[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c.
[ 65.376601][ T23] audit: type=1800 audit(1572555038.051:25): pid=8963 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0
[ 65.397247][ T23] audit: type=1800 audit(1572555038.051:26): pid=8963 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0
[ 65.420275][ T23] audit: type=1800 audit(1572555038.051:27): pid=8963 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 '10.128.0.232' (ECDSA) to the list of known hosts.
syzkaller login: [ 245.146863][ T1078] INFO: task khugepaged:1085 blocked for more than 143 seconds.
[ 245.154763][ T1078] Not tainted 5.4.0-rc5-next-20191031 #0
[ 245.161759][ T1078] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 245.170636][ T1078] khugepaged D27840 1085 2 0x80004000
[ 245.177078][ T1078] Call Trace:
[ 245.180597][ T1078] __schedule+0x94a/0x1e70
[ 245.185019][ T1078] ? __sched_text_start+0x8/0x8
[ 245.190010][ T1078] ? blk_insert_cloned_request+0x530/0x530
[ 245.195843][ T1078] ? _raw_spin_unlock_irq+0x23/0x80
[ 245.201123][ T1078] ? __lock_page+0x3d9/0xab0
[ 245.205726][ T1078] ? _raw_spin_unlock_irq+0x23/0x80
[ 245.211230][ T1078] schedule+0xdc/0x2b0
[ 245.215346][ T1078] io_schedule+0x1c/0x70
[ 245.219816][ T1078] __lock_page+0x422/0xab0
[ 245.224380][ T1078] ? wait_on_page_bit+0xa60/0xa60
[ 245.229495][ T1078] ? page_cache_next_miss+0x340/0x340
[ 245.234891][ T1078] ? ___might_sleep+0x163/0x2c0
[ 245.239844][ T1078] ? __might_sleep+0x95/0x190
[ 245.244545][ T1078] mpage_prepare_extent_to_map+0xb3f/0xf90
[ 245.250430][ T1078] ? mpage_process_page_bufs+0x780/0x780
[ 245.256084][ T1078] ? rcu_read_lock_any_held.part.0+0x50/0x50
[ 245.262156][ T1078] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20
[ 245.269447][ T1078] ext4_writepages+0xb6a/0x2e70
[ 245.274424][ T1078] ? __this_cpu_preempt_check+0x2c/0x190
[ 245.280165][ T1078] ? ext4_mark_inode_dirty+0x9b0/0x9b0
[ 245.285632][ T1078] ? 0xffffffff81000000
[ 245.290607][ T1078] ? mark_lock+0xc2/0x1220
[ 245.295039][ T1078] ? prep_new_page+0x19f/0x200
[ 245.300075][ T1078] ? wbc_attach_and_unlock_inode+0x515/0x920
[ 245.306090][ T1078] ? find_held_lock+0x35/0x130
[ 245.311463][ T1078] ? wbc_attach_and_unlock_inode+0x515/0x920
[ 245.317542][ T1078] ? ext4_mark_inode_dirty+0x9b0/0x9b0
[ 245.323109][ T1078] do_writepages+0xfa/0x2a0
[ 245.327699][ T1078] ? do_writepages+0xfa/0x2a0
[ 245.333270][ T1078] ? lock_downgrade+0x920/0x920
[ 245.338398][ T1078] ? page_writeback_cpu_online+0x20/0x20
[ 245.344190][ T1078] ? __kasan_check_read+0x11/0x20
[ 245.349408][ T1078] ? do_raw_spin_unlock+0x57/0x270
[ 245.354535][ T1078] ? _raw_spin_unlock+0x28/0x40
[ 245.359468][ T1078] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20
[ 245.365849][ T1078] ? wbc_attach_and_unlock_inode+0x5bf/0x920
[ 245.371922][ T1078] __filemap_fdatawrite_range+0x2bc/0x3b0
[ 245.377772][ T1078] ? delete_from_page_cache_batch+0xfe0/0xfe0
[ 245.383862][ T1078] ? lockdep_hardirqs_on+0x421/0x5e0
[ 245.389238][ T1078] filemap_flush+0x24/0x30
[ 245.393688][ T1078] collapse_file+0x36b1/0x41a0
[ 245.398699][ T1078] ? khugepaged+0x21c0/0x4360
[ 245.403392][ T1078] ? trace_event_raw_event_mm_collapse_huge_page_isolate+0x370/0x370
[ 245.411532][ T1078] ? rcu_preempt_deferred_qs_irqrestore+0x4ff/0xd60
[ 245.419045][ T1078] ? __sanitizer_cov_trace_cmp4+0x16/0x20
