[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [ 26.385297] kauditd_printk_skb: 7 callbacks suppressed [ 26.385308] audit: type=1800 audit(1538207335.166:29): pid=5214 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rc.local" dev="sda1" ino=2432 res=0 [ 26.418339] audit: type=1800 audit(1538207335.166:30): pid=5214 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rmnologin" dev="sda1" ino=2423 res=0 Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.84' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 575.362960] INFO: task jbd2/sda1-8:3077 blocked for more than 140 seconds. [ 575.370202] Not tainted 4.19.0-rc5+ #236 [ 575.376042] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 575.384135] jbd2/sda1-8 D18264 3077 2 0x80000000 [ 575.389816] Call Trace: [ 575.392489] __schedule+0x86c/0x1ed0 [ 575.396373] ? __sched_text_start+0x8/0x8 [ 575.400573] ? mark_held_locks+0xc7/0x130 [ 575.404858] ? graph_lock+0x170/0x170 [ 575.408702] ? _raw_spin_unlock_irqrestore+0x82/0xd0 [ 575.413944] ? _raw_spin_unlock_irqrestore+0x82/0xd0 [ 575.419061] ? lockdep_hardirqs_on+0x421/0x5c0 [ 575.423792] ? trace_hardirqs_on+0xbd/0x310 [ 575.428156] ? kasan_check_read+0x11/0x20 [ 575.432341] ? prepare_to_wait+0x1b3/0x3f0 [ 575.436734] ? __bpf_trace_preemptirq_template+0x30/0x30 [ 575.442203] ? find_held_lock+0x36/0x1c0 [ 575.446412] schedule+0xfe/0x460 [ 575.449790] ? lock_downgrade+0x900/0x900 [ 575.454066] ? __schedule+0x1ed0/0x1ed0 [ 575.458056] ? kasan_check_read+0x11/0x20 [ 575.462257] ? do_raw_spin_unlock+0xa7/0x2f0 [ 575.466812] ? do_raw_write_trylock+0x1c0/0x1c0 [ 575.471504] ? kasan_check_write+0x14/0x20 [ 575.475869] ? do_raw_spin_lock+0xc1/0x200 [ 575.480176] jbd2_journal_commit_transaction+0xd42/0x89f8 [ 575.485857] ? print_usage_bug+0xc0/0xc0 [ 575.489956] ? journal_submit_commit_record+0xb60/0xb60 [ 575.495530] ? __lock_acquire+0x7ec/0x4ec0 [ 575.499777] ? mark_held_locks+0x130/0x130 [ 575.505121] ? __update_load_avg_blocked_se+0x730/0x730 [ 575.510505] ? __update_load_avg_se+0xb90/0xb90 [ 575.515336] ? __lock_is_held+0xb5/0x140 [ 575.519501] ? update_load_avg+0x387/0x2470 [ 575.524042] ? print_usage_bug+0xc0/0xc0 [ 575.528117] ? kasan_check_write+0x14/0x20 [ 575.532359] ? native_queued_spin_lock_slowpath+0x1de/0x1120 [ 575.538293] ? __bfs+0xb0/0x7a0 [ 575.542063] ? finish_wait+0x430/0x430 [ 575.546083] ? __pv_queued_spin_lock_slowpath+0x15d0/0x15d0 [ 575.551820] ? __lock_acquire+0x7ec/0x4ec0 [ 575.556184] ? graph_lock+0x170/0x170 [ 575.560091] ? print_usage_bug+0xc0/0xc0 [ 575.564230] ? mark_held_locks+0x130/0x130 [ 575.568520] ? find_held_lock+0x36/0x1c0 [ 575.572612] ? print_usage_bug+0xc0/0xc0 [ 575.576841] ? __lock_acquire+0x7ec/0x4ec0 [ 575.581166] ? rcu_read_unlock_special.part.39+0x11f0/0x11f0 [ 575.587151] ? kasan_check_read+0x11/0x20 [ 575.591312] ? rcu_dynticks_curr_cpu_in_eqs+0x9f/0x160 [ 575.596744] ? rcu_bh_qs+0xc0/0xc0 [ 575.600323] ? __lock_acquire+0x7ec/0x4ec0 [ 575.604765] ? mark_held_locks+0x130/0x130 [ 575.610831] ? update_curr+0x4ec/0xbe0 [ 575.614858] ? print_usage_bug+0xc0/0xc0 [ 575.618932] ? graph_lock+0x170/0x170 [ 575.622884] ? __account_cfs_rq_runtime+0x790/0x790 [ 575.627921] ? mark_held_locks+0x130/0x130 [ 575.632193] ? graph_lock+0x170/0x170 [ 575.637183] ? print_usage_bug+0xc0/0xc0 [ 575.641265] ? pick_next_task_fair+0xbad/0x17c0 [ 575.646076] ? lock_downgrade+0x900/0x900 [ 575.650242] ? graph_lock+0x170/0x170 [ 575.654177] ? print_usage_bug+0xc0/0xc0 [ 575.658252] ? lock_is_held_type+0x210/0x210 [ 