[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 56.082130][ T26] audit: type=1800 audit(1572142437.407:25): pid=8528 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 56.116656][ T26] audit: type=1800 audit(1572142437.407:26): pid=8528 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 56.139040][ T26] audit: type=1800 audit(1572142437.417:27): pid=8528 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[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.10.63' (ECDSA) to the list of known hosts. syzkaller login: [ 277.206817][ T1081] INFO: task khugepaged:1088 blocked for more than 143 seconds. [ 277.214958][ T1081] Not tainted 5.4.0-rc4-next-20191025 #0 [ 277.221281][ T1081] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 277.230122][ T1081] khugepaged D27448 1088 2 0x80004000 [ 277.236464][ T1081] Call Trace: [ 277.239884][ T1081] __schedule+0x94a/0x1e70 [ 277.244396][ T1081] ? __sched_text_start+0x8/0x8 [ 277.249324][ T1081] ? blk_insert_cloned_request+0x530/0x530 [ 277.255227][ T1081] ? _raw_spin_unlock_irq+0x23/0x80 [ 277.260530][ T1081] ? __lock_page+0x3d9/0xab0 [ 277.265155][ T1081] ? _raw_spin_unlock_irq+0x23/0x80 [ 277.270418][ T1081] schedule+0xdc/0x2b0 [ 277.274535][ T1081] io_schedule+0x1c/0x70 [ 277.278846][ T1081] __lock_page+0x422/0xab0 [ 277.283277][ T1081] ? wait_on_page_bit+0xa60/0xa60 [ 277.288373][ T1081] ? page_cache_next_miss+0x340/0x340 [ 277.293771][ T1081] ? ___might_sleep+0x163/0x2c0 [ 277.298712][ T1081] ? __might_sleep+0x95/0x190 [ 277.303402][ T1081] mpage_prepare_extent_to_map+0xb3f/0xf90 [ 277.309288][ T1081] ? mpage_process_page_bufs+0x780/0x780 [ 277.314994][ T1081] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 277.321049][ T1081] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 277.327357][ T1081] ext4_writepages+0xb6a/0x2e70 [ 277.332208][ T1081] ? get_page_from_freelist+0x21fb/0x4330 [ 277.338010][ T1081] ? find_held_lock+0x35/0x130 [ 277.342800][ T1081] ? get_page_from_freelist+0x21fb/0x4330 [ 277.348587][ T1081] ? ext4_mark_inode_dirty+0x9b0/0x9b0 [ 277.354058][ T1081] ? 0xffffffff81000000 [ 277.358279][ T1081] ? mark_lock+0xc2/0x1220 [ 277.362708][ T1081] ? prep_new_page+0x19f/0x200 [ 277.367525][ T1081] ? wbc_attach_and_unlock_inode+0x515/0x920 [ 277.373563][ T1081] ? find_held_lock+0x35/0x130 [ 277.378399][ T1081] ? wbc_attach_and_unlock_inode+0x515/0x920 [ 277.384392][ T1081] ? ext4_mark_inode_dirty+0x9b0/0x9b0 [ 277.389912][ T1081] do_writepages+0xfa/0x2a0 [ 277.394432][ T1081] ? do_writepages+0xfa/0x2a0 [ 277.399282][ T1081] ? lock_downgrade+0x920/0x920 [ 277.404156][ T1081] ? page_writeback_cpu_online+0x20/0x20 [ 277.409857][ T1081] ? __kasan_check_read+0x11/0x20 [ 277.414895][ T1081] ? do_raw_spin_unlock+0x57/0x270 [ 277.420067][ T1081] ? _raw_spin_unlock+0x28/0x40 [ 277.424933][ T1081] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 277.431241][ T1081] ? wbc_attach_and_unlock_inode+0x5bf/0x920 [ 277.437286][ T1081] __filemap_fdatawrite_range+0x2bc/0x3b0 [ 277.443009][ T1081] ? delete_from_page_cache_batch+0xfe0/0xfe0 [ 277.449132][ T1081] ? lockdep_hardirqs_on+0x421/0x5e0 [ 277.454433][ T1081] filemap_flush+0x24/0x30 [ 277.459061][ T1081] collapse_file+0x36b1/0x41a0 [ 277.463837][ T1081] ? rcu_lockdep_current_cpu_online+0xe3/0x130 [ 277.470058][ T1081] ? khugepaged+0x21d0/0x4360 [ 277.474752][ T1081] ? trace_event_raw_event_mm_collapse_huge_page_isolate+0x370/0x370 [ 277.482920][ T1081] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 277.488844][ T1081] ? khugepaged_find_target_node+0x142/0x180 [ 277.494848][ T1081] khugepaged+0x2da9/0x4360 [ 277.499441][ T1081] ? __kasan_check_read+0x11/0x20 [ 277.504508][ T1081] ? __lock_acquire+0x16f2/0x4a00 [ 277.509603][ T1081] ? _raw_spin_unlock_irq+0x23/0x80 [ 277.514826][ T1081] ? finish_task_switch+0x147/0x750 [ 277.520104][ T1081] ? _raw_spin_unlock_irq+0x23/0x80 [ 277.525325][ T1081] ? lockdep_hardirqs_on+0x421/0x5e0 [ 277.530681][ T1081] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 277.536322][ T1081] ? lock_downgrade+0x920/0x920 [ 277.541226][ T1081] ? finish_wait+0x260/0x260 [ 277.545831][ T1081] ? lockdep_hardirqs_on+0x421/0x5e0 [ 277.551182][ T1081] ? trace_hardirqs_on+0x67/0x240 [ 277.556230][ T1081] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 277.562534][ T1081] ? __kthread_parkme+0x108/0x1c0 [ 277.567607][ T1081] ? __kasan_check_read+0x11/0x20 [ 277.572635][ T1081] kthread+0x361/0x430 [ 277.576761][ T1081] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 277.582406][ T1081] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 277.588182][ T1081] ret_from_fork+0x24/0x30 [ 277.592698][ T1081] [ 277.592698][ T1081] Showing all locks held in the system: [ 277.600484][ T1081] 4 locks held by kworker/u4:3/423: [ 277.605680][ T1081] #0: ffff8880a8d13528 ((wq_completion)writeback){+.+.}, at: process_one_work+0x88b/0x1740 [ 277.616093][ T1081] #1: ffff8880a8807dc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0x8c1/0x1740 [ 277.627453][ T1081] #2: ffff88809b0700d8 (&type->s_umount_key#32){++++}, at: trylock_super+0x22/0x110 [ 277.636979][ T1081] #3: ffff88809b072990 (&sbi->s_journal_flag_rwsem){.+.+}, at: do_writepages+0xfa/0x2a0 [ 277.646841][ T1081] 1 lock held by khungtaskd/1081: [ 277.651865][ T1081] #0: ffffffff88faba80 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x279 [ 277.661223][ T1081] 1 lock held by khugepaged/1088: [ 277.666253][ T1081] #0: ffff88809b072990 (&sbi->s_journal_flag_rwsem){.+.+}, at: do_writepages+0xfa/0x2a0 [ 277.676185][ T1081] 4 locks held by rsyslogd/8566: [ 277.681171][ T1081] #0: ffff8880a4018860 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 [ 277.689826][ T1081] #1: ffffffff89047ec0 (fs_reclaim){+.+.}, at: do_syslog+0x699/0x1870 [ 277.698141][ T1081] #2: ffffffff88faba80 (rcu_read_lock){....}, at: update_curr+0x2ea/0x8d0 [ 277.706796][ T1081] #3: ffffffff88faba80 (rcu_read_lock){....}, at: update_curr+0x2ea/0x8d0 [ 277.715416][ T1081] 2 locks held by getty/8656: [ 277.720138][ T1081] #0: ffff888095888090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 277.729148][ T1081] #1: ffffc90005f292e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 277.738860][ T1081] 2 locks held by getty/8657: [ 277.743540][ T1081] #0: ffff8880a0d2a090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 277.752536][ T1081] #1: ffffc90005f3b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 277.762137][ T1081] 2 locks held by getty/8658: [ 277.766846][ T1081] #0: ffff8880934ae090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 277.775792][ T1081] #1: ffffc90005f372e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 277.785408][ T1081] 2 locks held by getty/8659: [ 277.790167][ T1081] #0: ffff8880a14c8090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 277.799166][ T1081] #1: ffffc90005f152e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 277.808792][ T1081] 2 locks held by getty/8660: [ 277.813465][ T1081] #0: ffff888095c70090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 277.822471][ T1081] #1: ffffc90005f1d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 277.832116][ T1081] 2 locks held by getty/8661: [ 277.836838][ T1081] #0: ffff8880985f9090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 277.845804][ T1081] #1: ffffc90005f332e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 277.855566][ T1081] 2 locks held by getty/8662: [ 277.860284][ T1081] #0: