[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c.
[ 54.839271][ T26] audit: type=1800 audit(1572152778.931:25): pid=8606 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0
[ 54.866740][ T26] audit: type=1800 audit(1572152778.931:26): pid=8606 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0
[ 54.907507][ T26] audit: type=1800 audit(1572152778.931:27): pid=8606 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2436 res=0
[....] Starting periodic command scheduler: cron[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c.
[....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c.
Debian GNU/Linux 7 syzkaller ttyS0
Warning: Permanently added '10.128.1.53' (ECDSA) to the list of known hosts.
syzkaller login: [ 214.536507][ T1077] INFO: task kworker/u4:5:528 blocked for more than 143 seconds.
[ 214.544615][ T1077] Not tainted 5.4.0-rc4-next-20191025 #0
[ 214.551310][ T1077] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 214.560200][ T1077] kworker/u4:5 D24344 528 2 0x80004000
[ 214.566623][ T1077] Workqueue: writeback wb_workfn (flush-8:0)
[ 214.572604][ T1077] Call Trace:
[ 214.575979][ T1077] __schedule+0x94a/0x1e70
[ 214.580485][ T1077] ? __sched_text_start+0x8/0x8
[ 214.585352][ T1077] ? blk_insert_cloned_request+0x530/0x530
[ 214.591521][ T1077] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20
[ 214.597848][ T1077] ? kthread_data+0x58/0xc0
[ 214.602353][ T1077] schedule+0xdc/0x2b0
[ 214.607205][ T1077] io_schedule+0x1c/0x70
[ 214.611921][ T1077] __lock_page+0x422/0xab0
[ 214.616329][ T1077] ? wait_on_page_bit+0xa60/0xa60
[ 214.621778][ T1077] ? page_cache_next_miss+0x340/0x340
[ 214.627213][ T1077] ? ___might_sleep+0x163/0x2c0
[ 214.632180][ T1077] ? __might_sleep+0x95/0x190
[ 214.636950][ T1077] mpage_prepare_extent_to_map+0xb3f/0xf90
[ 214.642779][ T1077] ? mpage_process_page_bufs+0x780/0x780
[ 214.648564][ T1077] ? rcu_read_lock_sched_held+0x9c/0xd0
[ 214.654193][ T1077] ? rcu_read_lock_any_held.part.0+0x50/0x50
[ 214.660360][ T1077] ? kmem_cache_alloc_node_trace+0x4ef/0x750
[ 214.666370][ T1077] ext4_writepages+0x954/0x2e70
[ 214.671273][ T1077] ? ___might_sleep+0x163/0x2c0
[ 214.676155][ T1077] ? __might_sleep+0x80/0x190
[ 214.680945][ T1077] ? print_usage_bug+0xb2/0xd0
[ 214.685725][ T1077] ? ext4_mark_inode_dirty+0x9b0/0x9b0
[ 214.691345][ T1077] ? __kasan_check_read+0x11/0x20
[ 214.696378][ T1077] ? __lock_acquire+0x16f2/0x4a00
[ 214.701603][ T1077] ? __kasan_check_read+0x11/0x20
[ 214.706833][ T1077] ? mark_lock+0xc2/0x1220
[ 214.711268][ T1077] ? mark_held_locks+0xf0/0xf0
[ 214.716303][ T1077] ? __kasan_check_read+0x11/0x20
[ 214.721434][ T1077] ? ext4_mark_inode_dirty+0x9b0/0x9b0
[ 214.726950][ T1077] do_writepages+0xfa/0x2a0
[ 214.731473][ T1077] ? do_writepages+0xfa/0x2a0
[ 214.736152][ T1077] ? page_writeback_cpu_online+0x20/0x20
[ 214.742637][ T1077] ? rcu_lockdep_current_cpu_online+0xe3/0x130
