[ 56.504951][ T23] audit: type=1800 audit(1571970490.976:25): pid=8511 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 56.539470][ T23] audit: type=1800 audit(1571970490.976:26): pid=8511 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 56.560904][ T23] audit: type=1800 audit(1571970490.976:27): pid=8511 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. [ 57.131256][ T8578] sshd (8578) used greatest stack depth: 22888 bytes left [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.46' (ECDSA) to the list of known hosts. syzkaller login: [ 216.429368][ T1075] INFO: task khugepaged:1082 blocked for more than 143 seconds. [ 216.437120][ T1075] Not tainted 5.4.0-rc4-next-20191024 #0 [ 216.443390][ T1075] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 216.452130][ T1075] khugepaged D27840 1082 2 0x80004000 [ 216.458917][ T1075] Call Trace: [ 216.462262][ T1075] __schedule+0x94a/0x1e70 [ 216.466728][ T1075] ? __sched_text_start+0x8/0x8 [ 216.471642][ T1075] ? blk_insert_cloned_request+0x530/0x530 [ 216.477571][ T1075] ? _raw_spin_unlock_irq+0x23/0x80 [ 216.483435][ T1075] ? __lock_page+0x3d9/0xab0 [ 216.488033][ T1075] ? _raw_spin_unlock_irq+0x23/0x80 [ 216.493591][ T1075] schedule+0xd9/0x260 [ 216.497688][ T1075] io_schedule+0x1c/0x70 [ 216.502694][ T1075] __lock_page+0x422/0xab0 [ 216.507133][ T1075] ? wait_on_page_bit+0xa60/0xa60 [ 216.512223][ T1075] ? page_cache_next_miss+0x340/0x340 [ 216.517727][ T1075] ? ___might_sleep+0x163/0x2c0 [ 216.522650][ T1075] ? __might_sleep+0x95/0x190 [ 216.527352][ T1075] mpage_prepare_extent_to_map+0xb3f/0xf90 [ 216.533237][ T1075] ? mpage_process_page_bufs+0x780/0x780 [ 216.538882][ T1075] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 216.544908][ T1075] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 216.551777][ T1075] ext4_writepages+0xb6a/0x2e70 [ 216.556669][ T1075] ? ext4_mark_inode_dirty+0x9b0/0x9b0 [ 216.562191][ T1075] ? 0xffffffff81000000 [ 216.566367][ T1075] ? mark_lock+0xc2/0x1220 [ 216.570867][ T1075] ? prep_new_page+0x19f/0x200 [ 216.575657][ T1075] ? wbc_attach_and_unlock_inode+0x515/0x920 [ 216.581724][ T1075] ? find_held_lock+0x35/0x130 [ 216.586501][ T1075] ? wbc_attach_and_unlock_inode+0x515/0x920 [ 216.592539][ T1075] ? ext4_mark_inode_dirty+0x9b0/0x9b0 [ 216.598032][ T1075] do_writepages+0xfa/0x2a0 [ 216.602598][ T1075] ? do_writepages+0xfa/0x2a0 [ 216.607279][ T1075] ? lock_downgrade+0x920/0x920 [ 216.612208][ T1075] ? page_writeback_cpu_online+0x20/0x20 [ 216.617907][ T1075] ? __kasan_check_read+0x11/0x20 [ 216.624050][ T1075] ? do_raw_spin_unlock+0x57/0x270 [ 216.629173][ T1075] ? _raw_spin_unlock+0x28/0x40 [ 216.634187][ T1075] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 216.640502][ T1075] ? wbc_attach_and_unlock_inode+0x5bf/0x920 [ 216.646502][ T1075] __filemap_fdatawrite_range+0x2bc/0x3b0 [ 216.652290][ T1075] ? delete_from_page_cache_batch+0xfe0/0xfe0 [ 216.658383][ T1075] ? lockdep_hardirqs_on+0x421/0x5e0 [ 216.663724][ T1075] filemap_flush+0x24/0x30 [ 216.669798][ T1075] collapse_file+0x36b1/0x41a0 [ 216.674700][ T1075] ? rcu_lockdep_current_cpu_online+0xe3/0x130 [ 216.681042][ T1075] ? khugepaged+0x2250/0x4360 [ 216.685737][ T1075] ? trace_event_raw_event_mm_collapse_huge_page_isolate+0x370/0x370 [ 