ffff88809a8ab090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 277.869290][ T1081] #1: ffffc90005f092e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 277.878998][ T1081] 1 lock held by syz-execprog/8683: [ 277.884189][ T1081] #0: ffff8880a33fa3e8 (&ei->i_mmap_sem){++++}, at: ext4_filemap_fault+0x7e/0xb2 [ 277.893481][ T1081] [ 277.895815][ T1081] ============================================= [ 277.895815][ T1081] [ 277.904271][ T1081] NMI backtrace for cpu 0 [ 277.908664][ T1081] CPU: 0 PID: 1081 Comm: khungtaskd Not tainted 5.4.0-rc4-next-20191025 #0 [ 277.917229][ T1081] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 277.927284][ T1081] Call Trace: [ 277.930588][ T1081] dump_stack+0x172/0x1f0 [ 277.934910][ T1081] nmi_cpu_backtrace.cold+0x70/0xb2 [ 277.940103][ T1081] ? vprintk_func+0x86/0x189 [ 277.944684][ T1081] ? lapic_can_unplug_cpu.cold+0x3a/0x3a [ 277.950303][ T1081] nmi_trigger_cpumask_backtrace+0x23b/0x28b [ 277.956296][ T1081] arch_trigger_cpumask_backtrace+0x14/0x20 [ 277.962179][ T1081] watchdog+0xc8f/0x1350 [ 277.966432][ T1081] kthread+0x361/0x430 [ 277.970496][ T1081] ? reset_hung_task_detector+0x30/0x30 [ 277.976036][ T1081] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 277.981761][ T1081] ret_from_fork+0x24/0x30 [ 277.986242][ T1081] Sending NMI from CPU 0 to CPUs 1: [ 277.992346][ C1] NMI backtrace for cpu 1 [ 277.992351][ C1] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.4.0-rc4-next-20191025 #0 [ 277.992357][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 277.992360][ C1] RIP: 0010:match_held_lock+0xb/0x510 [ 277.992371][ C1] Code: e8 ba fa ff ff 85 c0 78 02 c9 c3 89 c7 89 45 fc e8 8a e6 ff ff 8b 45 fc c9 c3 0f 1f 44 00 00 48 b8 00 00 00 00 00 fc ff df 55 <48> 89 e5 41 57 41 56 41 55 41 54 53 48 89 fb 48 83 c7 10 48 89 fa [ 277.992374][ C1] RSP: 0018:ffff8880ae909958 EFLAGS: 00000002 [ 277.992382][ C1] RAX: dffffc0000000000 RBX: ffff8880a98ba340 RCX: ffff8880a98babe0 [ 277.992386][ C1] RDX: 1ffff1101531757b RSI: ffff8880ae934d58 RDI: ffff8880a98babe0 [ 277.992391][ C1] RBP: ffff8880ae9099b0 R08: 1ffffffff11f2240 R09: fffffbfff11f2241 [ 277.992396][ C1] R10: fffffbfff11f2240 R11: ffffffff88f91207 R12: ffffed101531757b [ 277.992401][ C1] R13: ffff8880a98babe0 R14: ffff8880ae934d58 R15: 0000000000000000 [ 277.992406][ C1] FS: 0000000000000000(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 [ 277.992410][ C1] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 277.992415][ C1] CR2: ffffffffff600400 CR3: 00000000953e6000 CR4: 00000000001406e0 [ 277.992419][ C1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 277.992424][ C1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 277.992426][ C1] Call Trace: [ 277.992429][ C1] [ 277.992432][ C1] ? lock_is_held_type+0x1b8/0x320 [ 277.992435][ C1] update_curr+0x296/0x8d0 [ 277.992438][ C1] ? record_times+0x1e/0x2b0 [ 277.992442][ C1] enqueue_entity+0x31b/0x17b0 [ 277.992445][ C1] ? psi_task_change+0x4f2/0x9d0 [ 277.992448][ C1] enqueue_task_fair+0x1a7/0x1260 [ 277.992451][ C1] activate_task+0x110/0x490 [ 277.992454][ C1] ttwu_do_activate+0xd0/0x130 [ 277.992458][ C1] try_to_wake_up+0xb23/0x1ab0 [ 277.992461][ C1] ? migrate_swap_stop+0x9f0/0x9f0 [ 277.992465][ C1] ? rcu_read_lock_sched_held+0x9c/0xd0 [ 277.992468][ C1] wake_up_process+0x10/0x20 [ 277.992471][ C1] hrtimer_wakeup+0x48/0x60 [ 277.992475][ C1] __hrtimer_run_queues+0x364/0xe40 [ 277.992478][ C1] ? hrtimer_init_sleeper_on_stack+0xa0/0xa0 [ 277.992481][ C1] ? hrtimer_init+0x330/0x330 [ 277.992486][ C1] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 277.992490][ C1] ? ktime_get_update_offsets_now+0x2ce/0x430 [ 277.992493][ C1] hrtimer_interrupt+0x314/0x770 [ 277.992496][ C1] smp_apic_timer_interrupt+0x160/0x610 [ 277.992500][ C1] apic_timer_interrupt+0xf/0x20 [ 277.992503][ C1] RIP: 0010:__do_softirq+0x227/0x98c [ 277.992512][ C1] Code: c7 c0 f0 21 f3 88 48 c1 e8 03 42 80 3c 30 00 0f 85 b1 06 00 00 48 83 3d d6 1f 73 01 00 0f 84 d6 05 00 00 fb 66 0f 1f 44 00 00 ff ff ff ff 48 c7 45 c8 00 91 e0 88 0f bc 45 d4 83 c0 01 89 45 [ 277.992516][ C1] RSP: 0018:ffff8880ae909ee8 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 [ 277.992524][ C1] RAX: 1ffffffff11e643e RBX: ffff8880a98ba340 RCX: 0000000000000000 [ 277.992529][ C1] RDX: 0000000000000000 RSI: 0000000000000002 RDI: ffff8880a98babdc [ 277.992533][ C1] RBP: ffff8880ae909f68 R08: ffff8880a98ba340 R09: 0000000000000000 [ 277.992538][ C1] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880a98ba340 [ 277.992542][ C1] R13: ffffffff88be5148 R14: dffffc0000000000 R15: 0000000000000001 [ 277.992546][ C1] ? apic_timer_interrupt+0xa/0x20 [ 277.992549][ C1] ? __do_softirq+0x1fc/0x98c [ 277.992552][ C1] ? sched_clock_cpu+0x1b/0x1b0 [ 277.992556][ C1] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 277.992560][ C1] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 277.992563][ C1] ? __this_cpu_preempt_check+0x35/0x190 [ 277.992566][ C1] irq_exit+0x19b/0x1e0 [ 277.992569][ C1] scheduler_ipi+0x38c/0x610 [ 277.992573][ C1] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 277.992576][ C1] smp_reschedule_interrupt+0x78/0x4c0 [ 277.992579][ C1] reschedule_interrupt+0xf/0x20 [ 277.992582][ C1] [ 277.992585][ C1] RIP: 0010:native_safe_halt+0xe/0x10 [ 277.992594][ C1] 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 [ 277.992597][ C1] RSP: 0018:ffff8880a98cfd68 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff02 [ 277.992604][ C1] RAX: 1ffffffff11e643f RBX: ffff8880a98ba340 RCX: 0000000000000000 [ 277.992609][ C1] RDX: dffffc0000000000 RSI: 0000000000000006 RDI: ffff8880a98babdc [ 277.992613][ C1] RBP: ffff8880a98cfd98 R08: ffff8880a98ba340 R09: 0000000000000000 [ 277.992617][ C1] R10: 0000000000000000 R11: 0000000000000000 R12: dffffc0000000000 [ 277.992621][ C1] R13: ffffffff89c828c0 R14: 0000000000000000 R15: 0000000000000001 [ 277.992624][ C1] ? default_idle+0x4e/0x360 [ 277.992627][ C1] arch_cpu_idle+0xa/0x10 [ 277.992630][ C1] default_idle_call+0x84/0xb0 [ 277.992633][ C1] do_idle+0x3b7/0x6e0 [ 277.992636][ C1] ? arch_cpu_idle_exit+0x80/0x80 [ 277.992639][ C1] ? _raw_spin_unlock_irqrestore+0x9f/0xe0 [ 277.992642][ C1] ? complete+0x61/0x80 [ 277.992645][ C1] cpu_startup_entry+0x1b/0x20 [ 277.992648][ C1] start_secondary+0x2f4/0x410 [ 277.992651][ C1] ? set_cpu_sibling_map+0x2180/0x2180 [ 277.992654][ C1] secondary_startup_64+0xa4/0xb0 [ 277.992670][ T1081] Kernel panic - not syncing: hung_task: blocked tasks [ 278.504059][ T1081] CPU: 0 PID: 1081 Comm: khungtaskd Not tainted 5.4.0-rc4-next-20191025 #0 [ 278.512637][ T1081] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 278.522686][ T1081] Call Trace: [ 278.525981][ T1081] dump_stack+0x172/0x1f0 [ 278.530307][ T1081] panic+0x2e3/0x75c [ 278.534197][ T1081] ? add_taint.cold+0x16/0x16 [ 278.538867][ T1081] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 278.544585][ T1081] ? printk_safe_flush+0xf2/0x140 [ 278.549601][ T1081] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 278.555908][ T1081] ? nmi_trigger_cpumask_backtrace+0x224/0x28b [ 278.562061][ T1081] ? nmi_trigger_cpumask_backtrace+0x21b/0x28b [ 278.568219][ T1081] watchdog+0xca0/0x1350 [ 278.572455][ T1081] kthread+0x361/0x430 [ 278.576521][ T1081] ? reset_hung_task_detector+0x30/0x30 [ 278.582068][ T1081] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 278.587892][ T1081] ret_from_fork+0x24/0x30 [ 278.593800][ T1081] Kernel Offset: disabled [ 278.598160][ T1081] Rebooting in 86400 seconds..