[ 214.748976][ T1077] ? rcu_read_lock_sched_held+0x9c/0xd0
[ 214.754560][ T1077] ? rcu_read_lock_any_held.part.0+0x50/0x50
[ 214.760626][ T1077] __writeback_single_inode+0x136/0x1400
[ 214.766566][ T1077] ? _raw_spin_unlock+0x28/0x40
[ 214.771417][ T1077] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20
[ 214.777728][ T1077] ? wbc_attach_and_unlock_inode+0x5bf/0x920
[ 214.783716][ T1077] writeback_sb_inodes+0x596/0xf20
[ 214.788893][ T1077] ? __writeback_single_inode+0x1400/0x1400
[ 214.794801][ T1077] ? trylock_super+0x22/0x110
[ 214.799545][ T1077] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20
[ 214.805798][ T1077] __writeback_inodes_wb+0xc3/0x260
[ 214.811078][ T1077] wb_writeback+0x910/0xd90
[ 214.815597][ T1077] ? writeback_inodes_wb.constprop.0+0x1a0/0x1a0
[ 214.822020][ T1077] ? get_nr_dirty_inodes+0xe2/0x140
[ 214.827273][ T1077] wb_workfn+0xa8a/0x1220
[ 214.831617][ T1077] ? inode_wait_for_writeback+0x40/0x40
[ 214.837227][ T1077] ? rcu_lockdep_current_cpu_online+0xe3/0x130
[ 214.843534][ T1077] ? rcu_read_lock_any_held.part.0+0x50/0x50
[ 214.849689][ T1077] ? trace_hardirqs_on+0x67/0x240
[ 214.854815][ T1077] process_one_work+0x9af/0x1740
[ 214.859834][ T1077] ? pwq_dec_nr_in_flight+0x320/0x320
[ 214.865222][ T1077] ? lock_acquire+0x190/0x410
[ 214.870708][ T1077] worker_thread+0x98/0xe40
[ 214.875241][ T1077] kthread+0x361/0x430
[ 214.879369][ T1077] ? process_one_work+0x1740/0x1740
[ 214.884583][ T1077] ? kthread_mod_delayed_work+0x1f0/0x1f0
[ 214.890368][ T1077] ret_from_fork+0x24/0x30
[ 214.894810][ T1077] INFO: task khugepaged:1089 blocked for more than 143 seconds.
[ 214.902500][ T1077] Not tainted 5.4.0-rc4-next-20191025 #0
[ 214.908686][ T1077] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 214.917402][ T1077] khugepaged D27840 1089 2 0x80004000
[ 214.923739][ T1077] Call Trace:
[ 214.927078][ T1077] __schedule+0x94a/0x1e70
[ 214.931543][ T1077] ? __sched_text_start+0x8/0x8
[ 214.936388][ T1077] ? blk_insert_cloned_request+0x530/0x530
[ 214.942297][ T1077] ? _raw_spin_unlock_irq+0x23/0x80
[ 214.947528][ T1077] ? __lock_page+0x3d9/0xab0
[ 214.952118][ T1077] ? _raw_spin_unlock_irq+0x23/0x80
[ 214.957399][ T1077] schedule+0xdc/0x2b0
[ 214.961581][ T1077] io_schedule+0x1c/0x70
[ 214.965827][ T1077] __lock_page+0x422/0xab0
[ 214.970300][ T1077] ? wait_on_page_bit+0xa60/0xa60
[ 214.975334][ T1077] ? page_cache_next_miss+0x340/0x340
[ 214.980790][ T1077] ? ___might_sleep+0x163/0x2c0
[ 214.985662][ T1077] ? __might_sleep+0x95/0x190
[ 214.990576][ T1077] mpage_prepare_extent_to_map+0xb3f/0xf90
[ 214.996399][ T1077] ? mpage_process_page_bufs+0x780/0x780
[ 215.002853][ T1077] ? rcu_read_lock_any_held.part.0+0x50/0x50
[ 215.008881][ T1077] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20
[ 215.015126][ T1077] ext4_writepages+0xb6a/0x2e70
[ 215.020044][ T1077] ? __this_cpu_preempt_check+0x35/0x190
