======================================================== WARNING: possible irq lock inversion dependency detected 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Not tainted -------------------------------------------------------- syz-executor.4/5821 just changed the state of lock: ffff888029ff9110 (&group->lock#2){..-.}-{2:2}, at: _snd_pcm_stream_lock_irqsave+0xa0/0xd0 sound/core/pcm_native.c:170 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 *** no locks held by syz-executor.4/5821. the shortest dependencies between 2nd lock and 1st lock: -> (&timer->lock){+.+.}-{2:2} { HARDIRQ-ON-W at: lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719 __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+0x65/0xbd0 sound/core/timer.c:412 snd_timer_close+0x8b/0xf0 sound/core/timer.c:464 snd_timer_user_release+0x91/0x260 sound/core/timer.c:1468 __fput+0x270/0xb80 fs/file_table.c:422 __fput_sync+0x47/0x50 fs/file_table.c:507 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __x64_sys_close+0x86/0x100 fs/open.c:1541 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 SOFTIRQ-ON-W at: lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719 __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+0x65/0xbd0 sound/core/timer.c:412 snd_timer_close+0x8b/0xf0 sound/core/timer.c:464 snd_timer_user_release+0x91/0x260 sound/core/timer.c:1468 __fput+0x270/0xb80 fs/file_table.c:422 __fput_sync+0x47/0x50 fs/file_table.c:507 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __x64_sys_close+0x86/0x100 fs/open.c:1541 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:574 [inline] snd_timer_notify+0x111/0x3e0 sound/core/timer.c:1040 snd_pcm_timer_notify sound/core/pcm_native.c:622 [inline] snd_pcm_post_start+0x272/0x350 sound/core/pcm_native.c:1459 snd_pcm_action_single+0x10a/0x150 sound/core/pcm_native.c:1289 snd_pcm_action+0x70/0x90 sound/core/pcm_native.c:1370 __snd_pcm_lib_xfer+0x13f5/0x1ea0 sound/core/pcm_lib.c:2371 snd_pcm_lib_write include/sound/pcm.h:1166 [inline] snd_pcm_write+0x184/0x260 sound/core/pcm_native.c:3497 vfs_write+0x298/0x1100 fs/read_write.c:588 ksys_write+0x12f/0x260 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 } ... key at: [] __key.6+0x0/0x40 ... acquired at: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:574 [inline] snd_timer_notify+0x111/0x3e0 sound/core/timer.c:1040 snd_pcm_timer_notify sound/core/pcm_native.c:622 [inline] snd_pcm_post_start+0x272/0x350 sound/core/pcm_native.c:1459 snd_pcm_action_single+0x10a/0x150 sound/core/pcm_native.c:1289 snd_pcm_action+0x70/0x90 sound/core/pcm_native.c:1370 __snd_pcm_lib_xfer+0x13f5/0x1ea0 sound/core/pcm_lib.c:2371 snd_pcm_lib_write include/sound/pcm.h:1166 [inline] snd_pcm_write+0x184/0x260 sound/core/pcm_native.c:3497 vfs_write+0x298/0x1100 fs/read_write.c:588 ksys_write+0x12f/0x260 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 -> (&group->lock#2){..-.}-{2:2} { IN-SOFTIRQ-W at: lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 _snd_pcm_stream_lock_irqsave+0xa0/0xd0 sound/core/pcm_native.c:170 class_pcm_stream_lock_irqsave_constructor include/sound/pcm.h:669 [inline] snd_pcm_period_elapsed+0x20/0x50 sound/core/pcm_lib.c:1904 dummy_hrtimer_callback+0x9d/0x1c0 sound/drivers/dummy.c:385 __run_hrtimer kernel/time/hrtimer.c:1692 [inline] __hrtimer_run_queues+0x20c/0xc20 kernel/time/hrtimer.c:1756 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1773 __do_softirq+0x218/0x8de kernel/softirq.c:554 invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu kernel/softirq.c:633 [inline] irq_exit_rcu+0xb9/0x120 kernel/softirq.c:645 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 check_kcov_mode kernel/kcov.c:173 [inline] __sanitizer_cov_trace_pc+0x18/0x60 kernel/kcov.c:207 __orc_find+0x63/0x130 