[ 38.525844][ T26] audit: type=1800 audit(1556004874.547:26): pid=7620 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0
[ 38.558981][ T26] audit: type=1800 audit(1556004874.547:27): pid=7620 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2436 res=0
[ 38.579954][ T26] audit: type=1800 audit(1556004874.557:28): pid=7620 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="ssh" dev="sda1" ino=2417 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.
[ 39.374579][ T26] audit: type=1800 audit(1556004875.437:29): pid=7620 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rc.local" dev="sda1" ino=2432 res=0
Debian GNU/Linux 7 syzkaller ttyS0
Warning: Permanently added '10.128.0.32' (ECDSA) to the list of known hosts.
executing program
syzkaller login: [ 476.787853][ T26] kauditd_printk_skb: 1 callbacks suppressed
[ 476.787864][ T26] audit: type=1804 audit(1556005312.847:31): pid=7771 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor573" name="/root/bus" dev="sda1" ino=2339 res=1
[ 476.892257][ C0] hrtimer: interrupt took 27669 ns
[ 662.693095][ C0] BUG: workqueue lockup - pool cpus=0 node=0 flags=0x0 nice=0 stuck for 151s!
[ 662.702343][ C0] Showing busy workqueues and worker pools:
[ 662.708472][ C0] workqueue events: flags=0x0
[ 662.713365][ C0] pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=4/256
[ 662.722101][ C0] pending: vmstat_shepherd, psi_update_work, cache_reap, check_corruption
[ 662.730955][ C0]
[ 662.730959][ C0] ======================================================
[ 662.730962][ C0] WARNING: possible circular locking dependency detected
[ 662.730964][ C0] 5.1.0-rc6 #79 Not tainted
[ 662.730968][ C0] ------------------------------------------------------
[ 662.730970][ C0] ksoftirqd/0/9 is trying to acquire lock:
[ 662.730972][ C0] 0000000038e7b405 (console_owner){-.-.}, at: console_unlock+0x3fc/0xed0
[ 662.730980][ C0]
[ 662.730982][ C0] but task is already holding lock:
[ 662.730984][ C0] 00000000c0b5977e (&(&pool->lock)->rlock){-.-.}, at: show_workqueue_state.cold+0x879/0x11dc
[ 662.730992][ C0]
[ 662.730994][ C0] which lock already depends on the new lock.
[ 662.730995][ C0]
[ 662.730997][ C0]
[ 662.731000][ C0] the existing dependency chain (in reverse order) is:
[ 662.731001][ C0]
[ 662.731002][ C0] -> #4 (&(&pool->lock)->rlock){-.-.}:
[ 662.731009][ C0] lock_acquire+0x16f/0x3f0
[ 662.731012][ C0] _raw_spin_lock+0x2f/0x40
[ 662.731014][ C0] __queue_work+0x23d/0x10e0
[ 662.731016][ C0] queue_work_on+0x192/0x200
[ 662.731018][ C0] put_pwq+0x178/0x1d0
[ 662.731020][ C0] put_pwq_unlocked.part.0+0x34/0x70
[ 662.731023][ C0] destroy_workqueue+0x623/0x700
[ 662.731025][ C0] floppy_async_init+0x2031/0x2183
[ 662.731027][ C0] async_run_entry_fn+0x126/0x570
[ 662.731030][ C0] process_one_work+0x98e/0x1790
[ 662.731032][ C0] worker_thread+0x98/0xe40
[ 662.731034][ C0] kthread+0x357/0x430
[ 662.731036][ C0] ret_from_fork+0x3a/0x50
[ 662.731037][ C0]