216.694215][ T1075] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 216.700060][ T1075] ? khugepaged_find_target_node+0x142/0x180 [ 216.706065][ T1075] khugepaged+0x2da9/0x4360 [ 216.710627][ T1075] ? __kasan_check_read+0x11/0x20 [ 216.715848][ T1075] ? __lock_acquire+0x16f2/0x4a00 [ 216.720951][ T1075] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 216.726597][ T1075] ? lock_downgrade+0x920/0x920 [ 216.731544][ T1075] ? finish_wait+0x260/0x260 [ 216.736275][ T1075] ? lockdep_hardirqs_on+0x421/0x5e0 [ 216.741796][ T1075] ? trace_hardirqs_on+0x67/0x240 [ 216.747077][ T1075] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 216.753404][ T1075] ? __kthread_parkme+0x108/0x1c0 [ 216.758479][ T1075] ? __kasan_check_read+0x11/0x20 [ 216.763937][ T1075] kthread+0x361/0x430 [ 216.768022][ T1075] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 216.773849][ T1075] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 216.779632][ T1075] ret_from_fork+0x24/0x30 [ 216.784137][ T1075] INFO: task kworker/u4:5:3494 blocked for more than 143 seconds. [ 216.792229][ T1075] Not tainted 5.4.0-rc4-next-20191024 #0 [ 216.798387][ T1075] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 216.807647][ T1075] kworker/u4:5 D24344 3494 2 0x80004000 [ 216.814060][ T1075] Workqueue: writeback wb_workfn (flush-8:0) [ 216.820202][ T1075] Call Trace: [ 216.823944][ T1075] __schedule+0x94a/0x1e70 [ 216.828372][ T1075] ? __sched_text_start+0x8/0x8 [ 216.833273][ T1075] ? blk_insert_cloned_request+0x530/0x530 [ 216.839092][ T1075] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 216.845379][ T1075] ? kthread_data+0x58/0xc0 [ 216.849950][ T1075] schedule+0xd9/0x260 [ 216.854024][ T1075] io_schedule+0x1c/0x70 [ 216.858429][ T1075] __lock_page+0x422/0xab0 [ 216.862910][ T1075] ? wait_on_page_bit+0xa60/0xa60 [ 216.867961][ T1075] ? page_cache_next_miss+0x340/0x340 [ 216.873386][ T1075] ? ___might_sleep+0x163/0x2c0 [ 216.878248][ T1075] ? __might_sleep+0x95/0x190 [ 216.882983][ T1075] mpage_prepare_extent_to_map+0xb3f/0xf90 [ 216.888812][ T1075] ? mpage_process_page_bufs+0x780/0x780 [ 216.894720][ T1075] ? rcu_read_lock_sched_held+0x9c/0xd0 [ 216.900350][ T1075] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 216.906504][ T1075] ? kmem_cache_alloc_node_trace+0x56f/0x750 [ 216.912544][ T1075] ext4_writepages+0x954/0x2e70 [ 216.917408][ T1075] ? ___might_sleep+0x163/0x2c0 [ 216.922321][ T1075] ? __might_sleep+0x80/0x190 [ 216.927009][ T1075] ? print_usage_bug+0xb2/0xd0 [ 216.931896][ T1075] ? ext4_mark_inode_dirty+0x9b0/0x9b0 [ 216.937364][ T1075] ? __kasan_check_read+0x11/0x20 [ 216.942452][ T1075] ? __lock_acquire+0x16f2/0x4a00 [ 216.947799][ T1075] ? __kasan_check_read+0x11/0x20 [ 216.952997][ T1075] ? mark_lock+0xc2/0x1220 [ 216.957441][ T1075] ? mark_held_locks+0xf0/0xf0 [ 216.962279][ T1075] ? __kasan_check_read+0x11/0x20 [ 216.967326][ T1075] ? ext4_mark_inode_dirty+0x9b0/0x9b0 [ 216.973731][ T1075] do_writepages+0xfa/0x2a0 [ 216.978366][ T1075] ? do_writepages+0xfa/0x2a0 [ 216.983125][ T1075] ? page_writeback_cpu_online+0x20/0x20 [ 216.988877][ T1075] ? rcu_lockdep_current_cpu_online+0xe3/0x130 [ 216.995105][ T1075] ? rcu_read_lock_sched_held+0x9c/0xd0 [ 217.000704][ T1075] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 