======================================================== WARNING: possible irq lock inversion dependency detected 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Not tainted -------------------------------------------------------- udevd/6211 just changed the state of lock: ffff888029bc9910 (&group->lock#2){..-.}-{2:2}, at: class_pcm_stream_lock_irqsave_constructor include/sound/pcm.h:669 [inline] ffff888029bc9910 (&group->lock#2){..-.}-{2:2}, at: snd_pcm_period_elapsed+0x21/0x50 sound/core/pcm_lib.c:1904 but this lock took another, SOFTIRQ-unsafe lock in the past: (&timer->lock){+.+.}-{2:2} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&timer->lock); local_irq_disable(); lock(&group->lock#2); lock(&timer->lock); lock(&group->lock#2); *** DEADLOCK *** 1 lock held by udevd/6211: #0: ffff8880162e5778 (&kernfs_locks->open_file_mutex[count]){+.+.}-{3:3}, at: kernfs_open_file_mutex_lock fs/kernfs/file.c:56 [inline] #0: ffff8880162e5778 (&kernfs_locks->open_file_mutex[count]){+.+.}-{3:3}, at: kernfs_unlink_open_file+0x73/0x510 fs/kernfs/file.c:563 the shortest dependencies between 2nd lock and 1st lock: -> (&timer->lock){+.+.}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] class_spinlock_constructor include/linux/spinlock.h:561 [inline] snd_timer_close_locked+0x53/0x8d0 sound/core/timer.c:412 snd_timer_close+0xae/0x130 sound/core/timer.c:464 snd_seq_timer_close+0xa9/0xe0 sound/core/seq/seq_timer.c:302 queue_delete sound/core/seq/seq_queue.c:126 [inline] snd_seq_queue_delete+0x8f/0xf0 sound/core/seq/seq_queue.c:188 delete_seq_queue sound/core/seq/oss/seq_oss_init.c:371 [inline] snd_seq_oss_release+0x1d3/0x310 sound/core/seq/oss/seq_oss_init.c:416 odev_release+0x56/0x80 sound/core/seq/oss/seq_oss.c:144 __fput+0x429/0x8a0 fs/file_table.c:422 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __x64_sys_close+0x7f/0x110 fs/open.c:1541 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 SOFTIRQ-ON-W at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] class_spinlock_constructor include/linux/spinlock.h:561 [inline] snd_timer_close_locked+0x53/0x8d0 sound/core/timer.c:412 snd_timer_close+0xae/0x130 sound/core/timer.c:464 snd_seq_timer_close+0xa9/0xe0 sound/core/seq/seq_timer.c:302 queue_delete sound/core/seq/seq_queue.c:126 [inline] snd_seq_queue_delete+0x8f/0xf0 sound/core/seq/seq_queue.c:188 delete_seq_queue sound/core/seq/oss/seq_oss_init.c:371 [inline] snd_seq_oss_release+0x1d3/0x310 sound/core/seq/oss/seq_oss_init.c:416 odev_release+0x56/0x80 sound/core/seq/oss/seq_oss.c:144 __fput+0x429/0x8a0 fs/file_table.c:422 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __x64_sys_close+0x7f/0x110 fs/open.c:1541 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 INITIAL USE at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] class_spinlock_constructor include/linux/spinlock.h:561 [inline] snd_timer_close_locked+0x53/0x8d0 sound/core/timer.c:412 snd_timer_close+0xae/0x130 sound/core/timer.c:464 snd_seq_timer_close+0xa9/0xe0 sound/core/seq/seq_timer.c:302 queue_delete sound/core/seq/seq_queue.c:126 [inline] snd_seq_queue_delete+0x8f/0xf0 sound/core/seq/seq_queue.c:188 delete_seq_queue sound/core/seq/oss/seq_oss_init.c:371 [inline] snd_seq_oss_release+0x1d3/0x310 sound/core/seq/oss/seq_oss_init.c:416 odev_release+0x56/0x80 sound/core/seq/oss/seq_oss.c:144 __fput+0x429/0x8a0 fs/file_table.c:422 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __x64_sys_close+0x7f/0x110 fs/open.c:1541 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 } ... key at: [] snd_timer_new.