[ 662.731038][ C0] -> #3 (&pool->lock/1){..-.}:
[ 662.731046][ C0] lock_acquire+0x16f/0x3f0
[ 662.731049][ C0] _raw_spin_lock+0x2f/0x40
[ 662.731051][ C0] __queue_work+0x23d/0x10e0
[ 662.731053][ C0] queue_work_on+0x192/0x200
[ 662.731056][ C0] tty_flip_buffer_push+0xc5/0x100
[ 662.731058][ C0] pty_write+0x1a6/0x200
[ 662.731060][ C0] n_tty_write+0xb06/0x1150
[ 662.731062][ C0] tty_write+0x45b/0x7a0
[ 662.731064][ C0] __vfs_write+0x8d/0x110
[ 662.731066][ C0] vfs_write+0x20c/0x580
[ 662.731068][ C0] ksys_write+0x14f/0x2d0
[ 662.731070][ C0] __x64_sys_write+0x73/0xb0
[ 662.731072][ C0] do_syscall_64+0x103/0x610
[ 662.731075][ C0] entry_SYSCALL_64_after_hwframe+0x49/0xbe
[ 662.731076][ C0]
[ 662.731077][ C0] -> #2 (&(&port->lock)->rlock){-.-.}:
[ 662.731085][ C0] lock_acquire+0x16f/0x3f0
[ 662.731087][ C0] _raw_spin_lock_irqsave+0x95/0xcd
[ 662.731089][ C0] tty_port_tty_get+0x22/0x80
[ 662.731092][ C0] tty_port_default_wakeup+0x16/0x40
[ 662.731094][ C0] tty_port_tty_wakeup+0x5d/0x70
[ 662.731096][ C0] uart_write_wakeup+0x46/0x70
[ 662.731099][ C0] serial8250_tx_chars+0x4a4/0xb20
[ 662.731101][ C0] serial8250_handle_irq.part.0+0x1be/0x2e0
[ 662.731104][ C0] serial8250_default_handle_irq+0xc5/0x150
[ 662.731106][ C0] serial8250_interrupt+0xfb/0x1a0
[ 662.731109][ C0] __handle_irq_event_percpu+0x146/0x900
[ 662.731111][ C0] handle_irq_event_percpu+0x74/0x160
[ 662.731113][ C0] handle_irq_event+0xa7/0x134
[ 662.731116][ C0] handle_edge_irq+0x264/0x8e0
[ 662.731118][ C0] handle_irq+0x252/0x3d8
[ 662.731120][ C0] do_IRQ+0x99/0x1d0
[ 662.731122][ C0] ret_from_intr+0x0/0x1e
[ 662.731124][ C0] _raw_spin_unlock_irqrestore+0x95/0xe0
[ 662.731126][ C0] uart_write+0x3b6/0x6f0
[ 662.731129][ C0] n_tty_write+0x3ff/0x1150
[ 662.731131][ C0] tty_write+0x45b/0x7a0
[ 662.731133][ C0] redirected_tty_write+0xb2/0xc0
[ 662.731135][ C0] __vfs_write+0x8d/0x110
[ 662.731137][ C0] vfs_write+0x20c/0x580
[ 662.731139][ C0] ksys_write+0x14f/0x2d0
[ 662.731141][ C0] __x64_sys_write+0x73/0xb0
[ 662.731144][ C0] do_syscall_64+0x103/0x610
[ 662.731146][ C0] entry_SYSCALL_64_after_hwframe+0x49/0xbe
[ 662.731147][ C0]
[ 662.731149][ C0] -> #1 (&port_lock_key){-.-.}:
[ 662.731156][ C0] lock_acquire+0x16f/0x3f0
[ 662.731160][ C0] _raw_spin_lock_irqsave+0x95/0xcd
[ 662.731162][ C0] serial8250_console_write+0x253/0x9c0
[ 662.731165][ C0] univ8250_console_write+0x5f/0x70
[ 662.731167][ C0] console_unlock+0xb44/0xed0
[ 662.731169][ C0] vprintk_emit+0x280/0x6d0
[ 662.731171][ C0] vprintk_default+0x28/0x30
[ 662.731173][ C0] vprintk_func+0x7e/0x189
[ 662.731175][ C0] printk+0xba/0xed
[ 662.731177][ C0] register_console+0x74d/0xb50
[ 662.731180][ C0] univ8250_console_init+0x3e/0x4b
[ 662.731182][ C0] console_init+0x4f7/0x761
[ 662.731184][ C0] start_kernel+0x574/0x84f
[ 662.731187][ C0] x86_64_start_reservations+0x29/0x2b
[ 662.731189][ C0] x86_64_start_kernel+0x77/0x7b
[ 662.731198][ C0] secondary_startup_64+0xa4/0xb0
[ 662.731199][ C0]
