_smp.h:149 [inline]
_raw_read_lock+0x32/0x40 kernel/locking/spinlock.c:228
do_wait+0x224/0x9d0 kernel/exit.c:1511
kernel_wait+0xe4/0x230 kernel/exit.c:1701
call_usermodehelper_exec_sync kernel/umh.c:139 [inline]
call_usermodehelper_exec_work+0xb4/0x220 kernel/umh.c:166
process_one_work+0x853/0x1140 kernel/workqueue.c:2298
worker_thread+0xac1/0x1320 kernel/workqueue.c:2445
kthread+0x468/0x490 kernel/kthread.c:327
ret_from_fork+0x1f/0x30
INITIAL USE at:
lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5637
__raw_write_lock_irq include/linux/rwlock_api_smp.h:194 [inline]
_raw_write_lock_irq+0xcf/0x110 kernel/locking/spinlock.c:316
copy_process+0x34bf/0x5ca0 kernel/fork.c:2311
kernel_clone+0x22a/0x7e0 kernel/fork.c:2582
kernel_thread+0x155/0x1d0 kernel/fork.c:2634
rest_init+0x21/0x2e0 init/main.c:690
start_kernel+0x4bf/0x56e init/main.c:1135
secondary_startup_64_no_verify+0xb1/0xbb
INITIAL READ USE at:
lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5637
__raw_read_lock include/linux/rwlock_api_smp.h:149 [inline]
_raw_read_lock+0x32/0x40 kernel/locking/spinlock.c:228
do_wait+0x224/0x9d0 kernel/exit.c:1511
kernel_wait+0xe4/0x230 kernel/exit.c:1701
call_usermodehelper_exec_sync kernel/umh.c:139 [inline]
call_usermodehelper_exec_work+0xb4/0x220 kernel/umh.c:166
process_one_work+0x853/0x1140 kernel/workqueue.c:2298
worker_thread+0xac1/0x1320 kernel/workqueue.c:2445
kthread+0x468/0x490 kernel/kthread.c:327
ret_from_fork+0x1f/0x30
}
... key at: [<ffffffff8c80a058>] tasklist_lock+0x18/0x40
... acquired at:
lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5637
__raw_read_lock include/linux/rwlock_api_smp.h:149 [inline]
_raw_read_lock+0x32/0x40 kernel/locking/spinlock.c:228
send_sigio+0xbe/0x300 fs/fcntl.c:810
dnotify_handle_event+0x136/0x450 fs/notify/dnotify/dnotify.c:97
fsnotify_handle_event fs/notify/fsnotify.c:313 [inline]
send_to_group+0x9a1/0xdd0 fs/notify/fsnotify.c:367
fsnotify+0xa65/0x1370 fs/notify/fsnotify.c:543
fsnotify_name include/linux/fsnotify.h:36 [inline]
fsnotify_dirent include/linux/fsnotify.h:42 [inline]
fsnotify_create include/linux/fsnotify.h:204 [inline]
open_last_lookups fs/namei.c:3352 [inline]
path_openat+0x1598/0x3660 fs/namei.c:3556
do_filp_open+0x277/0x4f0 fs/namei.c:3586
do_sys_openat2+0x13b/0x500 fs/open.c:1212
do_sys_open fs/open.c:1228 [inline]
__do_sys_creat fs/open.c:1304 [inline]
__se_sys_creat fs/open.c:1298 [inline]
__x64_sys_creat+0x11f/0x160 fs/open.c:1298
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae

stack backtrace:
CPU: 1 PID: 12930 Comm: syz-executor.2 Not tainted 5.16.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1dc/0x2d8 lib/dump_stack.c:106
print_bad_irq_dependency kernel/locking/lockdep.c:2577 [inline]
check_irq_usage kernel/locking/lockdep.c:2816 [inline]
check_prev_add kernel/locking/lockdep.c:3067 [inline]
check_prevs_add kernel/locking/lockdep.c:3186 [inline]
validate_chain+0x6f4c/0x8240 kernel/locking/lockdep.c:3801
__lock_acquire+0x1382/0x2b00 kernel/locking/lockdep.c:5027
lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5637
__raw_read_lock include/linux/rwlock_api_smp.h:149 [inline]
_raw_read_lock+0x32/0x40 kernel/locking/spinlock.c:228
send_sigio+0xbe/0x300 fs/fcntl.c:810
dnotify_handle_event+0x136/0x450 fs/notify/dnotify/dnotify.c:97
fsnotify_handle_event fs/notify/fsnotify.c:313 [inline]
send_to_group+0x9a1/0xdd0 fs/notify/fsnotify.c:367
fsnotify+0xa65/0x1370 fs/notify/fsnotify.c:543
fsnotify_name include/linux/fsnotify.h:36 [inline]
fsnotify_dirent include/linux/fsnotify.h:42 [inline]
fsnotify_create include/linux/fsnotify.h:204 [inline]
open_last_lookups fs/namei.c:3352 [inline]
path_openat+0x1598/0x3660 fs/namei.c:3556
do_filp_open+0x277/0x4f0 fs/namei.c:3586
do_sys_openat2+0x13b/0x500 fs/open.c:1212
do_sys_open fs/open.c:1228 [inline]
__do_sys_creat fs/open.c:1304 [inline]
__se_sys_creat fs/open.c:1298 [inline]
__x64_sys_creat+0x11f/0x160 fs/open.c:1298
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fbb4226fe99
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fbb40be5168 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00007fbb42382f60 RCX: 00007fbb4226fe99
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000000
RBP: 00007fbb422c9ff1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd3f2a44cf R14: 00007fbb40be5300 R15: 0000000000022000
</TASK>

---
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