[ 245.424894][ T1078] ? khugepaged_find_target_node+0x142/0x180
[ 245.430950][ T1078] khugepaged+0x2da9/0x4360
[ 245.435472][ T1078] ? __kasan_check_read+0x11/0x20
[ 245.440702][ T1078] ? __lock_acquire+0x16f2/0x4a00
[ 245.446396][ T1078] ? _raw_spin_unlock_irq+0x23/0x80
[ 245.451671][ T1078] ? finish_task_switch+0x147/0x750
[ 245.456949][ T1078] ? _raw_spin_unlock_irq+0x23/0x80
[ 245.462162][ T1078] ? lockdep_hardirqs_on+0x421/0x5e0
[ 245.467516][ T1078] ? collapse_pte_mapped_thp+0xbe0/0xbe0
[ 245.473285][ T1078] ? lock_downgrade+0x920/0x920
[ 245.478223][ T1078] ? finish_wait+0x260/0x260
[ 245.482825][ T1078] ? lockdep_hardirqs_on+0x421/0x5e0
[ 245.488188][ T1078] ? trace_hardirqs_on+0x67/0x240
[ 245.493230][ T1078] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20
[ 245.499669][ T1078] ? __kthread_parkme+0x108/0x1c0
[ 245.504796][ T1078] ? __kasan_check_read+0x11/0x20
[ 245.511371][ T1078] kthread+0x361/0x430
[ 245.515448][ T1078] ? collapse_pte_mapped_thp+0xbe0/0xbe0
[ 245.521171][ T1078] ? kthread_mod_delayed_work+0x1f0/0x1f0
[ 245.526954][ T1078] ret_from_fork+0x24/0x30
[ 245.531569][ T1078]
[ 245.531569][ T1078] Showing all locks held in the system:
[ 245.539392][ T1078] 4 locks held by kworker/u4:5/744:
[ 245.544712][ T1078] #0: ffff8880a7c2e128 ((wq_completion)writeback){+.+.}, at: process_one_work+0x88b/0x1740
[ 245.555608][ T1078] #1: ffff8880a8107dc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0x8c1/0x1740
[ 245.566997][ T1078] #2: ffff88821598a0d8 (&type->s_umount_key#32){++++}, at: trylock_super+0x22/0x110
[ 245.576508][ T1078] #3: ffff88821598c990 (&sbi->s_journal_flag_rwsem){.+.+}, at: do_writepages+0xfa/0x2a0
[ 245.586443][ T1078] 1 lock held by khungtaskd/1078:
[ 245.591527][ T1078] #0: ffffffff88faba40 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x279
[ 245.600893][ T1078] 1 lock held by khugepaged/1085:
[ 245.606263][ T1078] #0: ffff88821598c990 (&sbi->s_journal_flag_rwsem){.+.+}, at: do_writepages+0xfa/0x2a0
[ 245.616718][ T1078] 2 locks held by rsyslogd/9001:
[ 245.621652][ T1078] #0: ffff8880a4429120 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110
[ 245.630357][ T1078] #1: ffffffff88fa0f78 (logbuf_lock){-.-.}, at: is_bpf_text_address+0x0/0x160
[ 245.639389][ T1078] 2 locks held by getty/9091:
[ 245.644053][ T1078] #0: ffff888096311090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40
[ 245.653078][ T1078] #1: ffffc90005f2d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0
[ 245.662809][ T1078] 2 locks held by getty/9092:
[ 245.667545][ T1078] #0: ffff8880a4a2d090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40
[ 245.676528][ T1078] #1: ffffc90005f312e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0
[ 245.687132][ T1078] 2 locks held by getty/9093:
[ 245.691814][ T1078] #0: ffff888094518090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40
[ 245.701080][ T1078] #1: ffffc90005f392e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0
[ 245.710955][ T1078] 2 locks held by getty/9094:
[ 245.715763][ T1078] #0: ffff888091752090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40
[ 245.724804][ T1078] #1: ffffc90005f292e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0
[ 245.734490][ T1078] 2 locks held by getty/9095:
[ 245.739289][ T1078] #0: ffff8880a4702090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40
