INIT: Entering runlevel: 2 [info] Using makefile-style concurrent boot in runlevel 2. [....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [....] 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 'ci-upstream-net-kasan-gce-8,10.128.0.36' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 615.391110] INFO: task syzkaller517387:3011 blocked for more than 120 seconds. [ 615.398589] Not tainted 4.13.0-rc6+ #23 [ 615.403318] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 615.411288] syzkaller517387 D23296 3011 3009 0x00000000 [ 615.416977] Call Trace: [ 615.419608] __schedule+0x8e8/0x2070 [ 615.423343] ? __sched_text_start+0x8/0x8 [ 615.427510] ? check_noncircular+0x20/0x20 [ 615.431762] ? prepare_to_wait_exclusive+0x192/0x530 [ 615.436857] ? lock_downgrade+0x990/0x990 [ 615.440998] ? check_irq_usage+0xb1/0xe0 [ 615.445068] ? do_raw_spin_trylock+0x190/0x190 [ 615.449660] ? __lock_acquire+0x2de2/0x3dc0 [ 615.453978] ? mark_held_locks+0xaf/0x100 [ 615.458134] schedule+0x108/0x440 [ 615.461584] ? lock_downgrade+0x990/0x990 [ 615.465730] ? __schedule+0x2070/0x2070 [ 615.469698] ? mark_held_locks+0xaf/0x100 [ 615.473840] ? __local_bh_enable_ip+0x9d/0x160 [ 615.478415] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 615.483499] ? __lock_sock+0x1d7/0x2f0 [ 615.487382] ? trace_hardirqs_on+0xd/0x10 [ 615.491528] ? __local_bh_enable_ip+0x9d/0x160 [ 615.496118] __lock_sock+0x1dc/0x2f0 [ 615.499829] ? proto_unregister+0x5e0/0x5e0 [ 615.504143] ? finish_wait+0x490/0x490 [ 615.508036] ? lock_sock_nested+0x44/0x110 [ 615.512266] lock_sock_nested+0xf3/0x110 [ 615.516343] tcp_sendmsg+0x21/0x50 [ 615.519890] inet_sendmsg+0x11f/0x5e0 [ 615.523701] ? inet_recvmsg+0x5f0/0x5f0 [ 615.527670] ? selinux_socket_sendmsg+0x36/0x40 [ 615.532333] ? security_socket_sendmsg+0x89/0xb0 [ 615.537083] ? inet_recvmsg+0x5f0/0x5f0 [ 615.541097] sock_sendmsg+0xca/0x110 [ 615.544808] kernel_sendmsg+0x47/0x60 [ 615.548606] sock_no_sendpage+0x1cc/0x280 [ 615.552755] ? sock_kzfree_s+0x60/0x60 [ 615.556657] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 615.561671] tcp_sendpage_locked+0x10b/0x160 [ 615.566085] tcp_sendpage+0x43/0x60 [ 615.569710] ? tcp_sendpage_locked+0x160/0x160 [ 615.574304] inet_sendpage+0x1aa/0x660 [ 615.578190] ? inet_sendmsg+0x5e0/0x5e0 [ 615.582174] ? inet_sendmsg+0x5e0/0x5e0 [ 615.586147] kernel_sendpage+0x8d/0xe0 [ 615.590046] sock_sendpage+0x8c/0xc0 [ 615.593751] ? kernel_sendpage+0xe0/0xe0 [ 615.597809] pipe_to_sendpage+0x290/0x3b0 [ 615.601952] ? direct_splice_actor+0x180/0x180 [ 615.606540] ? check_same_owner+0x320/0x320 [ 615.610863] ? splice_from_pipe_next.part.9+0x22a/0x2e0 [ 615.616239] __splice_from_pipe+0x343/0x750 [ 615.620557] ? direct_splice_actor+0x180/0x180 [ 615.625142] splice_from_pipe+0x1e9/0x330 [ 615.629279] ? direct_splice_actor+0x180/0x180 [ 615.633856] ? splice_shrink_spd+0xb0/0xb0 [ 615.638095] ? security_file_permission+0x89/0x1e0 [ 615.643031] generic_splice_sendpage+0x40/0x50 [ 615.647616] ? splice_from_pipe+0x330/0x330 [ 615.651941] SyS_splice+0x7b7/0x1610 [ 615.655648] ? vmacache_find+0x61/0x270 [ 615.659630] ? compat_SyS_vmsplice+0x250/0x250 [ 615.664199] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 615.669217] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 615.673985] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 615.678737] RIP: 0033:0x43fd59 [ 615.681918] RSP: 002b:00007ffcbfb19c98 EFLAGS: 00000212 ORIG_RAX: 0000000000000113 [ 615.689622] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fd59 [ 615.696879] RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000004 [ 615.704148] RBP: 0000000000000086 R08: 0000000810000004 R09: 000000000000000a [ 615.711419] R10: 0000000000000000 R11: 0000000000000212 R12: 00000000004016c0 [ 615.718713] R13: 0000000000401750 R14: 0000000000000000 R15: 0000000000000000 [ 615.725994] [ 615.725994] Showing all locks held in the system: [ 615.732317] 2 locks held by khungtaskd/636: [ 615.736642] #0: (rcu_read_lock){......}, at: [] watchdog+0x1c5/0xd60 [ 615.744888] #1: (tasklist_lock){.+.+..}, at: [] debug_show_all_locks+0xd2/0x410 [ 615.754094] 1 lock held by rsyslogd/2898: [ 615.758261] #0: (&f->f_pos_lock){+.+.+.