[ 662.731201][ C0] -> #0 (console_owner){-.-.}:
[ 662.731208][ C0] __lock_acquire+0x239c/0x3fb0
[ 662.731210][ C0] lock_acquire+0x16f/0x3f0
[ 662.731212][ C0] console_unlock+0x466/0xed0
[ 662.731214][ C0] vprintk_emit+0x280/0x6d0
[ 662.731216][ C0] vprintk_default+0x28/0x30
[ 662.731219][ C0] vprintk_func+0x7e/0x189
[ 662.731221][ C0] printk+0xba/0xed
[ 662.731223][ C0] show_workqueue_state.cold+0x9e4/0x11dc
[ 662.731226][ C0] wq_watchdog_timer_fn+0x516/0x5a0
[ 662.731228][ C0] call_timer_fn+0x190/0x720
[ 662.731230][ C0] run_timer_softirq+0xd03/0x1700
[ 662.731233][ C0] __do_softirq+0x266/0x95a
[ 662.731235][ C0] run_ksoftirqd+0x8e/0x110
[ 662.731237][ C0] smpboot_thread_fn+0x6ab/0xa40
[ 662.731239][ C0] kthread+0x357/0x430
[ 662.731241][ C0] ret_from_fork+0x3a/0x50
[ 662.731243][ C0]
[ 662.731245][ C0] other info that might help us debug this:
[ 662.731246][ C0]
[ 662.731248][ C0] Chain exists of:
[ 662.731249][ C0] console_owner --> &pool->lock/1 --> &(&pool->lock)->rlock
[ 662.731259][ C0]
[ 662.731262][ C0] Possible unsafe locking scenario:
[ 662.731263][ C0]
[ 662.731265][ C0] CPU0 CPU1
[ 662.731267][ C0] ---- ----
[ 662.731268][ C0] lock(&(&pool->lock)->rlock);
[ 662.731274][ C0] lock(&pool->lock/1);
[ 662.731280][ C0] lock(&(&pool->lock)->rlock);
[ 662.731284][ C0] lock(console_owner);
[ 662.731288][ C0]
[ 662.731289][ C0] *** DEADLOCK ***
[ 662.731291][ C0]
[ 662.731293][ C0] 4 locks held by ksoftirqd/0/9:
[ 662.731294][ C0] #0: 000000000fa65e1b ((&wq_watchdog_timer)){+.-.}, at: call_timer_fn+0xda/0x720
[ 662.731303][ C0] #1: 000000000183de91 (rcu_read_lock_sched){....}, at: show_workqueue_state+0x0/0x120
[ 662.731312][ C0] #2: 00000000c0b5977e (&(&pool->lock)->rlock){-.-.}, at: show_workqueue_state.cold+0x879/0x11dc
[ 662.731321][ C0] #3: 00000000c90a8d8b (console_lock){+.+.}, at: vprintk_emit+0x267/0x6d0
[ 662.731330][ C0]
[ 662.731331][ C0] stack backtrace:
[ 662.731334][ C0] CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 5.1.0-rc6 #79
[ 662.731338][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 662.731340][ C0] Call Trace:
[ 662.731342][ C0] dump_stack+0x172/0x1f0
[ 662.731344][ C0] print_circular_bug.isra.0.cold+0x1cc/0x28f
[ 662.731347][ C0] check_prev_add.constprop.0+0xf11/0x23c0
[ 662.731349][ C0] ? check_usage+0x570/0x570
[ 662.731351][ C0] ? graph_lock+0x7b/0x200
[ 662.731353][ C0] ? __lockdep_reset_lock+0x450/0x450
[ 662.731355][ C0] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20
[ 662.731358][ C0] ? find_first_zero_bit+0x9a/0xc0
[ 662.731360][ C0] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20
[ 662.731362][ C0] __lock_acquire+0x239c/0x3fb0
[ 662.731365][ C0] ? __sanitizer_cov_trace_switch+0x49/0x80
[ 662.731367][ C0] ? mark_held_locks+0xf0/0xf0
[ 662.731369][ C0] ? kasan_check_write+0x14/0x20
[ 662.731371][ C0] lock_acquire+0x16f/0x3f0
[ 662.731373][ C0] ? console_unlock+0x3fc/0xed0
[ 662.731375][ C0] console_unlock+0x466/0xed0