217.006700][ T1075] __writeback_single_inode+0x136/0x1400 [ 217.013439][ T1075] ? _raw_spin_unlock+0x28/0x40 [ 217.018393][ T1075] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 217.024678][ T1075] ? wbc_attach_and_unlock_inode+0x5bf/0x920 [ 217.030702][ T1075] writeback_sb_inodes+0x596/0xf20 [ 217.035899][ T1075] ? __writeback_single_inode+0x1400/0x1400 [ 217.041828][ T1075] ? trylock_super+0x22/0x110 [ 217.046534][ T1075] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 217.053807][ T1075] __writeback_inodes_wb+0xc3/0x260 [ 217.059024][ T1075] wb_writeback+0x910/0xd90 [ 217.063595][ T1075] ? writeback_inodes_wb.constprop.0+0x1a0/0x1a0 [ 217.069987][ T1075] ? get_nr_dirty_inodes+0xe2/0x140 [ 217.075194][ T1075] wb_workfn+0xa8a/0x1220 [ 217.079601][ T1075] ? inode_wait_for_writeback+0x40/0x40 [ 217.086121][ T1075] ? rcu_lockdep_current_cpu_online+0xe3/0x130 [ 217.092355][ T1075] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 217.098349][ T1075] ? trace_hardirqs_on+0x67/0x240 [ 217.103498][ T1075] process_one_work+0x9af/0x1740 [ 217.108472][ T1075] ? pwq_dec_nr_in_flight+0x320/0x320 [ 217.113922][ T1075] ? lock_acquire+0x190/0x410 [ 217.118649][ T1075] worker_thread+0x98/0xe40 [ 217.124167][ T1075] ? trace_hardirqs_on+0x67/0x240 [ 217.129226][ T1075] kthread+0x361/0x430 [ 217.133366][ T1075] ? process_one_work+0x1740/0x1740 [ 217.138564][ T1075] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 217.144345][ T1075] ret_from_fork+0x24/0x30 [ 217.148781][ T1075] [ 217.148781][ T1075] Showing all locks held in the system: [ 217.156565][ T1075] 1 lock held by khungtaskd/1075: [ 217.161626][ T1075] #0: ffffffff88faba80 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x279 [ 217.171033][ T1075] 1 lock held by khugepaged/1082: [ 217.176051][ T1075] #0: ffff88809bb7e990 (&sbi->s_journal_flag_rwsem){.+.+}, at: do_writepages+0xfa/0x2a0 [ 217.185959][ T1075] 4 locks held by kworker/u4:5/3494: [ 217.191283][ T1075] #0: ffff8880a76aa528 ((wq_completion)writeback){+.+.}, at: process_one_work+0x88b/0x1740 [ 217.201608][ T1075] #1: ffff88809cf47dc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0x8c1/0x1740 [ 217.213997][ T1075] #2: ffff88809bb7c0d8 (&type->s_umount_key#32){++++}, at: trylock_super+0x22/0x110 [ 217.223751][ T1075] #3: ffff88809bb7e990 (&sbi->s_journal_flag_rwsem){.+.+}, at: do_writepages+0xfa/0x2a0 [ 217.233744][ T1075] 1 lock held by rsyslogd/8549: [ 217.239116][ T1075] #0: ffff88809d21cba0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 [ 217.247801][ T1075] 2 locks held by getty/8639: [ 217.252534][ T1075] #0: ffff88809a4d9090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 217.261537][ T1075] #1: ffffc90005f3f2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 217.271422][ T1075] 2 locks held by getty/8640: [ 217.276097][ T1075] #0: ffff888092892090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 217.285096][ T1075] #1: ffffc90005f212e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 217.295298][ T1075] 2 locks held by getty/8641: [ 217.300025][ T1075] #0: ffff8880a8618090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 217.309203][ T1075] #1: ffffc90005f392e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 217.319038][ T1075] 2 locks held by