[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 57.068184][ T26] audit: type=1800 audit(1571957045.191:25): pid=8585 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 57.087861][ T26] audit: type=1800 audit(1571957045.191:26): pid=8585 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 57.115003][ T26] audit: type=1800 audit(1571957045.201:27): pid=8585 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 '10.128.0.101' (ECDSA) to the list of known hosts. syzkaller login: [ 216.324912][ T1077] INFO: task khugepaged:1084 blocked for more than 143 seconds. [ 216.332839][ T1077] Not tainted 5.4.0-rc4-next-20191024 #0 [ 216.339198][ T1077] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 216.347917][ T1077] khugepaged D27568 1084 2 0x80004000 [ 216.354484][ T1077] Call Trace: [ 216.357839][ T1077] __schedule+0x94a/0x1e70 [ 216.362456][ T1077] ? __sched_text_start+0x8/0x8 [ 216.367392][ T1077] ? blk_insert_cloned_request+0x530/0x530 [ 216.373261][ T1077] ? _raw_spin_unlock_irq+0x23/0x80 [ 216.378510][ T1077] ? __lock_page+0x3d9/0xab0 [ 216.383109][ T1077] ? _raw_spin_unlock_irq+0x23/0x80 [ 216.388392][ T1077] schedule+0xd9/0x260 [ 216.392588][ T1077] io_schedule+0x1c/0x70 [ 216.396891][ T1077] __lock_page+0x422/0xab0 [ 216.401515][ T1077] ? wait_on_page_bit+0xa60/0xa60 [ 216.406765][ T1077] ? page_cache_next_miss+0x340/0x340 [ 216.412340][ T1077] ? ___might_sleep+0x163/0x2c0 [ 216.418012][ T1077] ? __might_sleep+0x95/0x190 [ 216.422716][ T1077] mpage_prepare_extent_to_map+0xb3f/0xf90 [ 216.428620][ T1077] ? mpage_process_page_bufs+0x780/0x780 [ 216.434426][ T1077] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 216.440677][ T1077] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 216.447092][ T1077] ext4_writepages+0xb6a/0x2e70 [ 216.451974][ T1077] ? get_page_from_freelist+0x21fb/0x4330 [ 216.457801][ T1077] ? find_held_lock+0x35/0x130 [ 216.462589][ T1077] ? get_page_from_freelist+0x21fb/0x4330 [ 216.468590][ T1077] ? ext4_mark_inode_dirty+0x9b0/0x9b0 [ 216.474065][ T1077] ? 0xffffffff81000000 [ 216.478281][ T1077] ? mark_lock+0xc2/0x1220 [ 216.482711][ T1077] ? prep_new_page+0x19f/0x200 [ 216.487931][ T1077] ? wbc_attach_and_unlock_inode+0x515/0x920 [ 216.494110][ T1077] ? find_held_lock+0x35/0x130 [ 216.498967][ T1077] ? wbc_attach_and_unlock_inode+0x515/0x920 [ 216.505230][ T1077] ? ext4_mark_inode_dirty+0x9b0/0x9b0 [ 216.510809][ T1077] do_writepages+0xfa/0x2a0 [ 216.518384][ T1077] ? do_writepages+0xfa/0x2a0 [ 216.523635][ T1077] ? lock_downgrade+0x920/0x920 [ 216.528604][ T1077] ? page_writeback_cpu_online+0x20/0x20 [ 216.534341][ T1077] ? __kasan_check_read+0x11/0x20 [ 216.539418][ T1077] ? do_raw_spin_unlock+0x57/0x270 [ 216.544556][ T1077] ? _raw_spin_unlock+0x28/0x40 [ 216.550441][ T1077] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 216.557045][ T1077] ? wbc_attach_and_unlock_inode+0x5bf/0x920 [ 216.563053][ T1077] __filemap_fdatawrite_range+0x2bc/0x3b0 [ 216.569158][ T1077] ? delete_from_page_cache_batch+0xfe0/0xfe0 [ 216.575521][ T1077] ? lockdep_hardirqs_on+0x421/0x5e0 [ 216.581099][ T1077] filemap_flush+0x24/0x30 [ 216.585638][ T1077] collapse_file+0x36b1/0x41a0 [ 216.590428][ T1077] ? khugepaged+0x2250/0x4360 [ 216.595266][ T1077] ? trace_event_raw_event_mm_collapse_huge_page_isolate+0x370/0x370 [ 216.603673][ T1077] ? rcu_preempt_deferred_qs_irqrestore+0x4ff/0xd60 [ 216.610371][ T1077] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 216.616167][ T1077] ? khugepaged_find_target_node+0x142/0x180 [ 216.622163][ T1077] khugepaged+0x2da9/0x4360 [ 216.626747][ T1077] ? __kasan_check_read+0x11/0x20 [ 216.631783][ T1077] ? __lock_acquire+0x16f2/0x4a00 [ 216.636868][ T1077] ? _raw_spin_unlock_irq+0x23/0x80 [ 216.642324][ T1077] ? finish_task_switch+0x147/0x750 [ 216.647599][ T1077] ? _raw_spin_unlock_irq+0x23/0x80 [ 216.652815][ T1077] ? lockdep_hardirqs_on+0x421/0x5e0 [ 216.658190][ T1077] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 216.663842][ T1077] ? lock_downgrade+0x920/0x920 [ 216.668777][ T1077] ? finish_wait+0x260/0x260 [ 216.673390][ T1077] ? lockdep_hardirqs_on+0x421/0x5e0 [ 216.679498][ T1077] ? trace_hardirqs_on+0x67/0x240 [ 216.684545][ T1077] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 216.690857][ T1077] ? __kthread_parkme+0x108/0x1c0 [ 216.695934][ T1077] ? __kasan_check_read+0x11/0x20 [ 216.701149][ T1077] kthread+0x361/0x430 [ 216.705323][ T1077] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 216.710966][ T1077] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 216.716743][ T1077] ret_from_fork+0x24/0x30 [ 216.721426][ T1077] [ 216.721426][ T1077] Showing all locks held in the system: [ 216.729214][ T1077] 4 locks held by kworker/u4:0/7: [ 216.734240][ T1077] #0: ffff8880a8284d28 ((wq_completion)writeback){+.+.}, at: process_one_work+0x88b/0x1740 [ 216.744379][ T1077] #1: ffff8880a988fdc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0x8c1/0x1740 [ 216.756022][ T1077] #2: ffff88809b03a0d8 (&type->s_umount_key#32){++++}, at: trylock_super+0x22/0x110 [ 216.765557][ T1077] #3: ffff88809b03c990 (&sbi->s_journal_flag_rwsem){.+.+}, at: do_writepages+0xfa/0x2a0 [ 216.775551][ T1077] 1 lock held by khungtaskd/1077: [ 216.780571][ T1077] #0: ffffffff88faba80 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x279 [ 216.789925][ T1077] 1 lock held by khugepaged/1084: [ 216.795008][ T1077] #0: ffff88809b03c990 (&sbi->s_journal_flag_rwsem){.+.+}, at: do_writepages+0xfa/0x2a0 [ 216.806013][ T1077] 1 lock held by rsyslogd/8623: [ 216.810962][ T1077] #0: ffff888098f5d860 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 [ 216.819632][ T1077] 2 locks held by getty/8713: [ 216.824307][ T1077] #0: ffff8880a1ca4090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 216.833622][ T1077] #1: ffffc90005f392e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 216.843354][ T1077] 2 locks held by getty/8714: [ 216.848090][ T1077] #0: ffff8880a0faf090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 216.857094][ T1077] #1: ffffc90005f352e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 216.866879][ T1077] 2 locks held by getty/8715: [ 216.871684][ T1077] #0: ffff8880a0b1e090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 216.880708][ T1077] #1: ffffc90005f192e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 216.890455][ T1077] 2 locks held by getty/8716: [ 216.895291][ T1077] #0: ffff8880a9486090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 216.904253][ T1077] #1: ffffc90005f112e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 216.913884][ T1077] 2 locks held by getty/8717: [ 216.918602][ T1077] #0: ffff8880a161a090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 216.927736][ T1077] #1: ffffc90005f312e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 216.938357][ T1077] 2 locks held by getty/8718: [ 216.943174][ T1077] #0: ffff888095db3090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 216.952181][ T1077] #1: ffffc90005f212e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 216.961894][ T1077] 2 locks held by getty/8719: [ 216.966649][ T1077] #0: ffff88809b09e090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 216.975654][ T1077] #1: ffffc90005f092e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 216.985692][ T1077] 1 lock held by syz-execprog/8740: [ 216.990886][ T1077] #0: ffff8880a657d3e8 (&ei->i_mmap_sem){++++}, at: ext4_filemap_fault+0x7e/0xb2 [ 217.000343][ T1077] [ 217.002674][ T1077] ============================================= [ 217.002674][ T1077] [ 217.011225][ T1077] NMI backtrace for cpu 1 [ 217.015614][ T1077] CPU: 1 PID: 1077 Comm: khungtaskd Not tainted 5.4.0-rc4-next-20191024 #0 [ 217.024474][ T1077] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 217.034675][ T1077] Call Trace: [ 217.037971][ T1077] dump_stack+0x172/0x1f0 [ 217.042315][ T1077] nmi_cpu_backtrace.cold+0x70/0xb2 [ 217.047512][ T1077] ? vprintk_func+0x86/0x189 [ 217.052109][ T1077] ? lapic_can_unplug_cpu.cold+0x3a/0x3a [ 217.061132][ T1077] nmi_trigger_cpumask_backtrace+0x23b/0x28b [ 217.067469][ T1077] arch_trigger_cpumask_backtrace+0x14/0x20 [ 217.073967][ T1077] watchdog+0xc8f/0x1350 [ 217.078222][ T1077] kthread+0x361/0x430 [ 217.082463][ T1077] ? reset_hung_task_detector+0x30/0x30 [ 217.088025][ T1077] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 217.094964][ T1077] ret_from_fork+0x24/0x30 [ 217.099491][ T1077] Sending NMI from CPU 1 to CPUs 0: [ 217.105519][ C0] NMI backtrace for cpu 0 [ 217.105525][ C0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.4.0-rc4-next-20191024 #0 [ 217.105531][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 217.105535][ C0] RIP: 0010:update_group_capacity+0xa/0x920 [ 217.105546][ C0] Code: e8 0b 84 5b 00 e9 57 fd ff ff 48 8b 7d c8 e8 1d 84 5b 00 e9 49 fe ff ff 0f 1f 84 00 00 00 00 00 48 b8 00 00 00 00 00 fc ff df <55> 48 89 e5 41 57 41 56 49 89 fe 48 83 c7 08 48 89 fa 41 55 48 c1 [ 217.105549][ C0] RSP: 0018:ffff8880ae809878 EFLAGS: 00000246 [ 217.105557][ C0] RAX: dffffc0000000000 RBX: ffff8880ae809a50 RCX: ffffffff8153db8d [ 217.105561][ C0] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8880a9813000 [ 217.105566][ C0] RBP: ffff8880ae809b20 R08: 1ffff110153038a4 R09: ffffed10153038a5 [ 217.105571][ C0] R10: ffffed10153038a4 R11: ffff8880a981c527 R12: dffffc0000000000 [ 217.105575][ C0] R13: ffff8880a981c520 R14: ffff8880ae809af8 R15: ffff8880ae809c30 [ 217.105580][ C0] FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 [ 217.105584][ C0] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 217.105589][ C0] CR2: 000000c420000240 CR3: 00000000a5df3000 CR4: 00000000001406f0 [ 217.105594][ C0] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 217.105599][ C0] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 217.105601][ C0] Call Trace: [ 217.105604][ C0] [ 217.105607][ C0] ? find_busiest_group+0x2b1/0x31b0 [ 217.105611][ C0] ? rcu_read_lock_sched_held+0x9c/0xd0 [ 217.105614][ C0] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 217.105618][ C0] ? __msecs_to_jiffies+0x4a/0x60 [ 217.105621][ C0] ? __sanitizer_cov_trace_cmp8+0x18/0x20 [ 217.105625][ C0] ? find_next_and_bit+0x19a/0x200 [ 217.105628][ C0] ? update_group_capacity+0x920/0x920 [ 217.105631][ C0] ? __kasan_check_read+0x11/0x20 [ 217.105635][ C0] ? mark_lock+0xc2/0x1220 [ 217.105638][ C0] ? __kasan_check_read+0x11/0x20 [ 217.105641][ C0] ? __kasan_check_read+0x11/0x20 [ 217.105645][ C0] ? activate_task+0x212/0x490 [ 217.105649][ C0] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 217.105652][ C0] ? find_next_and_bit+0x19a/0x200 [ 217.105655][ C0] load_balance+0x389/0x2a90 [ 217.105658][ C0] ? __kasan_check_read+0x11/0x20 [ 217.105661][ C0] ? __lock_acquire+0x16f2/0x4a00 [ 217.105665][ C0] ? find_busiest_group+0x31b0/0x31b0 [ 217.105668][ C0] ? rcu_read_lock_held+0x9c/0xb0 [ 217.105672][ C0] ? rcu_read_lock_held_common+0x130/0x130 [ 217.105675][ C0] rebalance_domains+0x66a/0xba0 [ 217.105679][ C0] ? load_balance+0x2a90/0x2a90 [ 217.105682][ C0] _nohz_idle_balance+0x336/0x3f0 [ 217.105686][ C0] run_rebalance_domains+0x1c6/0x2d0 [ 217.105689][ C0] __do_softirq+0x262/0x98c [ 217.105692][ C0] ? sched_clock_cpu+0x1b/0x1b0 [ 217.105695][ C0] irq_exit+0x19b/0x1e0 [ 217.105699][ C0] scheduler_ipi+0x38c/0x610 [ 217.105702][ C0] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 217.105705][ C0] smp_reschedule_interrupt+0x78/0x4c0 [ 217.105709][ C0] reschedule_interrupt+0xf/0x20 [ 217.105711][ C0] [ 217.105715][ C0] RIP: 0010:native_safe_halt+0xe/0x10 [ 217.105725][ C0] Code: a8 95 5a fa eb 8a 90 90 90 90 90 90 e9 07 00 00 00 0f 00 2d 84 a7 53 00 f4 c3 66 90 e9 07 00 00 00 0f 00 2d 74 a7 53 00 fb f4 90 55 48 89 e5 41 57 41 56 41 55 41 54 53 e8 be 75 0c fa e8 79 [ 217.105728][ C0] RSP: 0018:ffffffff88e07ce8 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff02 [ 217.105737][ C0] RAX: 1ffffffff11e643f RBX: ffffffff88e7a1c0 RCX: 0000000000000000 [ 217.105741][ C0] RDX: dffffc0000000000 RSI: 0000000000000006 RDI: ffffffff88e7aa5c [ 217.105746][ C0] RBP: ffffffff88e07d18 R08: ffffffff88e7a1c0 R09: 0000000000000000 [ 217.105751][ C0] R10: 0000000000000000 R11: 0000000000000000 R12: dffffc0000000000 [ 217.105755][ C0] R13: ffffffff89c81680 R14: 0000000000000000 R15: 0000000000000000 [ 217.105758][ C0] ? default_idle+0x4e/0x360 [ 217.105761][ C0] arch_cpu_idle+0xa/0x10 [ 217.105764][ C0] default_idle_call+0x84/0xb0 [ 217.105767][ C0] do_idle+0x3b7/0x6e0 [ 217.105771][ C0] ? retint_kernel+0x2b/0x2b [ 217.105774][ C0] ? arch_cpu_idle_exit+0x80/0x80 [ 217.105777][ C0] ? do_idle+0x387/0x6e0 [ 217.105780][ C0] cpu_startup_entry+0x1b/0x20 [ 217.105783][ C0] rest_init+0x23b/0x371 [ 217.105786][ C0] arch_call_rest_init+0xe/0x1b [ 217.105789][ C0] start_kernel+0x904/0x943 [ 217.105793][ C0] ? mem_encrypt_init+0xb/0xb [ 217.105796][ C0] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 217.105799][ C0] ? x86_family+0x41/0x50 [ 217.105803][ C0] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 217.105807][ C0] x86_64_start_reservations+0x29/0x2b [ 217.105810][ C0] x86_64_start_kernel+0x77/0x7b [ 217.105813][ C0] secondary_startup_64+0xa4/0xb0 [ 217.106679][ T1077] Kernel panic - not syncing: hung_task: blocked tasks [ 217.581795][ T1077] CPU: 1 PID: 1077 Comm: khungtaskd Not tainted 5.4.0-rc4-next-20191024 #0 [ 217.590582][ T1077] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 217.600641][ T1077] Call Trace: [ 217.604106][ T1077] dump_stack+0x172/0x1f0 [ 217.608442][ T1077] panic+0x2e3/0x75c [ 217.612482][ T1077] ? add_taint.cold+0x16/0x16 [ 217.617167][ T1077] ? lapic_can_unplug_cpu.cold+0x3a/0x3a [ 217.623040][ T1077] ? ___preempt_schedule+0x16/0x18 [ 217.628164][ T1077] ? nmi_trigger_cpumask_backtrace+0x21b/0x28b [ 217.634598][ T1077] ? nmi_trigger_cpumask_backtrace+0x24c/0x28b [ 217.640873][ T1077] ? nmi_trigger_cpumask_backtrace+0x256/0x28b [ 217.647043][ T1077] ? nmi_trigger_cpumask_backtrace+0x21b/0x28b [ 217.653328][ T1077] watchdog+0xca0/0x1350 [ 217.657586][ T1077] kthread+0x361/0x430 [ 217.661679][ T1077] ? reset_hung_task_detector+0x30/0x30 [ 217.667428][ T1077] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 217.673325][ T1077] ret_from_fork+0x24/0x30 [ 217.679639][ T1077] Kernel Offset: disabled [ 217.684066][ T1077] Rebooting in 86400 seconds..