575.662676] ? __lock_acquire+0x7ec/0x4ec0 [ 575.667055] ? find_held_lock+0x36/0x1c0 [ 575.671137] ? find_held_lock+0x36/0x1c0 [ 575.675356] ? __lock_acquire+0x7ec/0x4ec0 [ 575.679602] ? __lock_acquire+0x7ec/0x4ec0 [ 575.683958] ? kasan_check_read+0x11/0x20 [ 575.688174] ? finish_task_switch+0x1f5/0x900 [ 575.692678] ? __bpf_trace_preemptirq_template+0x30/0x30 [ 575.698334] ? compat_start_thread+0x80/0x80 [ 575.702873] ? mark_held_locks+0x130/0x130 [ 575.707121] ? mark_held_locks+0x130/0x130 [ 575.711353] ? kasan_check_write+0x14/0x20 [ 575.715725] ? finish_task_switch+0x2f5/0x900 [ 575.720230] ? graph_lock+0x170/0x170 [ 575.724158] ? preempt_notifier_register+0x200/0x200 [ 575.729310] ? __switch_to_asm+0x34/0x70 [ 575.733514] ? __switch_to_asm+0x34/0x70 [ 575.737607] ? __switch_to_asm+0x34/0x70 [ 575.741673] ? __switch_to_asm+0x40/0x70 [ 575.745873] ? __switch_to_asm+0x34/0x70 [ 575.749944] ? __switch_to_asm+0x40/0x70 [ 575.754154] ? __switch_to_asm+0x34/0x70 [ 575.758225] ? __switch_to_asm+0x34/0x70 [ 575.762289] ? __switch_to_asm+0x40/0x70 [ 575.767528] ? __switch_to_asm+0x34/0x70 [ 575.771611] ? graph_lock+0x170/0x170 [ 575.775721] ? lock_acquire+0x1ed/0x520 [ 575.779752] ? lock_timer_base+0xbb/0x2b0 [ 575.784039] ? _raw_spin_unlock_irqrestore+0x82/0xd0 [ 575.789155] ? find_held_lock+0x36/0x1c0 [ 575.793359] ? try_to_del_timer_sync+0xec/0x140 [ 575.798040] ? _raw_spin_unlock_irqrestore+0x82/0xd0 [ 575.803266] ? _raw_spin_unlock_irqrestore+0x82/0xd0 [ 575.808405] ? lockdep_hardirqs_on+0x421/0x5c0 [ 575.813114] ? trace_hardirqs_on+0xbd/0x310 [ 575.817448] ? kasan_check_read+0x11/0x20 [ 575.821608] ? try_to_del_timer_sync+0xec/0x140 [ 575.826476] ? __bpf_trace_preemptirq_template+0x30/0x30 [ 575.831940] ? stub_timer+0x10/0x10 [ 575.835711] ? del_timer_sync+0xf8/0x270 [ 575.839789] ? _raw_spin_unlock_irqrestore+0x6d/0xd0 [ 575.845020] ? try_to_del_timer_sync+0xec/0x140 [ 575.849699] ? del_timer+0x150/0x150 [ 575.853646] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 575.859203] kjournald2+0x26d/0xb30 [ 575.862984] ? __bpf_trace_jbd2_end_commit+0x30/0x30 [ 575.868099] ? __kthread_parkme+0xce/0x1a0 [ 575.872345] ? _raw_spin_unlock_irqrestore+0x82/0xd0 [ 575.877617] ? _raw_spin_unlock_irqrestore+0x82/0xd0 [ 575.882862] ? lockdep_hardirqs_on+0x421/0x5c0 [ 575.887456] ? trace_hardirqs_on+0xbd/0x310 [ 575.891794] ? finish_wait+0x430/0x430 [ 575.896832] ? __bpf_trace_preemptirq_template+0x30/0x30 [ 575.902299] ? kasan_check_write+0x14/0x20 [ 575.906675] ? do_raw_spin_lock+0xc1/0x200 [ 575.910930] ? _raw_spin_unlock_irqrestore+0x6d/0xd0 [ 575.916161] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 575.921708] ? __kthread_parkme+0xfb/0x1a0 [ 575.926080] kthread+0x35a/0x420 [ 575.929496] ? __bpf_trace_jbd2_end_commit+0x30/0x30 [ 575.934735] ? kthread_bind+0x40/0x40 [ 575.938722] ret_from_fork+0x3a/0x50 [ 575.942460] [ 575.942460] Showing all locks held in the system: [ 575.948937] 4 locks held by kworker/u4:0/7: [ 575.953393] #0: 00000000e9b0ee7f ((wq_completion)"writeback"){+.+.}, at: process_one_work+0xb43/0x1b90 [ 575.963102] #1: 00000000d8d01f0a ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0xb9a/0x1b90 [ 575.973844] #2: 0000000039cb045e (&type->s_umount_key#30){++++}, at: trylock_super+0x22/0x110 [ 575.982698] #3: 00000000df4bcb0f (&sbi->s_journal_flag_rwsem){.+.+}, at: do_writepages+0x9a/0x1a0 [ 575.992010] 1 lock held by khungtaskd/982: [ 575.996383] #0: 0000000003f27341 (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x424 [ 576.005221] 3 locks held by rs:main Q:Reg/5250: [ 576.009894] #0: 000000003c407fc9 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 [ 576.018101] #1: 0000000096d047a6 (sb_writers#3){.