============================================ WARNING: possible recursive locking detected 5.16.0-rc7-syzkaller #0 Not tainted -------------------------------------------- udevd/2972 is trying to acquire lock: ffff88805c08c130 (&runtime->sleep){..-.}-{2:2}, at: io_poll_double_wake+0x2ba/0x7c0 fs/io_uring.c:5467 but task is already holding lock: ffff88805bf76130 (&runtime->sleep){..-.}-{2:2}, at: __wake_up_common_lock+0xb4/0x130 kernel/sched/wait.c:137 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&runtime->sleep); lock(&runtime->sleep); *** DEADLOCK *** May be due to missing lock nesting notation 3 locks held by udevd/2972: #0: ffffc90001b17cb8 ((&dpcm->timer)){+.-.}-{0:0}, at: lockdep_copy_map include/linux/lockdep.h:35 [inline] #0: ffffc90001b17cb8 ((&dpcm->timer)){+.-.}-{0:0}, at: call_timer_fn+0xd5/0x6b0 kernel/time/timer.c:1411 #1: ffff888024721110 (&group->lock){..-.}-{2:2}, at: _snd_pcm_stream_lock_irqsave+0x9f/0xd0 sound/core/pcm_native.c:170 #2: ffff88805bf76130 (&runtime->sleep){..-.}-{2:2}, at: __wake_up_common_lock+0xb4/0x130 kernel/sched/wait.c:137 stack backtrace: CPU: 0 PID: 2972 Comm: udevd Not tainted 5.16.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2956 [inline] check_deadlock kernel/locking/lockdep.c:2999 [inline] validate_chain kernel/locking/lockdep.c:3788 [inline] __lock_acquire.cold+0x149/0x3ab kernel/locking/lockdep.c:5027 lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162 io_poll_double_wake+0x2ba/0x7c0 fs/io_uring.c:5467 __wake_up_common+0x147/0x650 kernel/sched/wait.c:108 __wake_up_common_lock+0xd0/0x130 kernel/sched/wait.c:138 snd_pcm_update_state+0x46a/0x540 sound/core/pcm_lib.c:204 snd_pcm_update_hw_ptr0+0xa75/0x1a50 sound/core/pcm_lib.c:465 snd_pcm_period_elapsed_under_stream_lock+0x15a/0x230 sound/core/pcm_lib.c:1817 snd_pcm_period_elapsed+0x28/0x50 sound/core/pcm_lib.c:1849 loopback_jiffies_timer_function+0x1c4/0x240 sound/drivers/aloop.c:668 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x67c/0xa30 kernel/time/timer.c:1734 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x45/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0033:0x7fb1ceb901da Code: 48 89 f2 b9 00 01 00 00 48 89 fe bf 9c ff ff ff e9 0b 00 00 00 66 2e 0f 1f 84 00 00 00 00 00 90 41 89 ca b8 06 01 00 00 0f 05 <3d> 00 f0 ff ff 77 07 31 c0 c3 0f 1f 40 00 48 8b 15 69 fc 0c 00 f7 RSP: 002b:00007fff5dea3088 EFLAGS: 00000202 RAX: 0000000000000000 RBX: 0000560606685b10 RCX: 00007fb1ceb901da RDX: 00007fff5dea3090 RSI: 00007fb1cec2675a RDI: 000000000000000d RBP: 000000000000000d R08: 0000000000090800 R09: 000056060669edf0 R10: 0000000000001000 R11: 0000000000000202 R12: 00007fff5dea3090 R13: 00000000000000ff R14: 00007fff5dea3180 R15: 0000000000000000 usblp0: nonzero read bulk status received: -71