arch/x86/kernel/unwind_orc.c:104 orc_find arch/x86/kernel/unwind_orc.c:227 [inline] unwind_next_frame+0x335/0x23a0 arch/x86/kernel/unwind_orc.c:494 arch_stack_walk+0x100/0x170 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122 __kfence_alloc+0x1bf/0x15d0 mm/kfence/core.c:1095 kfence_alloc include/linux/kfence.h:129 [inline] slab_alloc_node mm/slub.c:3831 [inline] kmem_cache_alloc+0x1de/0x320 mm/slub.c:3852 getname_flags.part.0+0x50/0x4f0 fs/namei.c:139 getname_flags+0x9b/0xf0 include/linux/audit.h:322 user_path_at_empty+0x2c/0x60 fs/namei.c:2920 user_path_at include/linux/namei.h:57 [inline] ksys_umount fs/namespace.c:1916 [inline] __do_sys_umount fs/namespace.c:1924 [inline] __se_sys_umount fs/namespace.c:1922 [inline] __x64_sys_umount+0x10e/0x1a0 fs/namespace.c:1922 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0x36/0x50 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+0x151/0x1a30 sound/core/pcm_native.c:740 snd_pcm_kernel_ioctl+0x147/0x2d0 sound/core/pcm_native.c:3434 snd_pcm_oss_change_params_locked+0x146c/0x3aa0 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+0xe6/0x1b0 sound/core/oss/pcm_oss.c:1164 snd_pcm_oss_get_odelay sound/core/oss/pcm_oss.c:2166 [inline] snd_pcm_oss_ioctl+0x155a/0x37a0 sound/core/oss/pcm_oss.c:2732 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:904 [inline] __se_sys_ioctl fs/ioctl.c:890 [inline] __x64_sys_ioctl+0x193/0x220 fs/ioctl.c:890 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 } ... key at: [] __key.5+0x0/0x40 ... acquired at: mark_usage kernel/locking/lockdep.c:4567 [inline] __lock_acquire+0x13d4/0x3b30 kernel/locking/lockdep.c:5091 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 _snd_pcm_stream_lock_irqsave+0xa0/0xd0 sound/core/pcm_native.c:170 class_pcm_stream_lock_irqsave_constructor include/sound/pcm.h:669 [inline] snd_pcm_period_elapsed+0x20/0x50 sound/core/pcm_lib.c:1904 dummy_hrtimer_callback+0x9d/0x1c0 sound/drivers/dummy.c:385 __run_hrtimer kernel/time/hrtimer.c:1692 [inline] __hrtimer_run_queues+0x20c/0xc20 kernel/time/hrtimer.c:1756 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1773 __do_softirq+0x218/0x8de kernel/softirq.c:554 invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu kernel/softirq.c:633 [inline] irq_exit_rcu+0xb9/0x120 kernel/softirq.c:645 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 check_kcov_mode kernel/kcov.c:173 [inline] __sanitizer_cov_trace_pc+0x18/0x60 kernel/kcov.c:207 __orc_find+0x63/0x130 arch/x86/kernel/unwind_orc.c:104 orc_find arch/x86/kernel/unwind_orc.c:227 [inline] unwind_next_frame+0x335/0x23a0 arch/x86/kernel/unwind_orc.c:494 arch_stack_walk+0x100/0x170 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122 __kfence_alloc+0x1bf/0x15d0 mm/kfence/core.c:1095 kfence_alloc include/linux/kfence.h:129 [inline] slab_alloc_node mm/slub.c:3831 [inline] kmem_cache_alloc+0x1de/0x320 mm/slub.c:3852 getname_flags.part.0+0x50/0x4f0 fs/namei.c:139 getname_flags+0x9b/0xf0 include/linux/audit.h:322 user_path_at_empty+0x2c/0x60 fs/namei.c:2920 user_path_at include/linux/namei.h:57 [inline] ksys_umount fs/namespace.c:1916 [inline] __do_sys_umount fs/namespace.c:1924 [inline] __se_sys_umount fs/namespace.c:1922 [inline] __x64_sys_umount+0x10e/0x1a0 fs/namespace.c:1922 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 stack backtrace: CPU: 1 PID: 5821 Comm: syz-executor.4 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+0x116/0x1f0 lib/dump_stack.c:114 print_irq_inversion_bug.part.0+0x3e9/0x5a0 kernel/locking/lockdep.c:4080 print_irq_inversion_bug kernel/locking/lockdep.c:4033 [inline] check_usage_forwards kernel/locking/lockdep.c:4111 [inline] mark_lock_irq kernel/locking/lockdep.c:4243 [inline] mark_lock+0x574/0xc60 kernel/locking/lockdep.c:4678 