+.+}, at: vfs_write+0x42a/0x560 [ 576.026863] #2: 000000002618d05d (&sb->s_type->i_mutex_key#10){+.+.}, at: ext4_file_write_iter+0x2a1/0x1420 [ 576.037067] 1 lock held by rsyslogd/5252: [ 576.041216] #0: 000000007a1b6ecb (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 [ 576.049387] 2 locks held by getty/5342: [ 576.053487] #0: 00000000e88cb0ef (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 [ 576.061761] #1: 000000003dccf44d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 576.070855] 2 locks held by getty/5343: [ 576.074941] #0: 00000000a8fb49e8 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 [ 576.083343] #1: 00000000f91322ef (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 576.092227] 2 locks held by getty/5344: [ 576.096327] #0: 000000007849223c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 [ 576.104709] #1: 00000000fe36a5ae (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 576.113729] 2 locks held by getty/5345: [ 576.117704] #0: 000000003f24454a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 [ 576.126092] #1: 0000000067e1119a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 576.135091] 2 locks held by getty/5346: [ 576.139064] #0: 000000003532e72c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 [ 576.147484] #1: 0000000015c2ef0f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 576.157497] 2 locks held by getty/5347: [ 576.161479] #0: 00000000eb297d1e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 [ 576.169870] #1: 00000000dd35ae8a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 576.178873] 2 locks held by getty/5348: [ 576.182971] #0: 00000000c5effe49 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 [ 576.191265] #1: 00000000da053980 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 576.200285] 6 locks held by syz-executor608/5371: [ 576.205240] [ 576.206875] ============================================= [ 576.206875] [ 576.214018] NMI backtrace for cpu 0 [ 576.217657] CPU: 0 PID: 982 Comm: khungtaskd Not tainted 4.19.0-rc5+ #236 [ 576.224577] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 576.233923] Call Trace: [ 576.236581] dump_stack+0x1c4/0x2b4 [ 576.240234] ? dump_stack_print_info.cold.2+0x52/0x52 [ 576.245450] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 576.251022] nmi_cpu_backtrace.cold.3+0x63/0xa2 [ 576.255757] ? lapic_can_unplug_cpu.cold.27+0x3f/0x3f [ 576.260966] nmi_trigger_cpumask_backtrace+0x1b3/0x1ed [ 576.266254] arch_trigger_cpumask_backtrace+0x14/0x20 [ 576.271475] watchdog+0xb3e/0x1050 [ 576.275034] ? reset_hung_task_detector+0xd0/0xd0 [ 576.279887] ? __kthread_parkme+0xce/0x1a0 [ 576.284131] ? _raw_spin_unlock_irqrestore+0x82/0xd0 [ 576.289239] ? _raw_spin_unlock_irqrestore+0x82/0xd0 [ 576.294358] ? lockdep_hardirqs_on+0x421/0x5c0 [ 576.298948] ? trace_hardirqs_on+0xbd/0x310 [ 576.303277] ? kasan_check_read+0x11/0x20 [ 576.307428] ? __kthread_parkme+0xce/0x1a0 [ 576.311664] ? __bpf_trace_preemptirq_template+0x30/0x30 [ 576.317117] ? kasan_check_write+0x14/0x20 [ 576.321358] ? do_raw_spin_lock+0xc1/0x200 [ 576.325608] ? _raw_spin_unlock_irqrestore+0x6d/0xd0 [ 576.330717] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 576.336290] ? __kthread_parkme+0xfb/0x1a0 [ 576.340533] kthread+0x35a/0x420 [ 576.343905] ? reset_hung_task_detector+0xd0/0xd0 [ 576.348748] ? kthread_bind+0x40/0x40 [ 