[ 215.025785][ T1077] ? ext4_mark_inode_dirty+0x9b0/0x9b0
[ 215.031282][ T1077] ? 0xffffffff81000000
[ 215.035450][ T1077] ? mark_lock+0xc2/0x1220
[ 215.039930][ T1077] ? prep_new_page+0x19f/0x200
[ 215.044880][ T1077] ? wbc_attach_and_unlock_inode+0x515/0x920
[ 215.050931][ T1077] ? find_held_lock+0x35/0x130
[ 215.055704][ T1077] ? wbc_attach_and_unlock_inode+0x515/0x920
[ 215.061759][ T1077] ? ext4_mark_inode_dirty+0x9b0/0x9b0
[ 215.067295][ T1077] do_writepages+0xfa/0x2a0
[ 215.071810][ T1077] ? do_writepages+0xfa/0x2a0
[ 215.076554][ T1077] ? lock_downgrade+0x920/0x920
[ 215.081413][ T1077] ? page_writeback_cpu_online+0x20/0x20
[ 215.087089][ T1077] ? __kasan_check_read+0x11/0x20
[ 215.092114][ T1077] ? do_raw_spin_unlock+0x57/0x270
[ 215.097316][ T1077] ? _raw_spin_unlock+0x28/0x40
[ 215.102173][ T1077] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20
[ 215.108467][ T1077] ? wbc_attach_and_unlock_inode+0x5bf/0x920
[ 215.114460][ T1077] __filemap_fdatawrite_range+0x2bc/0x3b0
[ 215.120270][ T1077] ? delete_from_page_cache_batch+0xfe0/0xfe0
[ 215.126355][ T1077] ? lockdep_hardirqs_on+0x421/0x5e0
[ 215.132442][ T1077] filemap_flush+0x24/0x30
[ 215.136958][ T1077] collapse_file+0x36b1/0x41a0
[ 215.141758][ T1077] ? rcu_lockdep_current_cpu_online+0xe3/0x130
[ 215.148019][ T1077] ? khugepaged+0x21d0/0x4360
[ 215.152705][ T1077] ? trace_event_raw_event_mm_collapse_huge_page_isolate+0x370/0x370
[ 215.160856][ T1077] ? __sanitizer_cov_trace_cmp4+0x16/0x20
[ 215.166631][ T1077] ? khugepaged_find_target_node+0x142/0x180
[ 215.172602][ T1077] khugepaged+0x2da9/0x4360
[ 215.177166][ T1077] ? __kasan_check_read+0x11/0x20
[ 215.182195][ T1077] ? __lock_acquire+0x16f2/0x4a00
[ 215.187410][ T1077] ? collapse_pte_mapped_thp+0xbe0/0xbe0
[ 215.193051][ T1077] ? lock_downgrade+0x920/0x920
[ 215.197993][ T1077] ? finish_wait+0x260/0x260
[ 215.202591][ T1077] ? lockdep_hardirqs_on+0x421/0x5e0
[ 215.207924][ T1077] ? trace_hardirqs_on+0x67/0x240
[ 215.212981][ T1077] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20
[ 215.219294][ T1077] ? __kthread_parkme+0x108/0x1c0
[ 215.225293][ T1077] ? __kasan_check_read+0x11/0x20
[ 215.230426][ T1077] kthread+0x361/0x430
[ 215.234507][ T1077] ? collapse_pte_mapped_thp+0xbe0/0xbe0
[ 215.240260][ T1077] ? kthread_mod_delayed_work+0x1f0/0x1f0
[ 215.246010][ T1077] ret_from_fork+0x24/0x30
[ 215.250574][ T1077]
[ 215.250574][ T1077] Showing all locks held in the system:
[ 215.259055][ T1077] 4 locks held by kworker/u4:5/528:
[ 215.264250][ T1077] #0: ffff8880a78a0d28 ((wq_completion)writeback){+.+.}, at: process_one_work+0x88b/0x1740
[ 215.274404][ T1077] #1: ffff8880a855fdc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0x8c1/0x1740
[ 215.285779][ T1077] #2: ffff8882158460d8 (&type->s_umount_key#32){++++}, at: trylock_super+0x22/0x110