mark_usage kernel/locking/lockdep.c:4567 [inline] __lock_acquire+0x13d4/0x3b30 kernel/locking/lockdep.c:5091 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 _snd_pcm_stream_lock_irqsave+0xa0/0xd0 sound/core/pcm_native.c:170 class_pcm_stream_lock_irqsave_constructor include/sound/pcm.h:669 [inline] snd_pcm_period_elapsed+0x20/0x50 sound/core/pcm_lib.c:1904 dummy_hrtimer_callback+0x9d/0x1c0 sound/drivers/dummy.c:385 __run_hrtimer kernel/time/hrtimer.c:1692 [inline] __hrtimer_run_queues+0x20c/0xc20 kernel/time/hrtimer.c:1756 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1773 __do_softirq+0x218/0x8de kernel/softirq.c:554 invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu kernel/softirq.c:633 [inline] irq_exit_rcu+0xb9/0x120 kernel/softirq.c:645 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__sanitizer_cov_trace_pc+0x18/0x60 kernel/kcov.c:203 Code: 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 65 48 8b 15 04 db 76 7e 65 8b 05 05 db 76 7e a9 00 01 ff 00 <48> 8b 34 24 74 0f f6 c4 01 74 35 8b 82 14 16 00 00 85 c0 74 2b 8b RSP: 0018:ffffc9000386f898 EFLAGS: 00000246 RAX: 0000000080000001 RBX: ffffffff8fb7fd58 RCX: ffffffff813c8bf4 RDX: ffff888025195a00 RSI: ffffffff81fa6fbf RDI: 0000000000000006 RBP: ffffffff8fb7fd7c R08: 0000000000000006 R09: ffffffff81fa6fbf R10: ffffffff81fa6f7b R11: 0000000000000001 R12: ffffffff81fa6fbf R13: ffffffff81fa6f7b R14: dffffc0000000000 R15: ffffffff8fb7fd68 __orc_find+0x63/0x130 arch/x86/kernel/unwind_orc.c:104 orc_find arch/x86/kernel/unwind_orc.c:227 [inline] unwind_next_frame+0x335/0x23a0 arch/x86/kernel/unwind_orc.c:494 arch_stack_walk+0x100/0x170 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122 __kfence_alloc+0x1bf/0x15d0 mm/kfence/core.c:1095 kfence_alloc include/linux/kfence.h:129 [inline] slab_alloc_node mm/slub.c:3831 [inline] kmem_cache_alloc+0x1de/0x320 mm/slub.c:3852 getname_flags.part.0+0x50/0x4f0 fs/namei.c:139 getname_flags+0x9b/0xf0 include/linux/audit.h:322 user_path_at_empty+0x2c/0x60 fs/namei.c:2920 user_path_at include/linux/namei.h:57 [inline] ksys_umount fs/namespace.c:1916 [inline] __do_sys_umount fs/namespace.c:1924 [inline] __se_sys_umount fs/namespace.c:1922 [inline] __x64_sys_umount+0x10e/0x1a0 fs/namespace.c:1922 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 RIP: 0033:0x7f7979a7f197 Code: b0 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 b0 ff ff ff f7 d8 64 89 02 b8 RSP: 002b:00007ffd7ddf8648 EFLAGS: 00000206 ORIG_RAX: 00000000000000a6 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7979a7f197 RDX: 0000000000000000 RSI: 000000000000000a RDI: 00007ffd7ddf8700 RBP: 00007ffd7ddf8700 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000206 R12: 00007ffd7ddf97c0 R13: 00007f7979ac93b9 R14: 000000000002fa33 R15: 0000000000000016 TCP: request_sock_subflow_v4: Possible SYN flooding on port [::]:20002. Sending cookies. TCP: request_sock_subflow_v4: Possible SYN flooding on port [::]:20002. Sending cookies. TCP: request_sock_subflow_v4: Possible SYN flooding on port [::]:20002. Sending cookies. vkms_vblank_simulate: vblank timer overrun ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: 90 nop 3: 90 nop 4: 90 nop 5: 90 nop 6: 90 nop 7: 90 nop 8: 90 nop 9: 90 nop a: 90 nop b: 90 nop c: 90 nop d: 90 nop e: 90 nop f: 90 nop 10: 90 nop 11: 90 nop 12: f3 0f 1e fa endbr64 16: 65 48 8b 15 04 db 76 mov %gs:0x7e76db04(%rip),%rdx # 0x7e76db22 1d: 7e 1e: 65 8b 05 05 db 76 7e mov %gs:0x7e76db05(%rip),%eax # 0x7e76db2a 25: a9 00 01 ff 00 test $0xff0100,%eax * 2a: 48 8b 34 24 mov (%rsp),%rsi <-- trapping instruction 2e: 74 0f je 0x3f 30: f6 c4 01 test $0x1,%ah 33: 74 35 je 0x6a 35: 8b 82 14 16 00 00 mov 0x1614(%rdx),%eax 3b: 85 c0 test %eax,%eax 3d: 74 2b je 0x6a 3f: 8b .byte 0x8b