__key+0x0/0x20 ... acquired at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:574 [inline] snd_timer_notify+0x103/0x3d0 sound/core/timer.c:1040 snd_pcm_timer_notify sound/core/pcm_native.c:622 [inline] snd_pcm_post_stop sound/core/pcm_native.c:1520 [inline] snd_pcm_action sound/core/pcm_native.c:1370 [inline] snd_pcm_stop+0x358/0x490 sound/core/pcm_native.c:1543 snd_pcm_drop+0x158/0x250 sound/core/pcm_native.c:2208 snd_pcm_oss_sync+0x202/0xc30 sound/core/oss/pcm_oss.c:1734 snd_pcm_oss_release+0x11e/0x280 sound/core/oss/pcm_oss.c:2575 __fput+0x429/0x8a0 fs/file_table.c:422 task_work_run+0x24f/0x310 kernel/task_work.c:180 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:108 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:201 [inline] syscall_exit_to_user_mode+0x168/0x360 kernel/entry/common.c:212 do_syscall_64+0x10a/0x240 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x6d/0x75 -> (&group->lock#2){..-.}-{2:2} { IN-SOFTIRQ-W at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 class_pcm_stream_lock_irqsave_constructor include/sound/pcm.h:669 [inline] snd_pcm_period_elapsed+0x21/0x50 sound/core/pcm_lib.c:1904 dummy_hrtimer_callback+0x7f/0x180 sound/drivers/dummy.c:385 __run_hrtimer kernel/time/hrtimer.c:1692 [inline] __hrtimer_run_queues+0x595/0xd00 kernel/time/hrtimer.c:1756 hrtimer_run_softirq+0x19a/0x2c0 kernel/time/hrtimer.c:1773 __do_softirq+0x2bc/0x943 kernel/softirq.c:554 invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf2/0x1c0 kernel/softirq.c:633 irq_exit_rcu+0x9/0x30 kernel/softirq.c:645 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 __sanitizer_cov_trace_cmp4+0x8/0x90 kernel/kcov.c:278 unwind_next_frame+0x1d7b/0x2a00 arch/x86/kernel/unwind_orc.c:664 arch_stack_walk+0x151/0x1b0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47 __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:541 kvfree_call_rcu+0xfc/0x790 kernel/rcu/tree.c:3443 kernfs_unlink_open_file+0x42d/0x510 fs/kernfs/file.c:584 kernfs_fop_release+0x128/0x190 fs/kernfs/file.c:756 __fput+0x429/0x8a0 fs/file_table.c:422 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __x64_sys_close+0x7f/0x110 fs/open.c:1541 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 INITIAL USE at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0xd3/0x120 kernel/locking/spinlock.c:170 spin_lock_irq include/linux/spinlock.h:376 [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] class_pcm_stream_lock_irq_constructor include/sound/pcm.h:666 [inline] snd_pcm_hw_params+0x201/0x1ea0 sound/core/pcm_native.c:740 snd_pcm_oss_change_params_locked+0x20d5/0x3e00 sound/core/oss/pcm_oss.c:965 snd_pcm_oss_change_params sound/core/oss/pcm_oss.c:1105 [inline] snd_pcm_oss_make_ready+0x11d/0x350 sound/core/oss/pcm_oss.c:1164 snd_pcm_oss_sync+0x1bd/0xc30 sound/core/oss/pcm_oss.c:1730 snd_pcm_oss_release+0x11e/0x280 sound/core/oss/pcm_oss.c:2575 __fput+0x429/0x8a0 fs/file_table.c:422 task_work_run+0x24f/0x310 kernel/task_work.c:180 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:108 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:201 [inline] syscall_exit_to_user_mode+0x168/0x360 kernel/entry/common.c:212 do_syscall_64+0x10a/0x240 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x6d/0x75 } ... key at: [] snd_pcm_group_init.__key+0x0/0x20 ... acquired at: mark_lock+0x223/0x350 kernel/locking/lockdep.c:4678 __lock_acquire+0xbcd/0x1fd0 kernel/locking/lockdep.c:5091 lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 class_pcm_stream_lock_irqsave_constructor include/sound/pcm.h:669 [inline] snd_pcm_period_elapsed+0x21/0x50 sound/core/pcm_lib.c:1904 dummy_hrtimer_callback+0x7f/0x180 sound/drivers/dummy.c:385 __run_hrtimer kernel/time/hrtimer.c:1692 [inline] __hrtimer_run_queues+0x595/0xd00 kernel/time/hrtimer.c:1756 hrtimer_run_softirq+0x19a/0x2c0 kernel/time/hrtimer.c:1773 __do_softirq+0x2bc/0x943 kernel/softirq.c:554 invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf2/0x1c0 kernel/softirq.c:633 irq_exit_rcu+0x9/0x30 kernel/softirq.c:645 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 __sanitizer_cov_trace_cmp4+0x8/0x90 kernel/kcov.c:278 unwind_next_frame+0x1d7b/0x2a00 arch/x86/kernel/unwind_orc.c:664 