[ 215.295441][ T1077] #3: ffff888215848990 (&sbi->s_journal_flag_rwsem){.+.+}, at: do_writepages+0xfa/0x2a0
[ 215.305323][ T1077] 1 lock held by khungtaskd/1077:
[ 215.310384][ T1077] #0: ffffffff88faba80 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x279
[ 215.319760][ T1077] 1 lock held by khugepaged/1089:
[ 215.324791][ T1077] #0: ffff888215848990 (&sbi->s_journal_flag_rwsem){.+.+}, at: do_writepages+0xfa/0x2a0
[ 215.334698][ T1077] 2 locks held by rsyslogd/8644:
[ 215.339703][ T1077] #0: ffff88809a1230e0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110
[ 215.348478][ T1077] #1: ffffffff88fbaa08 (tk_core.seq){----}, at: is_bpf_text_address+0x0/0x160
[ 215.357546][ T1077] 2 locks held by getty/8734:
[ 215.362250][ T1077] #0: ffff8880a7897090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40
[ 215.371258][ T1077] #1: ffffc90005f252e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0
[ 215.380893][ T1077] 2 locks held by getty/8735:
[ 215.385560][ T1077] #0: ffff8880a7db3090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40
[ 215.395302][ T1077] #1: ffffc90005f432e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0
[ 215.404943][ T1077] 2 locks held by getty/8736:
[ 215.409650][ T1077] #0: ffff8880a70d8090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40
[ 215.418677][ T1077] #1: ffffc90005f292e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0
[ 215.428287][ T1077] 2 locks held by getty/8737:
[ 215.432952][ T1077] #0: ffff88809209a090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40
[ 215.442145][ T1077] #1: ffffc90005f3f2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0
[ 215.451739][ T1077] 2 locks held by getty/8738:
[ 215.456478][ T1077] #0: ffff8880a8ee6090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40
[ 215.465442][ T1077] #1: ffffc90005f312e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0
[ 215.475072][ T1077] 2 locks held by getty/8739:
[ 215.479799][ T1077] #0: ffff8880a8166090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40
[ 215.489147][ T1077] #1: ffffc90005f1d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0
[ 215.498774][ T1077] 2 locks held by getty/8740:
[ 215.503435][ T1077] #0: ffff8880a1bd4090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40
[ 215.512426][ T1077] #1: ffffc90005f112e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0
[ 215.522757][ T1077] 1 lock held by syz-execprog/8758:
[ 215.528067][ T1077] #0: ffff8880977e1428 (&ei->i_mmap_sem){++++}, at: ext4_filemap_fault+0x7e/0xb2
[ 215.537585][ T1077]
[ 215.539906][ T1077] =============================================
[ 215.539906][ T1077]
[ 215.548360][ T1077] NMI backtrace for cpu 1
[ 215.552689][ T1077] CPU: 1 PID: 1077 Comm: khungtaskd Not tainted 5.4.0-rc4-next-20191025 #0
[ 215.561302][ T1077] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 215.571352][ T1077] Call Trace:
[ 215.574635][ T1077] dump_stack+0x172/0x1f0
[ 215.578966][ T1077] nmi_cpu_backtrace.cold+0x70/0xb2
[ 215.584141][ T1077] ? vprintk_func+0x86/0x189
[ 215.588735][ T1077] ? lapic_can_unplug_cpu.cold+0x3a/0x3a
[ 215.594381][ T1077] nmi_trigger_cpumask_backtrace+0x23b/0x28b
[ 215.600351][ T1077] arch_trigger_cpumask_backtrace+0x14/0x20
[ 215.606247][ T1077] watchdog+0xc8f/0x1350
[ 215.610484][ T1077] kthread+0x361/0x430
[ 215.614545][ T1077] ? reset_hung_task_detector+0x30/0x30
[ 215.620106][ T1077] ? kthread_mod_delayed_work+0x1f0/0x1f0
[ 215.625817][ T1077] ret_from_fork+0x24/0x30
[ 215.630315][ T1077] Sending NMI from CPU 1 to CPUs 0:
[ 215.636113][ C0] NMI backtrace for cpu 0
[ 215.636118][ C0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.4.0-rc4-next-20191025 #0
[ 215.636124][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 215.636128][ C0] RIP: 0010:check_memory_region+0x126/0x1a0
[ 215.636138][ C0] Code: 49 29 c1 e9 68 ff ff ff 5b b8 01 00 00 00 41 5c 41 5d 5d c3 4d 85 c9 74 ef 4d 01 e1 eb 09 48 83 c0 01 4c 39 c8 74 e1 80 38 00 <74> f2 eb 8c 4d 39 c2 74 4d e8 8c e4 ff ff 31 c0 5b 41 5c 41 5d 5d
[ 215.636141][ C0] RSP: 0018:ffff8880ae809b50 EFLAGS: 00000046
[ 215.636148][ C0] RAX: ffffed1015d06b7c RBX: ffffed1015d06b7d RCX: ffffffff81612834
[ 215.636153][ C0] RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8880ae835be0
[ 215.636157][ C0] RBP: ffff8880ae809b68 R08: 1ffff11015d06b7c R09: ffffed1015d06b7d
[ 215.636162][ C0] R10: ffffed1015d06b7c R11: ffff8880ae835be3 R12: ffffed1015d06b7c
[ 215.636166][ C0] R13: ffff8880ae834d40 R14: 0000000000000010 R15: ffff8880a9813000
[ 215.636171][ C0] FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
[ 215.636175][ C0] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 215.636180][ C0] CR2: 0000000001dc5000 CR3: 00000000a1bb5000 CR4: 00000000001406f0
[ 215.636184][ C0] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 215.636189][ C0] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 215.636191][ C0] Call Trace:
[ 215.636194][ C0]
[ 215.636197][ C0] __kasan_check_read+0x11/0x20
[ 215.636200][ C0] rcu_dynticks_curr_cpu_in_eqs+0x54/0xb0
[ 215.636204][ C0] rcu_is_watching+0x10/0x30
[ 215.636207][ C0] rcu_read_lock_held_common+0xb4/0x130
[ 215.636210][ C0] rcu_read_lock_held+0x5b/0xb0
[ 215.636214][ C0] ? rcu_read_lock_held_common+0x130/0x130
[ 215.636217][ C0] select_task_rq_fair+0x7e9/0x1810
[ 215.636221][ C0] try_to_wake_up+0x435/0x1ab0
[ 215.636224][ C0] ? migrate_swap_stop+0x9f0/0x9f0
[ 215.636227][ C0] ? rcu_read_lock_sched_held+0x9c/0xd0
[ 215.636231][ C0] wake_up_process+0x10/0x20
[ 215.636234][ C0] hrtimer_wakeup+0x48/0x60
[ 215.636237][ C0] __hrtimer_run_queues+0x364/0xe40
[ 215.636241][ C0] ? hrtimer_init_sleeper_on_stack+0xa0/0xa0
[ 215.636244][ C0] ? hrtimer_init+0x330/0x330
[ 215.636248][ C0] ? __sanitizer_cov_trace_cmp4+0x16/0x20