576.352553] ret_from_fork+0x3a/0x50 [ 576.356412] Sending NMI from CPU 0 to CPUs 1: [ 576.362292] INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.231 msecs [ 576.362925] NMI backtrace for cpu 1 [ 576.362933] CPU: 1 PID: 5371 Comm: syz-executor608 Not tainted 4.19.0-rc5+ #236 [ 576.362941] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 576.362946] RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x50 [ 576.362960] Code: 14 dd 28 00 00 00 4d 39 d0 72 1b 49 83 c1 01 4a 89 7c 10 e0 4a 89 74 10 e8 4a 89 54 10 f0 4a 89 4c d8 20 4c 89 08 5d c3 66 90 <55> 48 89 e5 65 48 8b 04 25 40 ee 01 00 65 8b 15 3c 38 83 7e 81 e2 [ 576.362965] RSP: 0018:ffff8801d9a7f148 EFLAGS: 00000216 [ 576.362974] RAX: 0000000000000006 RBX: ffff8801d9589180 RCX: ffffffff8211004c [ 576.362981] RDX: 0000000000000000 RSI: ffffffff8211005b RDI: 0000000000000003 [ 576.362987] RBP: ffff8801d9a7f1b0 R08: ffff8801bb276140 R09: 1ffffffff1273955 [ 576.362993] R10: ffffed003b5e4732 R11: ffff8801daf23993 R12: 0000000000000001 [ 576.362999] R13: ffff8801b76ba058 R14: ffff8801b76ba04c R15: ffff8801d9589180 [ 576.363006] FS: 00000000018cb940(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 [ 576.363012] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 576.363018] CR2: 0000000020000180 CR3: 00000001d7aa1000 CR4: 00000000001406e0 [ 576.363024] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 576.363031] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 576.363034] Call Trace: [ 576.363038] ? ext4_find_extent+0x5c6/0x9b0 [ 576.363043] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 576.363048] mext_check_coverage.constprop.13+0x2b0/0x510 [ 576.363053] ? mext_page_mkuptodate+0x12b0/0x12b0 [ 576.363058] ext4_move_extents+0x2784/0x3c20 [ 576.363063] ? ext4_double_up_write_data_sem+0x30/0x30 [ 576.363068] ? rcu_read_lock_sched_held+0x108/0x120 [ 576.363072] ? kmem_cache_free+0x24f/0x290 [ 576.363076] ? jbd2_journal_stop+0x234/0x15d0 [ 576.363082] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 576.363086] ? ext4_reserve_inode_write+0x148/0x260 [ 576.363092] ? __bpf_trace_preemptirq_template+0x30/0x30 [ 576.363096] ? ext4_alloc_file_blocks+0x50b/0xaf0 [ 576.363101] ? graph_lock+0x170/0x170 [ 576.363105] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 576.363110] ? graph_lock+0x170/0x170 [ 576.363115] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 576.363119] ? inode_init_owner+0x340/0x340 [ 576.363123] ? graph_lock+0x170/0x170 [ 576.363128] ? check_preemption_disabled+0x48/0x200 [ 576.363133] ? check_preemption_disabled+0x48/0x200 [ 576.363137] ? __lock_is_held+0xb5/0x140 [ 576.363142] ? rcu_read_lock_sched_held+0x108/0x120 [ 576.363146] ? preempt_count_add+0x7d/0x160 [ 576.363152] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 576.363156] ? __mnt_want_write_file+0xa2/0xc0 [ 576.363161] ext4_ioctl+0x3154/0x4210 [ 576.363165] ? ext4_ioctl_group_add+0x560/0x560 [ 576.363169] ? graph_lock+0x170/0x170 [ 576.363173] ? graph_lock+0x170/0x170 [ 576.363178] ? ext4_insert_range+0x1410/0x1410 [ 576.363183] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 576.363188] ? __generic_file_write_iter+0x1bd/0x630 [ 576.363192] ? find_held_lock+0x36/0x1c0 [ 576.363196] ? vfs_fallocate+0x7ab/0x940 [ 576.363201] ? lock_downgrade+0x900/0x900 [ 576.363205] ? __lock_is_held+0xb5/0x140 [ 576.363210] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 576.363215] ? check_preemption_disabled+0x48/0x200 [ 576.363220] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 