[ 662.731377][ C0] ? console_unlock+0x3fc/0xed0
[ 662.731379][ C0] vprintk_emit+0x280/0x6d0
[ 662.731381][ C0] vprintk_default+0x28/0x30
[ 662.731383][ C0] vprintk_func+0x7e/0x189
[ 662.731385][ C0] ? printk+0xba/0xed
[ 662.731386][ C0] printk+0xba/0xed
[ 662.731389][ C0] ? kmsg_dump_rewind_nolock+0xe4/0xe4
[ 662.731391][ C0] ? show_workqueue_state.cold+0x879/0x11dc
[ 662.731393][ C0] show_workqueue_state.cold+0x9e4/0x11dc
[ 662.731396][ C0] ? wq_watchdog_timer_fn+0x3f9/0x5a0
[ 662.731398][ C0] ? idr_get_next+0x1a6/0x230
[ 662.731400][ C0] ? print_worker_info+0x280/0x280
[ 662.731403][ C0] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20
[ 662.731405][ C0] ? kasan_check_read+0x11/0x20
[ 662.731407][ C0] wq_watchdog_timer_fn+0x516/0x5a0
[ 662.731409][ C0] ? show_workqueue_state+0x120/0x120
[ 662.731411][ C0] call_timer_fn+0x190/0x720
[ 662.731413][ C0] ? show_workqueue_state+0x120/0x120
[ 662.731415][ C0] ? process_timeout+0x40/0x40
[ 662.731418][ C0] ? run_timer_softirq+0xcf8/0x1700
[ 662.731420][ C0] ? trace_hardirqs_on+0x67/0x230
[ 662.731422][ C0] ? kasan_check_read+0x11/0x20
[ 662.731424][ C0] ? show_workqueue_state+0x120/0x120
[ 662.731426][ C0] run_timer_softirq+0xd03/0x1700
[ 662.731428][ C0] ? add_timer+0xbe0/0xbe0
[ 662.731430][ C0] ? kvm_clock_read+0x18/0x30
[ 662.731433][ C0] ? kvm_sched_clock_read+0x9/0x20
[ 662.731435][ C0] ? sched_clock+0x2e/0x50
[ 662.731437][ C0] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20
[ 662.731440][ C0] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20
[ 662.731442][ C0] __do_softirq+0x266/0x95a
[ 662.731444][ C0] ? takeover_tasklets+0x7b0/0x7b0
[ 662.731446][ C0] run_ksoftirqd+0x8e/0x110
[ 662.731448][ C0] smpboot_thread_fn+0x6ab/0xa40
[ 662.731450][ C0] ? sort_range+0x30/0x30
[ 662.731453][ C0] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20
[ 662.731455][ C0] ? __kthread_parkme+0xfb/0x1b0
[ 662.731457][ C0] kthread+0x357/0x430
[ 662.731459][ C0] ? sort_range+0x30/0x30
[ 662.731461][ C0] ? kthread_cancel_delayed_work_sync+0x20/0x20
[ 662.731463][ C0] ret_from_fork+0x3a/0x50
[ 663.787970][ C0] workqueue events_power_efficient: flags=0x80
[ 663.794232][ C0] pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=3/256
[ 663.801073][ C0] in-flight: 12:gc_worker
[ 663.805891][ C0] pending: do_cache_clean, check_lifetime
[ 663.812091][ C0] workqueue mm_percpu_wq: flags=0x8
[ 663.817297][ C0] pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256
[ 663.824129][ C0] pending: vmstat_update
[ 663.828792][ C0] workqueue dm_bufio_cache: flags=0x8
[ 663.834187][ C0] pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256
[ 663.841029][ C0] pending: work_fn
[ 663.845152][ C0] workqueue ipv6_addrconf: flags=0x40008
[ 663.850792][ C0] pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/1
[ 663.857515][ C0] pending: addrconf_verify_work
[ 663.862762][ C0] pool 0: cpus=0 node=0 flags=0x0 nice=0 hung=152s workers=2 idle: 2996