arch_stack_walk+0x151/0x1b0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47 __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:541 kvfree_call_rcu+0xfc/0x790 kernel/rcu/tree.c:3443 kernfs_unlink_open_file+0x42d/0x510 fs/kernfs/file.c:584 kernfs_fop_release+0x128/0x190 fs/kernfs/file.c:756 __fput+0x429/0x8a0 fs/file_table.c:422 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __x64_sys_close+0x7f/0x110 fs/open.c:1541 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 stack backtrace: CPU: 1 PID: 6211 Comm: udevd Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 mark_lock_irq+0x80c/0xc20 kernel/locking/lockdep.c:4243 mark_lock+0x223/0x350 kernel/locking/lockdep.c:4678 __lock_acquire+0xbcd/0x1fd0 kernel/locking/lockdep.c:5091 lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 class_pcm_stream_lock_irqsave_constructor include/sound/pcm.h:669 [inline] snd_pcm_period_elapsed+0x21/0x50 sound/core/pcm_lib.c:1904 dummy_hrtimer_callback+0x7f/0x180 sound/drivers/dummy.c:385 __run_hrtimer kernel/time/hrtimer.c:1692 [inline] __hrtimer_run_queues+0x595/0xd00 kernel/time/hrtimer.c:1756 hrtimer_run_softirq+0x19a/0x2c0 kernel/time/hrtimer.c:1773 __do_softirq+0x2bc/0x943 kernel/softirq.c:554 invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf2/0x1c0 kernel/softirq.c:633 irq_exit_rcu+0x9/0x30 kernel/softirq.c:645 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:get_current arch/x86/include/asm/current.h:49 [inline] RIP: 0010:write_comp_data kernel/kcov.c:235 [inline] RIP: 0010:__sanitizer_cov_trace_cmp4+0x8/0x90 kernel/kcov.c:278 Code: 44 0a 20 c3 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 4c 8b 04 24 <65> 48 8b 14 25 40 d0 03 00 65 8b 05 20 da 6e 7e a9 00 01 ff 00 74 RSP: 0018:ffffc900032b7820 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffff8880228b0000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001 RBP: ffffc900032b7900 R08: ffffffff8140aceb R09: ffffffff8140a8df R10: 0000000000000003 R11: ffff8880228b0000 R12: ffffc900032b7cd8 R13: dffffc0000000000 R14: 0000000000000001 R15: 1ffff92000656f20 unwind_next_frame+0x1d7b/0x2a00 arch/x86/kernel/unwind_orc.c:664 arch_stack_walk+0x151/0x1b0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47 __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:541 kvfree_call_rcu+0xfc/0x790 kernel/rcu/tree.c:3443 kernfs_unlink_open_file+0x42d/0x510 fs/kernfs/file.c:584 kernfs_fop_release+0x128/0x190 fs/kernfs/file.c:756 __fput+0x429/0x8a0 fs/file_table.c:422 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __x64_sys_close+0x7f/0x110 fs/open.c:1541 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 RIP: 0033:0x7f64a971a37f Code: af 6a 0d 00 f7 d8 64 89 02 48 83 c8 ff 44 89 c7 48 89 04 24 e8 e1 fc f9 ff 48 8b 04 24 48 83 c4 28 c3 c3 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 10 48 8b 15 7a 6a 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffea3941b48 EFLAGS: 00000202 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 000055bbaf641640 RCX: 00007f64a971a37f RDX: 00007f64a97ed860 RSI: 0000000000000000 RDI: 0000000000000008 RBP: 0000000000000000 R08: 0000000000000008 R09: 0000000000000000 R10: 0000000000000010 R11: 0000000000000202 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 000055bb898e9fc1 ---------------- Code disassembly (best guess): 0: 44 0a 20 or (%rax),%r12b 3: c3 ret 4: cc int3 5: cc int3 6: cc int3 7: cc int3 8: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) f: 00 00 00 12: 90 nop 13: 90 nop 14: 90 nop 15: 90 nop 16: 90 nop 17: 90 nop 18: 90 nop 19: 90 nop 1a: 90 nop 1b: 90 nop 1c: 90 nop 1d: 90 nop 1e: 90 nop 1f: 90 nop 20: 90 nop 21: 90 nop 22: f3 0f 1e fa endbr64 26: 4c 8b 04 24 mov (%rsp),%r8 * 2a: 65 48 8b 14 25 40 d0 mov %gs:0x3d040,%rdx <-- trapping instruction 31: 03 00 33: 65 8b 05 20 da 6e 7e mov %gs:0x7e6eda20(%rip),%eax # 0x7e6eda5a 3a: a9 00 01 ff 00 test $0xff0100,%eax 3f: 74 .byte 0x74