[ OK ] Started Getty on tty4. [ OK ] Started Getty on tty3. [ OK ] Started Getty on tty2. [ OK ] Started Serial Getty on ttyS0. [ OK ] Started Getty on tty1. [ OK ] Reached target Login Prompts. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Update UTMP about System Runlevel Changes. Starting Load/Save RF Kill Switch Status... Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.190' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 65.341574][ C1] [ 65.343917][ C1] ======================================================== [ 65.351114][ C1] WARNING: possible irq lock inversion dependency detected [ 65.358279][ C1] 5.9.0-rc4-next-20200911-syzkaller #0 Not tainted [ 65.364789][ C1] -------------------------------------------------------- [ 65.371952][ C1] swapper/1/0 just changed the state of lock: [ 65.378110][ C1] ffff888214db3908 (&group->lock){..-.}-{2:2}, at: _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 65.387995][ C1] but this lock took another, SOFTIRQ-READ-unsafe lock in the past: [ 65.395944][ C1] (&card->ctl_files_rwlock){.+.+}-{2:2} [ 65.395955][ C1] [ 65.395955][ C1] [ 65.395955][ C1] and interrupts could create inverse lock ordering between them. [ 65.395955][ C1] [ 65.415826][ C1] [ 65.415826][ C1] other info that might help us debug this: [ 65.423863][ C1] Possible interrupt unsafe locking scenario: [ 65.423863][ C1] [ 65.432163][ C1] CPU0 CPU1 [ 65.437500][ C1] ---- ---- [ 65.442836][ C1] lock(&card->ctl_files_rwlock); [ 65.447928][ C1] local_irq_disable(); [ 65.454740][ C1] lock(&group->lock); [ 65.461396][ C1] lock(&card->ctl_files_rwlock); [ 65.468995][ C1] [ 65.472422][ C1] lock(&group->lock); [ 65.476724][ C1] [ 65.476724][ C1] *** DEADLOCK *** [ 65.476724][ C1] [ 65.485366][ C1] 1 lock held by swapper/1/0: [ 65.490022][ C1] #0: ffffc90000da8d80 ((&dpcm->timer)){+.-.}-{0:0}, at: call_timer_fn+0xd5/0x6b0 [ 65.499294][ C1] [ 65.499294][ C1] the shortest dependencies between 2nd lock and 1st lock: [ 65.508644][ C1] -> (&card->ctl_files_rwlock){.+.+}-{2:2} { [ 65.514699][ C1] HARDIRQ-ON-R at: [ 65.518746][ C1] lock_acquire+0x1f2/0xaa0 [ 65.525058][ C1] _raw_read_lock+0x5b/0x70 [ 65.531361][ C1] snd_ctl_notify.part.0+0x36/0x550 [ 65.538395][ C1] snd_ctl_notify+0x8f/0xb0 [ 65.544696][ C1] __snd_ctl_add_replace+0x638/0x800 [ 65.552078][ C1] snd_ctl_add_replace+0x76/0x130 [ 65.558915][ C1] snd_dummy_probe+0xbbf/0x1050 [ 65.565571][ C1] platform_drv_probe+0x87/0x140 [ 65.572303][ C1] really_probe+0x282/0x9f0 [ 65.578609][ C1] driver_probe_device+0xfe/0x1d0 [ 65.586660][ C1] __device_attach_driver+0x1c2/0x220 [ 65.593826][ C1] bus_for_each_drv+0x15f/0x1e0 [ 65.600469][ C1] __device_attach+0x228/0x470 [ 65.607035][ C1] bus_probe_device+0x1e4/0x290 [ 65.613693][ C1] device_add+0xb17/0x1c40 [ 65.621121][ C1] platform_device_add+0x34f/0x6d0 [ 65.628047][ C1] platform_device_register_full+0x38c/0x4e0 [ 65.635821][ C1] alsa_card_dummy_init+0x1cc/0x2e0 [ 65.642814][ C1] do_one_initcall+0x103/0x6f0 [ 65.649370][ C1] kernel_init_freeable+0x5e9/0x66d [ 65.656360][ C1] kernel_init+0xd/0x1c0 [ 65.662412][ C1] ret_from_fork+0x1f/0x30 [ 65.668617][ C1] SOFTIRQ-ON-R at: [ 65.672665][ C1] lock_acquire+0x1f2/0xaa0 [ 65.678962][ C1] _raw_read_lock+0x5b/0x70 [ 65.685272][ C1] snd_ctl_notify.part.0+0x36/0x550 [ 65.692264][ C1] snd_ctl_notify+0x8f/0xb0 [ 65.698570][ C1] __snd_ctl_add_replace+0x638/0x800 [ 65.705646][ C1] snd_ctl_add_replace+0x76/0x130 [ 65.712471][ C1] snd_dummy_probe+0xbbf/0x1050 [ 65.719116][ C1] platform_drv_probe+0x87/0x140 [ 65.725857][ C1] really_probe+0x282/0x9f0 [ 65.732166][ C1] driver_probe_device+0xfe/0x1d0 [ 65.738983][ C1] __device_attach_driver+0x1c2/0x220 [ 65.746160][ C1] bus_for_each_drv+0x15f/0x1e0 [ 65.752804][ C1] __device_attach+0x228/0x470 [ 65.759359][ C1] bus_probe_device+0x1e4/0x290 [ 65.766000][ C1] device_add+0xb17/0x1c40 [ 65.772210][ C1] platform_device_add+0x34f/0x6d0 [ 65.779127][ C1] platform_device_register_full+0x38c/0x4e0 [ 65.787001][ C1] alsa_card_dummy_init+0x1cc/0x2e0 [ 65.794006][ C1] do_one_initcall+0x103/0x6f0 [ 65.800572][ C1] kernel_init_freeable+0x5e9/0x66d [ 65.807586][ C1] kernel_init+0xd/0x1c0 [ 65.813648][ C1] ret_from_fork+0x1f/0x30 [ 65.819879][ C1] (null) at: [ 65.823444][ C1] general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN [ 65.835138][ C1] KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] [ 65.843535][ C1] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.9.0-rc4-next-20200911-syzkaller #0 [ 65.852619][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 65.862681][ C1] RIP: 0010:print_shortest_lock_dependencies.cold+0x110/0x2af [ 65.870109][ C1] 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 [ 65.889689][ C1] RSP: 0018:ffffc90000da8898 EFLAGS: 00010003 [ 65.895741][ C1] RAX: 0000000000000001 RBX: ffffffff8cbdd190 RCX: 0000000000000000 [ 65.903700][ C1] RDX: 0000000000000002 RSI: ffffffff815c0ec7 RDI: 0000000000000015 [ 65.911647][ C1] RBP: ffffc90000da89c8 R08: 0000000000000004 R09: ffff8880ae720f8b [ 65.919590][ C1] R10: 0000000000000000 R11: 6c756e2820202020 R12: dffffc0000000000 [ 65.927548][ C1] R13: ffffffff8c9e73f8 R14: 0000000000000009 R15: 0000000000000001 [ 65.935512][ C1] FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 [ 65.944418][ C1] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 65.950980][ C1] CR2: 00000000200000c0 CR3: 0000000095c86000 CR4: 00000000001506e0 [ 65.958954][ C1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 65.966914][ C1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 65.974859][ C1] Call Trace: [ 65.978125][ C1] [ 65.980957][ C1] print_irq_inversion_bug.part.0+0x2c6/0x2ee [ 65.987020][ C1] mark_lock.cold+0x38/0x10d [ 65.991588][ C1] ? lock_chain_count+0x20/0x20 [ 65.996410][ C1] ? lock_is_held_type+0xbb/0xf0 [ 66.001319][ C1] ? find_held_lock+0x2d/0x110 [ 66.006056][ C1] ? debug_object_activate+0x287/0x3e0 [ 66.011499][ C1] ? lock_downgrade+0x830/0x830 [ 66.016331][ C1] __lock_acquire+0x117d/0x55d0 [ 66.021168][ C1] ? lock_downgrade+0x830/0x830 [ 66.026000][ C1] ? lockdep_hardirqs_on_prepare+0x530/0x530 [ 66.031957][ C1] ? mark_lock+0xf7/0x2300 [ 66.036345][ C1] lock_acquire+0x1f2/0xaa0 [ 66.040851][ C1] ? _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 66.046725][ C1] ? lock_release+0x890/0x890 [ 66.051426][ C1] ? find_held_lock+0x2d/0x110 [ 66.056182][ C1] ? loopback_jiffies_timer_function+0x188/0x220 [ 66.062503][ C1] ? _raw_spin_lock_irqsave+0xa9/0xd0 [ 66.067855][ C1] _raw_spin_lock_irqsave+0x94/0xd0 [ 66.073034][ C1] ? _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 66.078910][ C1] _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 66.084609][ C1] snd_pcm_period_elapsed+0x24/0x250 [ 66.090317][ C1] loopback_jiffies_timer_function+0x1a8/0x220 [ 66.096457][ C1] ? loopback_jiffies_timer_pos_update+0xf60/0xf60 [ 66.102934][ C1] call_timer_fn+0x1a5/0x6b0 [ 66.107504][ C1] ? add_timer_on+0x450/0x450 [ 66.112169][ C1] ? lock_downgrade+0x830/0x830 [ 66.117004][ C1] ? _raw_spin_unlock_irq+0x1f/0x80 [ 66.122175][ C1] ? loopback_jiffies_timer_pos_update+0xf60/0xf60 [ 66.128654][ C1] __run_timers.part.0+0x67c/0xa50 [ 66.133737][ C1] ? call_timer_fn+0x6b0/0x6b0 [ 66.138472][ C1] ? lapic_next_event+0x4d/0x80 [ 66.143305][ C1] ? clockevents_program_event+0x12b/0x350 [ 66.149095][ C1] ? kvm_sched_clock_read+0x14/0x40 [ 66.154284][ C1] ? sched_clock+0x2a/0x40 [ 66.158670][ C1] ? sched_clock_cpu+0x18/0x1b0 [ 66.163494][ C1] ? hrtimer_interrupt+0x6ea/0x930 [ 66.168576][ C1] run_timer_softirq+0xae/0x1a0 [ 66.173417][ C1] __do_softirq+0x202/0xa42 [ 66.177909][ C1] asm_call_on_stack+0xf/0x20 [ 66.182554][ C1] [ 66.185504][ C1] do_softirq_own_stack+0x9d/0xd0 [ 66.190503][ C1] irq_exit_rcu+0x235/0x280 [ 66.194984][ C1] sysvec_apic_timer_interrupt+0x51/0xf0 [ 66.200591][ C1] asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 66.206549][ C1] RIP: 0010:native_safe_halt+0xe/0x10 [ 66.211896][ C1] 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 [ 66.231479][ C1] RSP: 0018:ffffc90000d3fd10 EFLAGS: 00000293 [ 66.237674][ C1] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 1ffffffff15cacb9 [ 66.245715][ C1] RDX: ffff8880a9630340 RSI: ffffffff88034020 RDI: 0000000000000000 [ 66.253665][ C1] RBP: ffff8880a6274064 R08: 0000000000000001 R09: 0000000000000001 [ 66.261657][ C1] R10: 0000000000000000 R11: 0000000000000001 R12: ffff8880a6274064 [ 66.269605][ C1] R13: 1ffff920001a7fac R14: ffff8880a6274065 R15: 0000000000000001 [ 66.277568][ C1] ? acpi_safe_halt+0x90/0x180 [ 66.283203][ C1] acpi_safe_halt+0x95/0x180 [ 66.287784][ C1] acpi_idle_do_entry+0x15c/0x1b0 [ 66.292784][ C1] acpi_idle_enter+0x403/0xac0 [ 66.297524][ C1] ? acpi_idle_enter_bm+0x2d0/0x2d0 [ 66.302703][ C1] cpuidle_enter_state+0x150/0xa70 [ 66.307795][ C1] ? tick_nohz_idle_stop_tick+0x504/0xbc0 [ 66.313495][ C1] cpuidle_enter+0x4a/0xa0 [ 66.318008][ C1] do_idle+0x48e/0x730 [ 66.322068][ C1] ? arch_cpu_idle_exit+0x70/0x70 [ 66.327069][ C1] ? _raw_write_unlock_irqrestore+0x71/0x90 [ 66.332943][ C1] ? lockdep_hardirqs_on+0x53/0x100 [ 66.338115][ C1] cpu_startup_entry+0x14/0x20 [ 66.342876][ C1] secondary_startup_64_no_verify+0xa6/0xab [ 66.348750][ C1] Modules linked in: [ 66.352626][ C1] ---[ end trace b1fbfaefd3d77ad4 ]--- [ 66.358058][ C1] RIP: 0010:print_shortest_lock_dependencies.cold+0x110/0x2af [ 66.365486][ C1] 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 [ 66.385166][ C1] RSP: 0018:ffffc90000da8898 EFLAGS: 00010003 [ 66.391224][ C1] RAX: 0000000000000001 RBX: ffffffff8cbdd190 RCX: 0000000000000000 [ 66.399169][ C1] RDX: 0000000000000002 RSI: ffffffff815c0ec7 RDI: 0000000000000015 [ 66.407115][ C1] RBP: ffffc90000da89c8 R08: 0000000000000004 R09: ffff8880ae720f8b [ 66.415075][ C1] R10: 0000000000000000 R11: 6c756e2820202020 R12: dffffc0000000000 [ 66.423033][ C1] R13: ffffffff8c9e73f8 R14: 0000000000000009 R15: 0000000000000001 [ 66.431104][ C1] FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 [ 66.440002][ C1] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 66.446559][ C1] CR2: 00000000200000c0 CR3: 0000000095c86000 CR4: 00000000001506e0 [ 66.454510][ C1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 66.462454][ C1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 66.470403][ C1] Kernel panic - not syncing: Fatal exception in interrupt [ 66.478583][ C1] Kernel Offset: disabled [ 66.482899][ C1] Rebooting in 86400 seconds..