Warning: Permanently added '10.128.0.175' (ECDSA) to the list of known hosts. executing program [ 1001.324249] INFO: task syz-executor391:7978 blocked for more than 140 seconds. [ 1001.331673] Not tainted 4.14.281-syzkaller #0 [ 1001.344200] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1001.352607] syz-executor391 D27040 7978 7977 0x00000004 [ 1001.358776] Call Trace: [ 1001.361377] __schedule+0x88b/0x1de0 [ 1001.365907] ? io_schedule_timeout+0x140/0x140 [ 1001.370498] ? trace_hardirqs_on+0x10/0x10 [ 1001.375607] schedule+0x8d/0x1b0 [ 1001.378975] schedule_timeout+0x80a/0xe90 [ 1001.383120] ? HARDIRQ_verbose+0x10/0x10 [ 1001.388386] ? usleep_range+0x130/0x130 [ 1001.392362] ? wait_for_common+0x26a/0x430 [ 1001.397500] ? mark_held_locks+0xa6/0xf0 [ 1001.401563] ? _raw_spin_unlock_irq+0x24/0x80 [ 1001.406933] wait_for_common+0x272/0x430 [ 1001.411004] ? out_of_line_wait_on_atomic_t+0x1a0/0x1a0 [ 1001.417245] ? wake_up_q+0xd0/0xd0 [ 1001.420789] ? _raw_spin_unlock_irq+0x24/0x80 [ 1001.426862] flush_work+0x3fe/0x770 [ 1001.430490] ? worker_thread+0xff0/0xff0 [ 1001.435412] ? flush_workqueue_prep_pwqs+0x470/0x470 [ 1001.440525] ? trace_hardirqs_on_caller+0x3a8/0x580 [ 1001.446486] ? _raw_spin_unlock_irqrestore+0x66/0xe0 [ 1001.451589] ? __pollwait+0x20f/0x3f0 [ 1001.456252] n_tty_poll+0x4de/0x7d0 [ 1001.459877] ? commit_echoes+0x1e0/0x1e0 [ 1001.463931] tty_poll+0x129/0x1a0 [ 1001.468592] ? tty_release+0x10d0/0x10d0 [ 1001.472653] do_select+0xa83/0x1290 [ 1001.477161] ? select_estimate_accuracy+0x2b0/0x2b0 [ 1001.482177] ? tracing_generic_entry_update+0x162/0x1d0 [ 1001.488423] ? perf_swevent_event+0x34/0x460 [ 1001.492840] ? check_preemption_disabled+0x35/0x240 [ 1001.498827] ? poll_initwait+0x170/0x170 [ 1001.502890] ? compat_get_fd_set+0x70/0x70 [ 1001.508010] ? compat_get_fd_set+0x70/0x70 [ 1001.512245] ? compat_get_fd_set+0x70/0x70 [ 1001.517349] ? compat_get_fd_set+0x70/0x70 [ 1001.521584] ? compat_get_fd_set+0x70/0x70 [ 1001.527794] ? compat_get_fd_set+0x70/0x70 [ 1001.532044] ? compat_get_fd_set+0x70/0x70 [ 1001.537172] ? compat_get_fd_set+0x70/0x70 [ 1001.541421] ? compat_get_fd_set+0x70/0x70 [ 1001.546566] ? lock_downgrade+0x740/0x740 [ 1001.550811] ? __might_fault+0x177/0x1b0 [ 1001.556495] core_sys_select+0x32f/0x6a0 [ 1001.560564] ? poll_select_set_timeout+0x120/0x120 [ 1001.566478] ? trace_hardirqs_on+0x10/0x10 [ 1001.570739] ? __fd_install+0x1ec/0x5c0 [ 1001.575614] ? lock_acquire+0x170/0x3f0 [ 1001.579595] ? lock_downgrade+0x740/0x740 [ 1001.583738] ? __fd_install+0x227/0x5c0 [ 1001.588962] SyS_pselect6+0x358/0x3c0 [ 1001.592766] ? SyS_select+0x170/0x170 [ 1001.597588] ? SyS_socket+0x12f/0x1b0 [ 1001.601477] ? move_addr_to_kernel+0x60/0x60 [ 1001.606832] ? do_syscall_64+0x4c/0x640 [ 1001.610815] ? SyS_select+0x170/0x170 [ 1001.615585] do_syscall_64+0x1d5/0x640 [ 1001.619476] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 1001.625553] RIP: 0033:0x7f4f60f1e3c9 [ 1001.629261] RSP: 002b:00007fffb4b174f8 EFLAGS: 00000246 ORIG_RAX: 000000000000010e [ 1001.638053] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f4f60f1e3c9 [ 1001.646051] RDX: 0000000000000000 RSI: 00000000200000c0 RDI: 0000000000000040 [ 1001.653357] RBP: 00007fffb4b17530 R08: 0000000000000000 R09: 0000000000000000 [ 1001.662046] R10: 0000000020000140 R11: 0000000000000246 R12: 00007f4f60ee1990 [ 1001.674182] R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000 [ 1001.681525] [ 1001.681525] Showing all locks held in the system: [ 1001.690051] 1 lock held by khungtaskd/1532: [ 1001.694547] #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a [ 1001.703600] 1 lock held by syz-executor391/7978: [ 1001.708434] #0: (&tty->ldisc_sem){++++}, at: [] tty_ldisc_ref_wait+0x22/0x80 [ 1001.717455] [ 1001.719074] ============================================= [ 1001.719074] [ 1001.734018] NMI backtrace for cpu 1 [ 1001.737759] CPU: 1 PID: 1532 Comm: khungtaskd Not tainted 4.14.281-syzkaller #0 [ 1001.745201] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 