[ 245.748546][ T1078] #1: ffffc90005f112e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0
[ 245.758471][ T1078] 2 locks held by getty/9096:
[ 245.763272][ T1078] #0: ffff8880a4d79090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40
[ 245.772771][ T1078] #1: ffffc90005f352e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0
[ 245.782548][ T1078] 2 locks held by getty/9097:
[ 245.787284][ T1078] #0: ffff88809387b090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40
[ 245.796372][ T1078] #1: ffffc90005f092e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0
[ 245.806088][ T1078] 1 lock held by syz-execprog/9115:
[ 245.811582][ T1078] #0: ffff8880a66bf428 (&ei->i_mmap_sem){++++}, at: ext4_filemap_fault+0x7e/0xb2
[ 245.821830][ T1078]
[ 245.824181][ T1078] =============================================
[ 245.824181][ T1078]
[ 245.832709][ T1078] NMI backtrace for cpu 1
[ 245.837102][ T1078] CPU: 1 PID: 1078 Comm: khungtaskd Not tainted 5.4.0-rc5-next-20191031 #0
[ 245.845704][ T1078] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 245.855770][ T1078] Call Trace:
[ 245.859136][ T1078] dump_stack+0x172/0x1f0
[ 245.863474][ T1078] nmi_cpu_backtrace.cold+0x70/0xb2
[ 245.868749][ T1078] ? vprintk_func+0x86/0x189
[ 245.873350][ T1078] ? lapic_can_unplug_cpu.cold+0x3a/0x3a
[ 245.879093][ T1078] nmi_trigger_cpumask_backtrace+0x23b/0x28b
[ 245.885080][ T1078] arch_trigger_cpumask_backtrace+0x14/0x20
[ 245.891204][ T1078] watchdog+0xc8f/0x1350
[ 245.895583][ T1078] kthread+0x361/0x430
[ 245.899754][ T1078] ? reset_hung_task_detector+0x30/0x30
[ 245.905316][ T1078] ? kthread_mod_delayed_work+0x1f0/0x1f0
[ 245.911047][ T1078] ret_from_fork+0x24/0x30
[ 245.915568][ T1078] Sending NMI from CPU 1 to CPUs 0:
[ 245.921385][ C0] NMI backtrace for cpu 0
[ 245.921391][ C0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.4.0-rc5-next-20191031 #0
[ 245.921397][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 245.921401][ C0] RIP: 0010:update_dl_rq_load_avg+0x4f1/0xa60
[ 245.921411][ C0] Code: 8b 54 24 30 83 c2 03 40 38 f2 7c 09 40 84 f6 0f 85 0c 04 00 00 4d 85 ff 44 89 ab 5c 0b 00 00 0f 84 6a fc ff ff e9 3b fc ff ff <45> 31 d2 45 31 e4 e9 35 fe ff ff 65 44 8b 25 4c 25 aa 7e 41 83 fc
[ 245.921415][ C0] RSP: 0018:ffff8880ae809cd0 EFLAGS: 00000012
[ 245.921422][ C0] RAX: 0000000000000ea8 RBX: ffff8880ae834d40 RCX: 0000000000000000
[ 245.921426][ C0] RDX: 0000000000000007 RSI: ffff8880ae834d40 RDI: ffff8880ae835880
[ 245.921431][ C0] RBP: ffff8880ae809d48 R08: 0000000000000004 R09: 00000000000001ca
[ 245.921435][ C0] R10: ffffed1015d06b7c R11: ffff8880ae835be3 R12: 0000000000000000
[ 245.921440][ C0] R13: 0000000000001072 R14: ffff8880ae83589c R15: 0000000000000000
[ 245.921445][ C0] FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
[ 245.921448][ C0] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 245.921453][ C0] CR2: 000000c420000240 CR3: 00000000a4298000 CR4: 00000000001406f0
[ 245.921457][ C0] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 245.921462][ C0] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 245.921464][ C0] Call Trace:
[ 245.921467][ C0]
[ 245.921470][ C0] update_blocked_averages+0xbd8/0x1750
[ 245.921473][ C0] ? lock_acquire+0x190/0x410
[ 245.921477][ C0] _nohz_idle_balance+0x2e8/0x3f0
