======================================================== WARNING: possible irq lock inversion dependency detected 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Not tainted -------------------------------------------------------- syz-executor.2/5841 just changed the state of lock: ffff888029ca8148 (&timer->lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] ffff888029ca8148 (&timer->lock){+.+.}-{2:2}, at: class_spinlock_constructor include/linux/spinlock.h:561 [inline] ffff888029ca8148 (&timer->lock){+.+.}-{2:2}, at: snd_timer_close_locked+0x53/0x8d0 sound/core/timer.c:412 but this lock was taken by another, SOFTIRQ-safe lock in the past: (&group->lock#2){..-.}-{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 *** 2 locks held by syz-executor.2/5841: #0: ffff888023b1f568 (&tu->ioctl_lock){+.+.}-{3:3}, at: class_mutex_constructor include/linux/mutex.h:169 [inline] #0: ffff888023b1f568 (&tu->ioctl_lock){+.+.}-{3:3}, at: snd_timer_user_ioctl_compat+0xd3/0xc20 sound/core/timer_compat.c:119 #1: ffffffff8f2d3f68 (register_mutex){+.+.}-{3:3}, at: class_mutex_constructor include/linux/mutex.h:169 [inline] #1: ffffffff8f2d3f68 (register_mutex){+.+.}-{3:3}, at: snd_timer_close sound/core/timer.c:463 [inline] #1: ffffffff8f2d3f68 (register_mutex){+.+.}-{3:3}, at: snd_timer_user_tselect sound/core/timer.c:1694 [inline] #1: ffffffff8f2d3f68 (register_mutex){+.+.}-{3:3}, at: __snd_timer_user_ioctl+0x72d/0x5370 sound/core/timer.c:2027 the shortest dependencies between 2nd lock and 1st lock: -> (&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_cmp8+0x8/0x90 kernel/kcov.c:284 on_stack arch/x86/include/asm/stacktrace.h:60 [inline] unwind_next_frame+0x1df5/0x2a00 arch/x86/kernel/unwind_orc.c:665 arch_stack_walk+0x151/0x1b0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:312 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3798 [inline] slab_alloc_node mm/slub.c:3845 [inline] kmem_cache_alloc+0x174/0x340 mm/slub.c:3852 kmem_cache_zalloc include/linux/slab.h:739 [inline] fill_pool lib/debugobjects.c:168 [inline] debug_objects_fill_pool+0x46e/0x9b0 lib/debugobjects.c:615 debug_object_activate+0x135/0x510 lib/debugobjects.c:704 debug_rcu_head_queue kernel/rcu/rcu.h:227 [inline] __call_rcu_common kernel/rcu/tree.c:2719 [inline] call_rcu+0x97/0xa70 kernel/rcu/tree.c:2838 context_switch kernel/sched/core.c:5412 [inline] __schedule+0x17db/0x4a20 kernel/sched/core.c:6736 __schedule_loop kernel/sched/core.c:6813 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6828 futex_wait_queue+0x14e/0x1d0 kernel/futex/waitwake.c:370 __futex_wait+0x17f/0x320 kernel/futex/waitwake.c:669 futex_wait+0x101/0x360 kernel/futex/waitwake.c:697 do_futex+0x33b/0x560 kernel/futex/syscalls.c:102 __do_sys_futex_time32 kernel/futex/syscalls.c:509 [inline] __se_sys_futex_time32+0x3dd/0x460 kernel/futex/syscalls.c:492 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbe/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7a/0x84 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 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __ia32_sys_close+0x7f/0x110 fs/open.c:1541 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbe/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7a/0x84 } ... key at: [] snd_pcm_group_init.__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 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __ia32_sys_close+0x7f/0x110 fs/open.c:1541 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbe/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7a/0x84 -> (&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 sound/core/timer.c:464 [inline] snd_timer_user_tselect sound/core/timer.c:1694 [inline] __snd_timer_user_ioctl+0x738/0x5370 sound/core/timer.c:2027 __snd_timer_user_ioctl_compat sound/core/timer_compat.c:101 [inline] snd_timer_user_ioctl_compat+0x426/0xc20 sound/core/timer_compat.c:120 __do_compat_sys_ioctl fs/ioctl.c:1004 [inline] __se_compat_sys_ioctl+0x51c/0xca0 fs/ioctl.c:947 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbe/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7a/0x84 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 sound/core/timer.c:464 [inline] snd_timer_user_tselect sound/core/timer.c:1694 [inline] __snd_timer_user_ioctl+0x738/0x5370 sound/core/timer.c:2027 __snd_timer_user_ioctl_compat sound/core/timer_compat.c:101 [inline] snd_timer_user_ioctl_compat+0x426/0xc20 sound/core/timer_compat.c:120 __do_compat_sys_ioctl fs/ioctl.c:1004 [inline] __se_compat_sys_ioctl+0x51c/0xca0 fs/ioctl.c:947 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbe/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7a/0x84 INITIAL USE 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 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __ia32_sys_close+0x7f/0x110 fs/open.c:1541 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbe/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7a/0x84 } ... key at: [] snd_timer_new.__key+0x0/0x20 ... acquired at: mark_lock+0x223/0x350 kernel/locking/lockdep.c:4678 __lock_acquire+0x116e/0x1fd0 kernel/locking/lockdep.c:5091 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 sound/core/timer.c:464 [inline] snd_timer_user_tselect sound/core/timer.c:1694 [inline] __snd_timer_user_ioctl+0x738/0x5370 sound/core/timer.c:2027 __snd_timer_user_ioctl_compat sound/core/timer_compat.c:101 [inline] snd_timer_user_ioctl_compat+0x426/0xc20 sound/core/timer_compat.c:120 __do_compat_sys_ioctl fs/ioctl.c:1004 [inline] __se_compat_sys_ioctl+0x51c/0xca0 fs/ioctl.c:947 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbe/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7a/0x84 stack backtrace: CPU: 1 PID: 5841 Comm: syz-executor.2 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+0x867/0xc20 kernel/locking/lockdep.c:4236 mark_lock+0x223/0x350 kernel/locking/lockdep.c:4678 __lock_acquire+0x116e/0x1fd0 kernel/locking/lockdep.c:5091 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 sound/core/timer.c:464 [inline] snd_timer_user_tselect sound/core/timer.c:1694 [inline] __snd_timer_user_ioctl+0x738/0x5370 sound/core/timer.c:2027 __snd_timer_user_ioctl_compat sound/core/timer_compat.c:101 [inline] snd_timer_user_ioctl_compat+0x426/0xc20 sound/core/timer_compat.c:120 __do_compat_sys_ioctl fs/ioctl.c:1004 [inline] __se_compat_sys_ioctl+0x51c/0xca0 fs/ioctl.c:947 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbe/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7a/0x84 RIP: 0023:0xf72ba579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000f5e6a5ac EFLAGS: 00000206 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000040345410 RDX: 0000000020000140 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 ret 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 90 nop 31: 90 nop 32: 90 nop 33: 90 nop 34: 90 nop 35: 90 nop 36: 90 nop 37: 90 nop 38: 90 nop 39: 90 nop 3a: 90 nop 3b: 90 nop 3c: 90 nop 3d: 90 nop