[ OK ] Started Getty on tty2. [ OK ] Started Getty on tty1. [ OK ] Started Serial Getty on ttyS0. [ 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... [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.1.0' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 66.950284][ C1] [ 66.952722][ C1] ======================================================== [ 66.959883][ C1] WARNING: possible irq lock inversion dependency detected [ 66.967056][ C1] 5.9.0-rc4-next-20200911-syzkaller #0 Not tainted [ 66.973545][ C1] -------------------------------------------------------- [ 66.980707][ C1] swapper/1/0 just changed the state of lock: [ 66.986738][ C1] ffff88809a290908 (&group->lock){..-.}-{2:2}, at: _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 66.996630][ C1] but this lock took another, SOFTIRQ-READ-unsafe lock in the past: [ 67.004571][ C1] (&card->ctl_files_rwlock){.+.+}-{2:2} [ 67.004583][ C1] [ 67.004583][ C1] [ 67.004583][ C1] and interrupts could create inverse lock ordering between them. [ 67.004583][ C1] [ 67.024555][ C1] [ 67.024555][ C1] other info that might help us debug this: [ 67.032585][ C1] Possible interrupt unsafe locking scenario: [ 67.032585][ C1] [ 67.040894][ C1] CPU0 CPU1 [ 67.046239][ C1] ---- ---- [ 67.051573][ C1] lock(&card->ctl_files_rwlock); [ 67.056656][ C1] local_irq_disable(); [ 67.063380][ C1] lock(&group->lock); [ 67.070037][ C1] lock(&card->ctl_files_rwlock); [ 67.077639][ C1] [ 67.081064][ C1] lock(&group->lock); [ 67.085366][ C1] [ 67.085366][ C1] *** DEADLOCK *** [ 67.085366][ C1] [ 67.093499][ C1] 1 lock held by swapper/1/0: [ 67.098139][ C1] #0: ffffc90000da8d80 ((&dpcm->timer)){+.-.}-{0:0}, at: call_timer_fn+0xd5/0x6b0 [ 67.107415][ C1] [ 67.107415][ C1] the shortest dependencies between 2nd lock and 1st lock: [ 67.116800][ C1] -> (&card->ctl_files_rwlock){.+.+}-{2:2} { [ 67.122848][ C1] HARDIRQ-ON-R at: [ 67.126897][ C1] lock_acquire+0x1f2/0xaa0 [ 67.133205][ C1] _raw_read_lock+0x5b/0x70 [ 67.139504][ C1] snd_ctl_notify.part.0+0x36/0x550 [ 67.146495][ C1] snd_ctl_notify+0x8f/0xb0 [ 67.152805][ C1] __snd_ctl_add_replace+0x638/0x800 [ 67.159971][ C1] snd_ctl_add_replace+0x76/0x130 [ 67.166803][ C1] snd_dummy_probe+0xbbf/0x1050 [ 67.173452][ C1] platform_drv_probe+0x87/0x140 [ 67.180185][ C1] really_probe+0x282/0x9f0 [ 67.186508][ C1] driver_probe_device+0xfe/0x1d0 [ 67.193342][ C1] __device_attach_driver+0x1c2/0x220 [ 67.200523][ C1] bus_for_each_drv+0x15f/0x1e0 [ 67.207173][ C1] __device_attach+0x228/0x470 [ 67.213742][ C1] bus_probe_device+0x1e4/0x290 [ 67.220386][ C1] device_add+0xb17/0x1c40 [ 67.226611][ C1] platform_device_add+0x34f/0x6d0 [ 67.233522][ C1] platform_device_register_full+0x38c/0x4e0 [ 67.241297][ C1] alsa_card_dummy_init+0x1cc/0x2e0 [ 67.248301][ C1] do_one_initcall+0x103/0x6f0 [ 67.254871][ C1] kernel_init_freeable+0x5e9/0x66d [ 67.261864][ C1] kernel_init+0xd/0x1c0 [ 67.267997][ C1] ret_from_fork+0x1f/0x30 [ 67.274205][ C1] SOFTIRQ-ON-R at: [ 67.278262][ C1] lock_acquire+0x1f2/0xaa0 [ 67.284561][ C1] _raw_read_lock+0x5b/0x70 [ 67.290868][ C1] snd_ctl_notify.part.0+0x36/0x550 [ 67.297899][ C1] snd_ctl_notify+0x8f/0xb0 [ 67.304206][ C1] __snd_ctl_add_replace+0x638/0x800 [ 67.311292][ C1] snd_ctl_add_replace+0x76/0x130 [ 67.318125][ C1] snd_dummy_probe+0xbbf/0x1050 [ 67.324770][ C1] platform_drv_probe+0x87/0x140 [ 67.331501][ C1] really_probe+0x282/0x9f0 [ 67.337797][ C1] driver_probe_device+0xfe/0x1d0 [ 67.344626][ C1] __device_attach_driver+0x1c2/0x220 [ 67.351792][ C1] bus_for_each_drv+0x15f/0x1e0 [ 67.358435][ C1] __device_attach+0x228/0x470 [ 67.365000][ C1] bus_probe_device+0x1e4/0x290 [ 67.371655][ C1] device_add+0xb17/0x1c40 [ 67.377865][ C1] platform_device_add+0x34f/0x6d0 [ 67.384768][ C1] platform_device_register_full+0x38c/0x4e0 [ 67.392554][ C1] alsa_card_dummy_init+0x1cc/0x2e0 [ 67.399559][ C1] do_one_initcall+0x103/0x6f0 [ 67.406129][ C1] kernel_init_freeable+0x5e9/0x66d [ 67.413225][ C1] kernel_init+0xd/0x1c0 [ 67.419276][ C1] ret_from_fork+0x1f/0x30 [ 67.425480][ C1] (null) at: [ 67.429022][ C1] general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN [ 67.440715][ C1] KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] [ 67.449107][ C1] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.9.0-rc4-next-20200911-syzkaller #0 [ 67.458178][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 67.468222][ C1] RIP: 0010:print_shortest_lock_dependencies.cold+0x110/0x2af [ 67.475685][ 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 [ 67.495277][ C1] RSP: 0018:ffffc90000da8898 EFLAGS: 00010003 [ 67.501329][ C1] RAX: 0000000000000001 RBX: ffffffff8cbddf90 RCX: 0000000000000000 [ 67.509286][ C1] RDX: 0000000000000002 RSI: ffffffff815c0ec7 RDI: 0000000000000015 [ 67.517245][ C1] RBP: ffffc90000da89c8 R08: 0000000000000004 R09: ffff8880ae720f8b [ 67.525208][ C1] R10: 0000000000000000 R11: 6c756e2820202020 R12: dffffc0000000000 [ 67.533150][ C1] R13: ffffffff8c9e74b0 R14: 0000000000000009 R15: 0000000000000001 [ 67.541094][ C1] FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 [ 67.550002][ C1] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 67.556586][ C1] CR2: 0000000020000dc0 CR3: 0000000009c8e000 CR4: 00000000001506e0 [ 67.564544][ C1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 67.572494][ C1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 67.580437][ C1] Call Trace: [ 67.583691][ C1] [ 67.586536][ C1] print_irq_inversion_bug.part.0+0x2c6/0x2ee [ 67.592589][ C1] mark_lock.cold+0x38/0x10d [ 67.597164][ C1] ? lock_chain_count+0x20/0x20 [ 67.601984][ C1] ? lock_is_held_type+0xbb/0xf0 [ 67.606893][ C1] ? find_held_lock+0x2d/0x110 [ 67.611631][ C1] ? debug_object_activate+0x287/0x3e0 [ 67.617081][ C1] ? lock_downgrade+0x830/0x830 [ 67.621920][ C1] __lock_acquire+0x117d/0x55d0 [ 67.626756][ C1] ? lock_downgrade+0x830/0x830 [ 67.631578][ C1] ? lockdep_hardirqs_on_prepare+0x530/0x530 [ 67.637529][ C1] ? mark_lock+0xf7/0x2300 [ 67.641929][ C1] lock_acquire+0x1f2/0xaa0 [ 67.646419][ C1] ? _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 67.652307][ C1] ? lock_release+0x890/0x890 [ 67.656967][ C1] ? find_held_lock+0x2d/0x110 [ 67.661705][ C1] ? loopback_jiffies_timer_function+0x188/0x220 [ 67.668023][ C1] ? _raw_spin_lock_irqsave+0xa9/0xd0 [ 67.673368][ C1] _raw_spin_lock_irqsave+0x94/0xd0 [ 67.678553][ C1] ? _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 67.684427][ C1] _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 67.690136][ C1] snd_pcm_period_elapsed+0x24/0x250 [ 67.695405][ C1] loopback_jiffies_timer_function+0x1a8/0x220 [ 67.701545][ C1] ? loopback_jiffies_timer_pos_update+0xf60/0xf60 [ 67.708014][ C1] call_timer_fn+0x1a5/0x6b0 [ 67.712576][ C1] ? add_timer_on+0x450/0x450 [ 67.717226][ C1] ? lock_downgrade+0x830/0x830 [ 67.722075][ C1] ? rwlock_bug.part.0+0x90/0x90 [ 