[ 245.921480][ C0] run_rebalance_domains+0x1c6/0x2d0
[ 245.921483][ C0] __do_softirq+0x262/0x98c
[ 245.921486][ C0] ? sched_clock_cpu+0x1b/0x1b0
[ 245.921489][ C0] irq_exit+0x19b/0x1e0
[ 245.921492][ C0] scheduler_ipi+0x38c/0x610
[ 245.921496][ C0] ? trace_hardirqs_off_thunk+0x1a/0x1c
[ 245.921499][ C0] smp_reschedule_interrupt+0x78/0x4c0
[ 245.921502][ C0] reschedule_interrupt+0xf/0x20
[ 245.921505][ C0]
[ 245.921508][ C0] RIP: 0010:native_safe_halt+0xe/0x10
[ 245.921517][ C0] Code: d8 b6 58 fa eb 8a 90 90 90 90 90 90 e9 07 00 00 00 0f 00 2d 24 cc 51 00 f4 c3 66 90 e9 07 00 00 00 0f 00 2d 14 cc 51 00 fb f4 90 55 48 89 e5 41 57 41 56 41 55 41 54 53 e8 8e 95 0a fa e8 39
[ 245.921521][ C0] RSP: 0018:ffffffff88e07ce8 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff02
[ 245.921529][ C0] RAX: 1ffffffff11e643f RBX: ffffffff88e7a1c0 RCX: 0000000000000000
[ 245.921533][ C0] RDX: dffffc0000000000 RSI: 0000000000000006 RDI: ffffffff88e7aa5c
[ 245.921537][ C0] RBP: ffffffff88e07d18 R08: ffffffff88e7a1c0 R09: 0000000000000000
[ 245.921542][ C0] R10: 0000000000000000 R11: 0000000000000000 R12: dffffc0000000000
[ 245.921546][ C0] R13: ffffffff89c81e80 R14: 0000000000000000 R15: 0000000000000000
[ 245.921549][ C0] ? default_idle+0x4e/0x360
[ 245.921552][ C0] arch_cpu_idle+0xa/0x10
[ 245.921555][ C0] default_idle_call+0x84/0xb0
[ 245.921558][ C0] do_idle+0x3b7/0x6e0
[ 245.921561][ C0] ? arch_cpu_idle_exit+0x80/0x80
[ 245.921565][ C0] ? trace_hardirqs_on+0x67/0x240
[ 245.921568][ C0] ? __kasan_check_read+0x11/0x20
[ 245.921572][ C0] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20
[ 245.921575][ C0] ? debug_smp_processor_id+0x33/0x18a
[ 245.921578][ C0] cpu_startup_entry+0x1b/0x20
[ 245.921581][ C0] rest_init+0x23b/0x371
[ 245.921584][ C0] arch_call_rest_init+0xe/0x1b
[ 245.921587][ C0] start_kernel+0x904/0x943
[ 245.921590][ C0] ? mem_encrypt_init+0xb/0xb
[ 245.921594][ C0] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20
[ 245.921597][ C0] ? x86_family+0x41/0x50
[ 245.921601][ C0] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20
[ 245.921604][ C0] x86_64_start_reservations+0x29/0x2b
[ 245.921607][ C0] x86_64_start_kernel+0x77/0x7b
[ 245.921611][ C0] secondary_startup_64+0xa4/0xb0
[ 245.921863][ T1078] Kernel panic - not syncing: hung_task: blocked tasks
[ 246.301593][ T1078] CPU: 1 PID: 1078 Comm: khungtaskd Not tainted 5.4.0-rc5-next-20191031 #0
[ 246.310259][ T1078] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 246.320307][ T1078] Call Trace:
[ 246.323614][ T1078] dump_stack+0x172/0x1f0
[ 246.327951][ T1078] panic+0x2e3/0x75c
[ 246.331840][ T1078] ? add_taint.cold+0x16/0x16
[ 246.336512][ T1078] ? __sanitizer_cov_trace_cmp4+0x16/0x20
[ 246.342236][ T1078] ? printk_safe_flush+0xf2/0x140
[ 246.347254][ T1078] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20
[ 246.353492][ T1078] ? nmi_trigger_cpumask_backtrace+0x224/0x28b
[ 246.359651][ T1078] ? nmi_trigger_cpumask_backtrace+0x21b/0x28b
[ 246.365848][ T1078] watchdog+0xca0/0x1350
[ 246.370122][ T1078] kthread+0x361/0x430
[ 246.374199][ T1078] ? reset_hung_task_detector+0x30/0x30
[ 246.379749][ T1078] ? kthread_mod_delayed_work+0x1f0/0x1f0
[ 246.385477][ T1078] ret_from_fork+0x24/0x30
[ 246.391701][ T1078] Kernel Offset: disabled
[ 246.396055][ T1078] Rebooting in 86400 seconds..