[ 215.636252][ C0] ? ktime_get_update_offsets_now+0x2ce/0x430
[ 215.636255][ C0] hrtimer_interrupt+0x314/0x770
[ 215.636258][ C0] smp_apic_timer_interrupt+0x160/0x610
[ 215.636261][ C0] apic_timer_interrupt+0xf/0x20
[ 215.636264][ C0]
[ 215.636267][ C0] RIP: 0010:native_safe_halt+0xe/0x10
[ 215.636277][ C0] Code: a8 f4 59 fa eb 8a 90 90 90 90 90 90 e9 07 00 00 00 0f 00 2d 04 06 53 00 f4 c3 66 90 e9 07 00 00 00 0f 00 2d f4 05 53 00 fb f4 90 55 48 89 e5 41 57 41 56 41 55 41 54 53 e8 3e d4 0b fa e8 79
[ 215.636280][ C0] RSP: 0018:ffffffff88e07ce8 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
[ 215.636288][ C0] RAX: 1ffffffff11e643f RBX: ffffffff88e7a1c0 RCX: 0000000000000000
[ 215.636293][ C0] RDX: dffffc0000000000 RSI: 0000000000000006 RDI: ffffffff88e7aa5c
[ 215.636297][ C0] RBP: ffffffff88e07d18 R08: ffffffff88e7a1c0 R09: 0000000000000000
[ 215.636302][ C0] R10: 0000000000000000 R11: 0000000000000000 R12: dffffc0000000000
[ 215.636307][ C0] R13: ffffffff89c828c0 R14: 0000000000000000 R15: 0000000000000000
[ 215.636310][ C0] ? default_idle+0x4e/0x360
[ 215.636313][ C0] arch_cpu_idle+0xa/0x10
[ 215.636316][ C0] default_idle_call+0x84/0xb0
[ 215.636319][ C0] do_idle+0x3b7/0x6e0
[ 215.636322][ C0] ? arch_cpu_idle_exit+0x80/0x80
[ 215.636325][ C0] cpu_startup_entry+0x1b/0x20
[ 215.636328][ C0] rest_init+0x23b/0x371
[ 215.636331][ C0] arch_call_rest_init+0xe/0x1b
[ 215.636334][ C0] start_kernel+0x904/0x943
[ 215.636338][ C0] ? mem_encrypt_init+0xb/0xb
[ 215.636341][ C0] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20
[ 215.636344][ C0] ? x86_family+0x41/0x50
[ 215.636348][ C0] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20
[ 215.636352][ C0] x86_64_start_reservations+0x29/0x2b
[ 215.636355][ C0] x86_64_start_kernel+0x77/0x7b
[ 215.636358][ C0] secondary_startup_64+0xa4/0xb0
[ 215.636577][ T1077] Kernel panic - not syncing: hung_task: blocked tasks
[ 216.040686][ T1077] CPU: 1 PID: 1077 Comm: khungtaskd Not tainted 5.4.0-rc4-next-20191025 #0
[ 216.049263][ T1077] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 216.059318][ T1077] Call Trace:
[ 216.062618][ T1077] dump_stack+0x172/0x1f0
[ 216.067037][ T1077] panic+0x2e3/0x75c
[ 216.070996][ T1077] ? add_taint.cold+0x16/0x16
[ 216.075708][ T1077] ? __sanitizer_cov_trace_cmp4+0x16/0x20
[ 216.081424][ T1077] ? printk_safe_flush+0xf2/0x140
[ 216.086454][ T1077] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20
[ 216.092700][ T1077] ? nmi_trigger_cpumask_backtrace+0x224/0x28b
[ 216.098838][ T1077] ? nmi_trigger_cpumask_backtrace+0x21b/0x28b
[ 216.104988][ T1077] watchdog+0xca0/0x1350
[ 216.109249][ T1077] kthread+0x361/0x430
[ 216.113306][ T1077] ? reset_hung_task_detector+0x30/0x30
[ 216.118839][ T1077] ? kthread_mod_delayed_work+0x1f0/0x1f0
[ 216.124542][ T1077] ret_from_fork+0x24/0x30
[ 216.130670][ T1077] Kernel Offset: disabled
[ 216.135008][ T1077] Rebooting in 86400 seconds..