1001.754547] Call Trace: [ 1001.757129] dump_stack+0x1b2/0x281 [ 1001.760754] nmi_cpu_backtrace.cold+0x57/0x93 [ 1001.765248] ? irq_force_complete_move+0x350/0x350 [ 1001.770169] nmi_trigger_cpumask_backtrace+0x13a/0x180 [ 1001.775465] watchdog+0x5b9/0xb40 [ 1001.778910] ? hungtask_pm_notify+0x50/0x50 [ 1001.783221] kthread+0x30d/0x420 [ 1001.786575] ? kthread_create_on_node+0xd0/0xd0 [ 1001.791233] ret_from_fork+0x24/0x30 [ 1001.795041] Sending NMI from CPU 1 to CPUs 0: [ 1001.799924] NMI backtrace for cpu 0 [ 1001.799928] CPU: 0 PID: 2874 Comm: kworker/u4:4 Not tainted 4.14.281-syzkaller #0 [ 1001.799937] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 1001.799939] Workqueue: events_unbound flush_to_ldisc [ 1001.799944] task: ffff8880ac2ce500 task.stack: ffff8880ac0d8000 [ 1001.799946] RIP: 0010:mark_lock+0xa2/0x1050 [ 1001.799949] RSP: 0018:ffff8880ac0df770 EFLAGS: 00000806 [ 1001.799954] RAX: dffffc0000000000 RBX: ffffffff8ba48d30 RCX: 1ffff11015859dce [ 1001.799957] RDX: 1ffffffff17491ac RSI: ffff8880ac2cee50 RDI: ffffffff8ba48d60 [ 1001.799960] RBP: ffff8880ac2cee50 R08: 0000000000000001 R09: 0000000000040458 [ 1001.799963] R10: ffff8880ac2cee50 R11: ffff8880ac2ce500 R12: 0000000000000100 [ 1001.799966] R13: ffff8880ac2ce500 R14: ffff8880ac2cee70 R15: 0000000000000008 [ 1001.799970] FS: 0000000000000000(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000 [ 1001.799972] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1001.799976] CR2: 00007f81c3892000 CR3: 00000000a1231000 CR4: 00000000003406f0 [ 1001.799979] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1001.799982] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 1001.799984] Call Trace: [ 1001.799986] __lock_acquire+0x5fc/0x3f20 [ 1001.799988] ? mark_held_locks+0xa6/0xf0 [ 1001.799990] ? trace_hardirqs_on+0x10/0x10 [ 1001.799993] ? perf_trace_lock_acquire+0x104/0x510 [ 1001.799995] ? HARDIRQ_verbose+0x10/0x10 [ 1001.799997] ? HARDIRQ_verbose+0x10/0x10 [ 1001.799999] lock_acquire+0x170/0x3f0 [ 1001.800001] ? commit_echoes+0x4c/0x1e0 [ 1001.800004] ? commit_echoes+0x4c/0x1e0 [ 1001.800006] __mutex_lock+0xc4/0x1310 [ 1001.800008] ? commit_echoes+0x4c/0x1e0 [ 1001.800010] ? commit_echoes+0x4c/0x1e0 [ 1001.800013] ? __ww_mutex_wakeup_for_backoff+0x210/0x210 [ 1001.800015] ? lock_downgrade+0x740/0x740 [ 1001.800018] ? __ww_mutex_wakeup_for_backoff+0x210/0x210 [ 1001.800021] ? __mutex_unlock_slowpath+0x75/0x770 [ 1001.800023] ? __mutex_unlock_slowpath+0x75/0x770 [ 1001.800025] ? tty_write_room+0x69/0x80 [ 1001.800027] commit_echoes+0x4c/0x1e0 [ 1001.800030] n_tty_receive_buf_common+0x1795/0x25a0 [ 1001.800032] ? n_tty_receive_buf_common+0x25a0/0x25a0 [ 1001.800035] tty_ldisc_receive_buf+0x9e/0x170 [ 1001.800037] tty_port_default_receive_buf+0x6e/0xa0 [ 1001.800040] flush_to_ldisc+0x1e9/0x440 [ 1001.800042] process_one_work+0x793/0x14a0 [ 1001.800044] ? work_busy+0x320/0x320 [ 1001.800046] ? worker_thread+0x158/0xff0 [ 1001.800048] worker_thread+0x5cc/0xff0 [ 1001.800050] ? rescuer_thread+0xc80/0xc80 [ 1001.800052] kthread+0x30d/0x420 [ 1001.800055] ? kthread_create_on_node+0xd0/0xd0 [ 1001.800057] ret_from_fork+0x24/0x30 [ 1001.800059] Code: 00 48 69 d8 50 01 00 00 48 81 eb 50 01 00 00 48 81 c3 00 db 9e 8b 48 8d 7b 30 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 07 0c 00 00 4c 89 e0 48 23 43 30 0f 84 9c 00 [ 1001.801050] Kernel panic - not syncing: hung_task: blocked tasks [ 1002.077749] CPU: 1 PID: 1532 Comm: khungtaskd Not tainted 4.14.281-syzkaller #0 [ 1002.085185] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 1002.094526] Call Trace: [ 1002.097103] dump_stack+0x1b2/0x281 [ 1002.100721] panic+0x1f9/0x42d [ 1002.103898] ? add_taint.cold+0x16/0x16 [ 1002.107876] watchdog+0x5ca/0xb40 [ 1002.111323] ? hungtask_pm_notify+0x50/0x50 [ 1002.115634] kthread+0x30d/0x420 [ 1002.118995] ? kthread_create_on_node+0xd0/0xd0 [ 1002.123656] ret_from_fork+0x24/0x30 [ 1002.127654] Kernel Offset: disabled [ 1002.131269] Rebooting in 86400 seconds..