576.363224] ? __fget_light+0x2e9/0x430 [ 576.363228] ? fget_raw+0x20/0x20 [ 576.363233] ? ioctl_preallocate+0x145/0x300 [ 576.363238] ? ioctl_file_clone+0x2c0/0x2c0 [ 576.363242] ? vfs_write+0x2f3/0x560 [ 576.363247] ? ext4_ioctl_group_add+0x560/0x560 [ 576.363251] do_vfs_ioctl+0x1de/0x1720 [ 576.363255] ? sockfd_lookup_light+0xc5/0x160 [ 576.363260] ? ioctl_preallocate+0x300/0x300 [ 576.363265] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 576.363269] ? __fget_light+0x2e9/0x430 [ 576.363279] ? fget_raw+0x20/0x20 [ 576.363283] ? __sb_end_write+0xd9/0x110 [ 576.363288] ? do_syscall_64+0x9a/0x820 [ 576.363292] ? do_syscall_64+0x9a/0x820 [ 576.363297] ? lockdep_hardirqs_on+0x421/0x5c0 [ 576.363301] ? security_file_ioctl+0x94/0xc0 [ 576.363305] ksys_ioctl+0xa9/0xd0 [ 576.363309] __x64_sys_ioctl+0x73/0xb0 [ 576.363313] do_syscall_64+0x1b9/0x820 [ 576.363318] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 576.363323] ? syscall_return_slowpath+0x5e0/0x5e0 [ 576.363328] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 576.363333] ? trace_hardirqs_on_caller+0x310/0x310 [ 576.363338] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 576.363343] ? prepare_exit_to_usermode+0x291/0x3b0 [ 576.363348] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 576.363353] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 576.363357] RIP: 0033:0x440ee9 [ 576.363370] Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 576.363375] RSP: 002b:00007ffd02ddb818 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 576.363386] RAX: ffffffffffffffda RBX: 00007ffd02ddb820 RCX: 0000000000440ee9 [ 576.363392] RDX: 0000000020000300 RSI: 00000000c028660f RDI: 0000000000000003 [ 576.363398] RBP: 0000000000000000 R08: 00000000004009ae R09: 00000000004009ae [ 576.363404] R10: 00000000004009ae R11: 0000000000000246 R12: 0000000000402770 [ 576.363411] R13: 0000000000402800 R14: 0000000000000000 R15: 0000000000000000 [ 576.365665] Kernel panic - not syncing: hung_task: blocked tasks [ 576.877777] CPU: 0 PID: 982 Comm: khungtaskd Not tainted 4.19.0-rc5+ #236 [ 576.884699] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 576.894048] Call Trace: [ 576.896646] dump_stack+0x1c4/0x2b4 [ 576.900285] ? dump_stack_print_info.cold.2+0x52/0x52 [ 576.905558] panic+0x238/0x4e7 [ 576.908757] ? add_taint.cold.5+0x16/0x16 [ 576.912918] ? nmi_trigger_cpumask_backtrace+0x16a/0x1ed [ 576.918372] ? nmi_trigger_cpumask_backtrace+0x1c4/0x1ed [ 576.923823] ? nmi_trigger_cpumask_backtrace+0x173/0x1ed [ 576.929281] ? nmi_trigger_cpumask_backtrace+0x16a/0x1ed [ 576.934741] watchdog+0xb4f/0x1050 [ 576.938304] ? reset_hung_task_detector+0xd0/0xd0 [ 576.943153] ? __kthread_parkme+0xce/0x1a0 [ 576.947392] ? _raw_spin_unlock_irqrestore+0x82/0xd0 [ 576.952500] ? _raw_spin_unlock_irqrestore+0x82/0xd0 [ 576.957609] ? lockdep_hardirqs_on+0x421/0x5c0 [ 576.962193] ? trace_hardirqs_on+0xbd/0x310 [ 576.966518] ? kasan_check_read+0x11/0x20 [ 576.970668] ? __kthread_parkme+0xce/0x1a0 [ 576.974908] ? __bpf_trace_preemptirq_template+0x30/0x30 [ 576.980361] ? kasan_check_write+0x14/0x20 [ 576.984603] ? do_raw_spin_lock+0xc1/0x200 [ 576.988844] ? _raw_spin_unlock_irqrestore+0x6d/0xd0 [ 576.993953] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 576.999499] ? __kthread_parkme+0xfb/0x1a0 [ 577.003742] kthread+0x35a/0x420 [ 577.007111] ? reset_hung_task_detector+0xd0/0xd0 [ 577.011951] ? kthread_bind+0x40/0x40 [ 577.015757] ret_from_fork+0x3a/0x50 [ 577.020605] Kernel Offset: disabled [ 577.024235] Rebooting in 86400 seconds..