[ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Load/Save RF Kill Switch Status. [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.10.56' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 68.389608][ C0] [ 68.391961][ C0] ======================================================== [ 68.399436][ C0] WARNING: possible irq lock inversion dependency detected [ 68.406645][ C0] 5.9.0-rc4-next-20200911-syzkaller #0 Not tainted [ 68.413122][ C0] -------------------------------------------------------- [ 68.420334][ C0] swapper/0/0 just changed the state of lock: [ 68.426387][ C0] ffff888214d91108 (&group->lock){..-.}-{2:2}, at: _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 68.436301][ C0] but this lock took another, SOFTIRQ-READ-unsafe lock in the past: [ 68.444253][ C0] (&card->ctl_files_rwlock){.+.+}-{2:2} [ 68.444266][ C0] [ 68.444266][ C0] [ 68.444266][ C0] and interrupts could create inverse lock ordering between them. [ 68.444266][ C0] [ 68.465554][ C0] [ 68.465554][ C0] other info that might help us debug this: [ 68.473844][ C0] Possible interrupt unsafe locking scenario: [ 68.473844][ C0] [ 68.482184][ C0] CPU0 CPU1 [ 68.487552][ C0] ---- ---- [ 68.492920][ C0] lock(&card->ctl_files_rwlock); [ 68.498014][ C0] local_irq_disable(); [ 68.504770][ C0] lock(&group->lock); [ 68.511597][ C0] lock(&card->ctl_files_rwlock); [ 68.519223][ C0] [ 68.522651][ C0] lock(&group->lock); [ 68.526954][ C0] [ 68.526954][ C0] *** DEADLOCK *** [ 68.526954][ C0] [ 68.535089][ C0] 1 lock held by swapper/0/0: [ 68.539741][ C0] #0: ffffc90000007d80 ((&dpcm->timer)){+.-.}-{0:0}, at: call_timer_fn+0xd5/0x6b0 [ 68.549367][ C0] [ 68.549367][ C0] the shortest dependencies between 2nd lock and 1st lock: [ 68.558832][ C0] -> (&card->ctl_files_rwlock){.+.+}-{2:2} { [ 68.564997][ C0] HARDIRQ-ON-R at: [ 68.569064][ C0] lock_acquire+0x1f2/0xaa0 [ 68.575508][ C0] _raw_read_lock+0x5b/0x70 [ 68.581827][ C0] snd_ctl_notify.part.0+0x36/0x550 [ 68.588831][ C0] snd_ctl_notify+0x8f/0xb0 [ 68.595154][ C0] __snd_ctl_add_replace+0x638/0x800 [ 68.602417][ C0] snd_ctl_add_replace+0x76/0x130 [ 68.609257][ C0] snd_dummy_probe+0xbbf/0x1050 [ 68.615925][ C0] platform_drv_probe+0x87/0x140 [ 68.622669][ C0] really_probe+0x282/0x9f0 [ 68.628984][ C0] driver_probe_device+0xfe/0x1d0 [ 68.635825][ C0] __device_attach_driver+0x1c2/0x220 [ 68.643007][ C0] bus_for_each_drv+0x15f/0x1e0 [ 68.649663][ C0] __device_attach+0x228/0x470 [ 68.656232][ C0] bus_probe_device+0x1e4/0x290 [ 68.663346][ C0] device_add+0xb17/0x1c40 [ 68.669766][ C0] platform_device_add+0x34f/0x6d0 [ 68.676786][ C0] platform_device_register_full+0x38c/0x4e0 [ 68.684767][ C0] alsa_card_dummy_init+0x1cc/0x2e0 [ 68.691893][ C0] do_one_initcall+0x103/0x6f0 [ 68.698468][ C0] kernel_init_freeable+0x5e9/0x66d [ 68.705613][ C0] kernel_init+0xd/0x1c0 [ 68.711686][ C0] ret_from_fork+0x1f/0x30 [ 68.717896][ C0] SOFTIRQ-ON-R at: [ 68.722084][ C0] lock_acquire+0x1f2/0xaa0 [ 68.728412][ C0] _raw_read_lock+0x5b/0x70 [ 68.734724][ C0] snd_ctl_notify.part.0+0x36/0x550 [ 68.741722][ C0] snd_ctl_notify+0x8f/0xb0 [ 68.748046][ C0] __snd_ctl_add_replace+0x638/0x800 [ 68.755251][ C0] snd_ctl_add_replace+0x76/0x130 [ 68.762079][ C0] snd_dummy_probe+0xbbf/0x1050 [ 68.768745][ C0] platform_drv_probe+0x87/0x140 [ 68.776287][ C0] really_probe+0x282/0x9f0 [ 68.782879][ C0] driver_probe_device+0xfe/0x1d0 [ 68.789723][ C0] __device_attach_driver+0x1c2/0x220 [ 68.797182][ C0] bus_for_each_drv+0x15f/0x1e0 [ 68.803851][ C0] __device_attach+0x228/0x470 [ 68.810539][ C0] bus_probe_device+0x1e4/0x290 [ 68.817217][ C0] device_add+0xb17/0x1c40 [ 68.823466][ C0] platform_device_add+0x34f/0x6d0 [ 68.830390][ C0] platform_device_register_full+0x38c/0x4e0 [ 68.838346][ C0] alsa_card_dummy_init+0x1cc/0x2e0 [ 68.845395][ C0] do_one_initcall+0x103/0x6f0 [ 68.851995][ C0] kernel_init_freeable+0x5e9/0x66d [ 68.859005][ C0] kernel_init+0xd/0x1c0 [ 68.865069][ C0] ret_from_fork+0x1f/0x30 [ 68.871296][ C0] (null) at: [ 68.874851][ C0] general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN [ 68.886562][ C0] KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] [ 68.895135][ C0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.9.0-rc4-next-20200911-syzkaller #0 [ 68.904239][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 68.915272][ C0] RIP: 0010:print_shortest_lock_dependencies.cold+0x110/0x2af [ 68.922713][ C0] Code: 48 8b 04 24 48 c1 e8 03 42 80 3c 20 00 74 09 48 8b 3c 24 e8 5b 11 da f9 48 8b 04 24 48 8b 00 48 8d 78 14 48 89 fa 48 c1 ea 03 <42> 0f b6 0c 22 48 89 fa 83 e2 07 83 c2 03 38 ca 7c 08 84 c9 0f 85 [ 68.942306][ C0] RSP: 0018:ffffc90000007898 EFLAGS: 00010003 [ 68.948390][ C0] RAX: 0000000000000001 RBX: ffffffff8cbde380 RCX: 0000000000000000 [ 68.956637][ C0] RDX: 0000000000000002 RSI: ffffffff815c0ec7 RDI: 0000000000000015 [ 68.965318][ C0] RBP: ffffc900000079c8 R08: 0000000000000004 R09: ffff8880ae620f8b [ 68.973277][ C0] R10: 0000000000000000 R11: 6c756e2820202020 R12: dffffc0000000000 [ 68.981228][ C0] R13: ffffffff8c9e71d0 R14: 0000000000000009 R15: 0000000000000001 [ 68.989420][ C0] FS: 0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 [ 68.998327][ C0] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 69.004888][ C0] CR2: 0000000020000dc0 CR3: 00000000934e4000 CR4: 00000000001506f0 [ 69.012836][ C0] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 69.020895][ C0] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 69.028839][ C0] Call Trace: [ 69.032098][ C0] [ 69.034947][ C0] print_irq_inversion_bug.part.0+0x2c6/0x2ee [ 69.041001][ C0] mark_lock.cold+0x38/0x10d [ 69.045568][ C0] ? lock_chain_count+0x20/0x20 [ 69.050393][ C0] ? lock_is_held_type+0xbb/0xf0 [ 69.055358][ C0] ? find_held_lock+0x2d/0x110 [ 69.060106][ C0] ? debug_object_activate+0x287/0x3e0 [ 69.065575][ C0] ? lock_downgrade+0x830/0x830 [ 69.070401][ C0] __lock_acquire+0x117d/0x55d0 [ 69.075227][ C0] ? lock_downgrade+0x830/0x830 [ 69.080071][ C0] ? lockdep_hardirqs_on_prepare+0x530/0x530 [ 69.086023][ C0] ? mark_lock+0xf7/0x2300 [ 69.090422][ C0] lock_acquire+0x1f2/0xaa0 [ 69.094909][ C0] ? _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 69.100774][ C0] ? lock_release+0x890/0x890 [ 69.105419][ C0] ? find_held_lock+0x2d/0x110 [ 69.110249][ C0] ? loopback_jiffies_timer_function+0x188/0x220 [ 69.116928][ C0] ? _raw_spin_lock_irqsave+0xa9/0xd0 [ 69.122279][ C0] _raw_spin_lock_irqsave+0x94/0xd0 [ 69.127475][ C0] ? _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 69.133343][ C0] _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 69.139039][ C0] snd_pcm_period_elapsed+0x24/0x250 [ 69.144317][ C0] loopback_jiffies_timer_function+0x1a8/0x220 [ 69.150446][ C0] ? loopback_jiffies_timer_pos_update+0xf60/0xf60 [ 69.156930][ C0] call_timer_fn+0x1a5/0x6b0 [ 69.161510][ C0] ? add_timer_on+0x450/0x450 [ 69.166254][ C0] ? lock_downgrade+0x830/0x830 [ 69.171093][ C0] ? _raw_spin_unlock_irq+0x1f/0x80 [ 69.176298][ C0] ? loopback_jiffies_timer_pos_update+0xf60/0xf60 [ 69.182771][ C0] __run_timers.part.0+0x67c/0xa50 [ 69.187951][ C0] ? call_timer_fn+0x6b0/0x6b0 [ 69.192700][ C0] ? lapic_next_event+0x4d/0x80 [ 69.197523][ C0] ? clockevents_program_event+0x12b/0x350 [ 69.203314][ C0] ? kvm_sched_clock_read+0x14/0x40 [ 69.208485][ C0] ? sched_clock+0x2a/0x40 [ 69.212873][ C0] ? sched_clock_cpu+0x18/0x1b0 [ 69.217694][ C0] ? hrtimer_interrupt+0x6ea/0x930 [ 69.222777][ C0] run_timer_softirq+0xae/0x1a0 [ 69.227602][ C0] __do_softirq+0x202/0xa42 [ 69.232093][ C0] asm_call_on_stack+0xf/0x20 [ 69.236763][ C0] [ 69.239690][ C0] do_softirq_own_stack+0x9d/0xd0 [ 69.244691][ C0] irq_exit_rcu+0x235/0x280 [ 69.249170][ C0] sysvec_apic_timer_interrupt+0x51/0xf0 [ 69.254787][ C0] asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 69.260738][ C0] RIP: 0010:native_safe_halt+0xe/0x10 [ 69.266082][ C0] Code: ff 4c 89 ef e8 93 d9 af f9 e9 8e fe ff ff 48 89 df e8 86 d9 af f9 eb 8a cc cc cc cc e9 07 00 00 00 0f 00 2d 84 87 65 00 fb f4 90 e9 07 00 00 00 0f 00 2d 74 87 65 00 f4 c3 cc cc 55 53 e8 69 [ 69.285671][ C0] RSP: 0018:ffffffff89c07cd8 EFLAGS: 00000293 [ 69.291711][ C0] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 1ffffffff15cacb9 [ 69.299830][ C0] RDX: ffffffff89c9b040 RSI: ffffffff88034020 RDI: 0000000000000000 [ 69.307885][ C0] RBP: ffff8880a6798064 R08: 0000000000000001 R09: 0000000000000001 [ 69.315839][ C0] R10: 0000000000000000 R11: 0000000000000001 R12: ffff8880a6798064 [ 69.323800][ C0] R13: 1ffffffff1380fa5 R14: ffff8880a6798065 R15: 0000000000000001 [ 69.331760][ C0] ? acpi_safe_halt+0x90/0x180 [ 69.336502][ C0] acpi_safe_halt+0x95/0x180 [ 69.341076][ C0] acpi_idle_do_entry+0x15c/0x1b0 [ 69.346093][ C0] acpi_idle_enter+0x403/0xac0 [ 69.350833][ C0] ? acpi_idle_enter_bm+0x2d0/0x2d0 [ 69.356095][ C0] cpuidle_enter_state+0x150/0xa70 [ 69.361184][ C0] ? tick_nohz_idle_stop_tick+0x5af/0xbc0 [ 69.366884][ C0] cpuidle_enter+0x4a/0xa0 [ 69.371294][ C0] do_idle+0x48e/0x730 [ 69.375338][ C0] ? arch_cpu_idle_exit+0x70/0x70 [ 69.380349][ C0] ? trace_init_perf_perm_irq_work_exit+0xe/0xe [ 69.386561][ C0] cpu_startup_entry+0x14/0x20 [ 69.391565][ C0] start_kernel+0x490/0x4b1 [ 69.396058][ C0] secondary_startup_64_no_verify+0xa6/0xab [ 69.401930][ C0] Modules linked in: [ 69.405818][ C0] ---[ end trace d261a79243d60519 ]--- [ 69.411255][ C0] RIP: 0010:print_shortest_lock_dependencies.cold+0x110/0x2af [ 69.418682][ C0] Code: 48 8b 04 24 48 c1 e8 03 42 80 3c 20 00 74 09 48 8b 3c 24 e8 5b 11 da f9 48 8b 04 24 48 8b 00 48 8d 78 14 48 89 fa 48 c1 ea 03 <42> 0f b6 0c 22 48 89 fa 83 e2 07 83 c2 03 38 ca 7c 08 84 c9 0f 85 [ 69.438282][ C0] RSP: 0018:ffffc90000007898 EFLAGS: 00010003 [ 69.444323][ C0] RAX: 0000000000000001 RBX: ffffffff8cbde380 RCX: 0000000000000000 [ 69.452284][ C0] RDX: 0000000000000002 RSI: ffffffff815c0ec7 RDI: 0000000000000015 [ 69.460232][ C0] RBP: ffffc900000079c8 R08: 0000000000000004 R09: ffff8880ae620f8b [ 69.468306][ C0] R10: 0000000000000000 R11: 6c756e2820202020 R12: dffffc0000000000 [ 69.476251][ C0] R13: ffffffff8c9e71d0 R14: 0000000000000009 R15: 0000000000000001 [ 69.484272][ C0] FS: 0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 [ 69.493203][ C0] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 69.499759][ C0] CR2: 0000000020000dc0 CR3: 00000000934e4000 CR4: 00000000001506f0 [ 69.507726][ C0] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 69.515688][ C0] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 69.523999][ C0] Kernel panic - not syncing: Fatal exception in interrupt [ 69.533109][ C0] Kernel Offset: disabled [ 69.537604][ C0] Rebooting in 86400 seconds..