getty/8642: [ 217.323860][ T1075] #0: ffff8880a4b4b090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 217.332909][ T1075] #1: ffffc90005f1d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 217.342724][ T1075] 2 locks held by getty/8643: [ 217.347403][ T1075] #0: ffff8880933cc090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 217.356427][ T1075] #1: ffffc90005f432e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 217.366049][ T1075] 2 locks held by getty/8644: [ 217.370801][ T1075] #0: ffff88808e173090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 217.381439][ T1075] #1: ffffc90005f292e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 217.391262][ T1075] 2 locks held by getty/8645: [ 217.395936][ T1075] #0: ffff8880a9a37090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 217.404935][ T1075] #1: ffffc90005f112e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 217.414575][ T1075] 1 lock held by syz-execprog/8664: [ 217.419813][ T1075] #0: ffff88808f5e63e8 (&ei->i_mmap_sem){++++}, at: ext4_filemap_fault+0x7e/0xb2 [ 217.429076][ T1075] [ 217.431453][ T1075] ============================================= [ 217.431453][ T1075] [ 217.439897][ T1075] NMI backtrace for cpu 0 [ 217.444254][ T1075] CPU: 0 PID: 1075 Comm: khungtaskd Not tainted 5.4.0-rc4-next-20191024 #0 [ 217.452823][ T1075] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 217.462869][ T1075] Call Trace: [ 217.466150][ T1075] dump_stack+0x172/0x1f0 [ 217.470467][ T1075] nmi_cpu_backtrace.cold+0x70/0xb2 [ 217.475746][ T1075] ? vprintk_func+0x86/0x189 [ 217.480323][ T1075] ? lapic_can_unplug_cpu.cold+0x3a/0x3a [ 217.485956][ T1075] nmi_trigger_cpumask_backtrace+0x23b/0x28b [ 217.491927][ T1075] arch_trigger_cpumask_backtrace+0x14/0x20 [ 217.498013][ T1075] watchdog+0xc8f/0x1350 [ 217.502287][ T1075] kthread+0x361/0x430 [ 217.506407][ T1075] ? reset_hung_task_detector+0x30/0x30 [ 217.512280][ T1075] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 217.518016][ T1075] ret_from_fork+0x24/0x30 [ 217.522675][ T1075] Sending NMI from CPU 0 to CPUs 1: [ 217.527935][ C1] NMI backtrace for cpu 1 skipped: idling at native_safe_halt+0xe/0x10 [ 217.528896][ T1075] Kernel panic - not syncing: hung_task: blocked tasks [ 217.543595][ T1075] CPU: 0 PID: 1075 Comm: khungtaskd Not tainted 5.4.0-rc4-next-20191024 #0 [ 217.553391][ T1075] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 217.563453][ T1075] Call Trace: [ 217.566749][ T1075] dump_stack+0x172/0x1f0 [ 217.571059][ T1075] panic+0x2e3/0x75c [ 217.574939][ T1075] ? add_taint.cold+0x16/0x16 [ 217.579616][ T1075] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 217.585322][ T1075] ? printk_safe_flush+0xf2/0x140 [ 217.590340][ T1075] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 217.597294][ T1075] ? nmi_trigger_cpumask_backtrace+0x224/0x28b [ 217.604418][ T1075] ? nmi_trigger_cpumask_backtrace+0x21b/0x28b [ 217.610568][ T1075] watchdog+0xca0/0x1350 [ 217.614809][ T1075] kthread+0x361/0x430 [ 217.618872][ T1075] ? reset_hung_task_detector+0x30/0x30 [ 217.624415][ T1075] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 217.630133][ T1075] ret_from_fork+0x24/0x30 [ 217.635410][ T1075] Kernel Offset: disabled [ 217.639752][ T1075] Rebooting in 86400 seconds..