============================================ WARNING: possible recursive locking detected 5.11.0-syzkaller #0 Not tainted -------------------------------------------- systemd-udevd/4804 is trying to acquire lock: ffff888071ffb130 (&runtime->sleep){..-.}-{2:2}, at: spin_lock include/linux/spinlock.h:354 [inline] ffff888071ffb130 (&runtime->sleep){..-.}-{2:2}, at: io_poll_double_wake+0x269/0x550 fs/io_uring.c:4960 but task is already holding lock: ffff888071ff8130 (&runtime->sleep){..-.}-{2:2}, at: __wake_up_common_lock kernel/sched/wait.c:137 [inline] ffff888071ff8130 (&runtime->sleep){..-.}-{2:2}, at: __wake_up+0xb8/0x140 kernel/sched/wait.c:157 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 2 locks held by systemd-udevd/4804: #0: ffff888147281908 (&group->lock){..-.}-{2:2}, at: snd_pcm_period_elapsed+0x2c/0x210 sound/core/pcm_lib.c:1799 #1: ffff888071ff8130 (&runtime->sleep){..-.}-{2:2}, at: __wake_up_common_lock kernel/sched/wait.c:137 [inline] #1: ffff888071ff8130 (&runtime->sleep){..-.}-{2:2}, at: __wake_up+0xb8/0x140 kernel/sched/wait.c:157 stack backtrace: CPU: 0 PID: 4804 Comm: systemd-udevd Not tainted 5.11.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x125/0x19e lib/dump_stack.c:120 __lock_acquire+0x2303/0x5e60 kernel/locking/lockdep.c:4738 lock_acquire+0x114/0x5f0 kernel/locking/lockdep.c:5510 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:354 [inline] io_poll_double_wake+0x269/0x550 fs/io_uring.c:4960 __wake_up_common+0x2aa/0x4e0 kernel/sched/wait.c:108 __wake_up_common_lock kernel/sched/wait.c:138 [inline] __wake_up+0xd4/0x140 kernel/sched/wait.c:157 snd_pcm_update_state+0x3e9/0x440 sound/core/pcm_lib.c:203 snd_pcm_update_hw_ptr0+0x1005/0x1910 sound/core/pcm_lib.c:464 snd_pcm_period_elapsed+0xfb/0x210 sound/core/pcm_lib.c:1805 dummy_hrtimer_callback+0x87/0x190 sound/drivers/dummy.c:378 __run_hrtimer kernel/time/hrtimer.c:1519 [inline] __hrtimer_run_queues+0x4c9/0xa00 kernel/time/hrtimer.c:1583 hrtimer_run_softirq+0x176/0x1e0 kernel/time/hrtimer.c:1600 __do_softirq+0x318/0x714 kernel/softirq.c:345 invoke_softirq kernel/softirq.c:221 [inline] __irq_exit_rcu+0x1d8/0x200 kernel/softirq.c:422 irq_exit_rcu+0x5/0x20 kernel/softirq.c:434 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1100 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:632 RIP: 0010:debug_lockdep_rcu_enabled+0x12/0x30 kernel/rcu/update.c:280 Code: 48 71 b2 76 00 00 00 f0 c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 31 c0 83 3d 37 a2 65 04 00 74 1e 83 3d d2 d1 65 04 00 <74> 15 65 48 8b 0c 25 80 ef 01 00 31 c0 83 b9 8c 09 00 00 00 0f 94 RSP: 0018:ffffc900015efa10 EFLAGS: 00000202 RAX: 0000000000000000 RBX: ffff888020c80d3c RCX: ffff888012b88000 RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 00000000fffffffe RBP: 0000000000000000 R08: ffffffff81749da0 R09: fffffbfff1b6ad1e R10: fffffbfff1b6ad1e R11: 0000000000000000 R12: 00000000000041ed R13: 1ffff110041901a7 R14: ffff888020c80d38 R15: dffffc0000000000 acl_permission_check fs/namei.c:331 [inline] generic_permission+0x6c/0x5b0 fs/namei.c:392 do_inode_permission fs/namei.c:453 [inline] inode_permission+0xa4/0x500 fs/namei.c:513 may_lookup fs/namei.c:1656 [inline] link_path_walk+0x27a/0xcb0 fs/namei.c:2208 path_openat+0x1ee/0x3860 fs/namei.c:3494 do_filp_open+0x191/0x3a0 fs/namei.c:3525 do_sys_openat2+0xba/0x380 fs/open.c:1187 do_sys_open fs/open.c:1203 [inline] __do_sys_open fs/open.c:1211 [inline] __se_sys_open fs/open.c:1207 [inline] __x64_sys_open+0x1af/0x1e0 fs/open.c:1207 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fbf6895e9b1 Code: f7 d8 bf ff ff ff ff 64 89 02 eb cb 0f 1f 00 66 2e 0f 1f 84 00 00 00 00 00 80 3f 00 74 1b be 00 08 09 00 b8 02 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 1f 89 c7 e9 00 ff ff ff 48 8b 05 b1 54 2e 00 RSP: 002b:00007ffecd345d38 EFLAGS: 00000202 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00005604d1ec1700 RCX: 00007fbf6895e9b1 RDX: 00000000000000fd RSI: 0000000000090800 RDI: 00005604d1e9fb70 RBP: 00007fbf69b14710 R08: 00005604d1e8e260 R09: 0000000000001010 R10: 00000000000029f0 R11: 0000000000000202 R12: 0000000000000000 R13: 00005604d1e9fb70 R14: 00000000000000fd R15: 00005604d1e9fb70