67.726986][ C1] ? _raw_spin_unlock_irq+0x1f/0x80 [ 67.732163][ C1] ? loopback_jiffies_timer_pos_update+0xf60/0xf60 [ 67.738648][ C1] __run_timers.part.0+0x67c/0xa50 [ 67.743752][ C1] ? call_timer_fn+0x6b0/0x6b0 [ 67.748500][ C1] ? lapic_next_event+0x4d/0x80 [ 67.753327][ C1] ? clockevents_program_event+0x12b/0x350 [ 67.759107][ C1] ? kvm_sched_clock_read+0x14/0x40 [ 67.764276][ C1] ? sched_clock+0x2a/0x40 [ 67.768663][ C1] ? sched_clock_cpu+0x18/0x1b0 [ 67.773498][ C1] ? hrtimer_interrupt+0x6ea/0x930 [ 67.778582][ C1] run_timer_softirq+0xae/0x1a0 [ 67.783427][ C1] __do_softirq+0x202/0xa42 [ 67.787915][ C1] asm_call_on_stack+0xf/0x20 [ 67.792561][ C1] [ 67.795478][ C1] do_softirq_own_stack+0x9d/0xd0 [ 67.800483][ C1] irq_exit_rcu+0x235/0x280 [ 67.804985][ C1] sysvec_apic_timer_interrupt+0x51/0xf0 [ 67.810603][ C1] asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 67.816556][ C1] RIP: 0010:native_safe_halt+0xe/0x10 [ 67.821898][ 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 [ 67.841484][ C1] RSP: 0018:ffffc90000d3fd10 EFLAGS: 00000293 [ 67.847525][ C1] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 1ffffffff15cacb9 [ 67.855479][ C1] RDX: ffff8880a9630340 RSI: ffffffff88034020 RDI: 0000000000000000 [ 67.863422][ C1] RBP: ffff8880a630e864 R08: 0000000000000001 R09: 0000000000000001 [ 67.871379][ C1] R10: 0000000000000000 R11: 0000000000000001 R12: ffff8880a630e864 [ 67.879322][ C1] R13: 1ffff920001a7fac R14: ffff8880a630e865 R15: 0000000000000001 [ 67.887275][ C1] ? acpi_safe_halt+0x90/0x180 [ 67.892014][ C1] acpi_safe_halt+0x95/0x180 [ 67.896588][ C1] acpi_idle_do_entry+0x15c/0x1b0 [ 67.901586][ C1] acpi_idle_enter+0x403/0xac0 [ 67.906323][ C1] ? acpi_idle_enter_bm+0x2d0/0x2d0 [ 67.911495][ C1] cpuidle_enter_state+0x150/0xa70 [ 67.916589][ C1] ? tick_nohz_idle_stop_tick+0x504/0xbc0 [ 67.922279][ C1] cpuidle_enter+0x4a/0xa0 [ 67.926670][ C1] do_idle+0x48e/0x730 [ 67.930712][ C1] ? arch_cpu_idle_exit+0x70/0x70 [ 67.935716][ C1] ? _raw_write_unlock_irqrestore+0x71/0x90 [ 67.941589][ C1] ? lockdep_hardirqs_on+0x53/0x100 [ 67.946758][ C1] cpu_startup_entry+0x14/0x20 [ 67.951495][ C1] secondary_startup_64_no_verify+0xa6/0xab [ 67.957355][ C1] Modules linked in: [ 67.961231][ C1] ---[ end trace 2d7a1e29c56aded1 ]--- [ 67.966665][ C1] RIP: 0010:print_shortest_lock_dependencies.cold+0x110/0x2af [ 67.974103][ 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 [ 67.994215][ C1] RSP: 0018:ffffc90000da8898 EFLAGS: 00010003 [ 68.000257][ C1] RAX: 0000000000000001 RBX: ffffffff8cbddf90 RCX: 0000000000000000 [ 68.008199][ C1] RDX: 0000000000000002 RSI: ffffffff815c0ec7 RDI: 0000000000000015 [ 68.016143][ C1] RBP: ffffc90000da89c8 R08: 0000000000000004 R09: ffff8880ae720f8b [ 68.024088][ C1] R10: 0000000000000000 R11: 6c756e2820202020 R12: dffffc0000000000 [ 68.032029][ C1] R13: ffffffff8c9e74b0 R14: 0000000000000009 R15: 0000000000000001 [ 68.039987][ C1] FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 [ 68.048898][ C1] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 68.055452][ C1] CR2: 0000000020000dc0 CR3: 0000000009c8e000 CR4: 00000000001506e0 [ 68.063437][ C1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 68.071411][ C1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 68.079368][ C1] Kernel panic - not syncing: Fatal exception in interrupt [ 68.087729][ C1] Kernel Offset: disabled [ 68.092044][ C1] Rebooting in 86400 seconds..