}, at: [] __fdget_pos+0x12b/0x190 [ 615.766879] 2 locks held by getty/2980: [ 615.770867] #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x37/0x40 [ 615.779767] #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x2ef/0x1a40 [ 615.789260] 2 locks held by getty/2981: [ 615.793230] #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x37/0x40 [ 615.802102] #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x2ef/0x1a40 [ 615.811559] 2 locks held by getty/2982: [ 615.815527] #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x37/0x40 [ 615.824373] #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x2ef/0x1a40 [ 615.833837] 2 locks held by getty/2983: [ 615.837797] #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x37/0x40 [ 615.846645] #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x2ef/0x1a40 [ 615.856101] 2 locks held by getty/2984: [ 615.860069] #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x37/0x40 [ 615.868910] #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x2ef/0x1a40 [ 615.878380] 2 locks held by getty/2985: [ 615.882344] #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x37/0x40 [ 615.891228] #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x2ef/0x1a40 [ 615.900718] 2 locks held by getty/2986: [ 615.904721] #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x37/0x40 [ 615.913599] #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x2ef/0x1a40 [ 615.923083] 2 locks held by syzkaller517387/3011: [ 615.927916] #0: (&pipe->mutex/1){+.+.+.}, at: [] pipe_lock+0x56/0x70 [ 615.936179] #1: (sk_lock-AF_INET){+.+.+.}, at: [] tcp_sendpage+0x2e/0x60 [ 615.944776] [ 615.946397] ============================================= [ 615.946397] [ 615.953410] NMI backtrace for cpu 1 [ 615.957035] CPU: 1 PID: 636 Comm: khungtaskd Not tainted 4.13.0-rc6+ #23 [ 615.963842] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 615.973162] Call Trace: [ 615.975760] dump_stack+0x194/0x257 [ 615.979362] ? arch_local_irq_restore+0x53/0x53 [ 615.984008] nmi_cpu_backtrace+0x20e/0x240 [ 615.988214] ? kobject_synth_uevent+0xad0/0xad0 [ 615.992849] ? debug_check_no_locks_held+0x140/0x140 [ 615.997930] ? show_regs_print_info+0x65/0x65 [ 616.002399] ? irq_force_complete_move+0x390/0x390 [ 616.007296] nmi_trigger_cpumask_backtrace+0x122/0x180 [ 616.012545] arch_trigger_cpumask_backtrace+0x14/0x20 [ 616.017704] watchdog+0x90c/0xd60 [ 616.021146] ? reset_hung_task_detector+0xa0/0xa0 [ 616.025969] ? complete+0x62/0x80 [ 616.029399] ? __schedule+0x2070/0x2070 [ 616.033348] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 616.038420] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 616.043403] ? trace_hardirqs_on+0xd/0x10 [ 616.047528] ? __kthread_parkme+0x173/0x240 [ 616.051829] kthread+0x35e/0x430 [ 616.055170] ? reset_hung_task_detector+0xa0/0xa0 [ 616.059987] ? kthread_create_on_node+0x100/0x100 [ 616.064802] ret_from_fork+0x2a/0x40 [ 616.068543] Sending NMI from CPU 1 to CPUs 0: [ 616.073043] NMI backtrace for cpu 0 [ 616.073048] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.13.0-rc6+ #23 [ 616.073050] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 616.073053] task: ffffffff85a2c340 task.stack: ffffffff85a00000 [ 616.073060] RIP: 0010:lock_is_held_type+0x18b/0x210 [ 616.073061] RSP: 0018:ffff8801db207620 EFLAGS: 00000086 [ 616.073065] RAX: dffffc0000000000 RBX: 0000000000000086 RCX: 1ffff1003b664c1e [ 616.073067] RDX: 1ffffffff0b59431 RSI: ffff8801db325798 RDI: 0000000000000086 [ 616.073069] RBP: ffff8801db207640 R08: ffff88021fff901c R09: ffff88021fff9008 [ 616.073071] R10: ffff88021fff9010 R11: ffff88021fff901d R12: ffffffff85a2c340 [ 616.073073] R13: 0000000000000001 R14: 00000000000007ff R15: ffff8801db207988 [ 616.073076] FS: 0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 [ 616.073078] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 616.073080] CR2: 000055d7307e10d0 CR3: 00000001ce66f000 CR4: 00000000001406f0 [ 616.073084] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 616.073086] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 616.073087] Call Trace: [ 616.073088] [ 616.073094] ? update_rq_clock+0xc3/0x180 [ 616.073100] load_balance+0x1ac8/0x3eb0 [ 616.073103] ? check_noncircular+0x20/0x20 [ 616.073107] ? print_usage_bug+0x480/0x480 [ 616.073113] ? find_busiest_group+0x1d40/0x1d40 [ 616.073127] ? __rb_erase_color+0x27b0/0x27b0 [ 616.073131] ? trigger_load_balance+0x3a9/0x11b0 [ 616.073135] ? check_noncircular+0x20/0x20 [ 616.073138] ? print_usage_bug+0x480/0x480 [ 616.073143] ? run_posix_cpu_timers+0x1c8/0x18d0 [ 616.073147] ? __lock_is_held+0xb6/0x140 [ 616.073152] ? check_noncircular+0x20/0x20 [ 616.073154] ? check_noncircular+0x20/0x20 [ 616.073158] ? lock_acquire+0x1d5/0x580 [ 616.073161] ? lock_acquire+0x1d5/0x580 [ 616.073164] ? rebalance_domains+0x126/0xcc0 [ 616.073178] rebalance_domains+0x786/0xcc0 [ 616.073184] ? pick_next_task_fair+0x1610/0x1610 [ 616.073188] ? pick_next_task_fair+0x1610/0x1610 [ 616.073191] ? print_usage_bug+0x480/0x480 [ 616.073194] ? timerqueue_add+0x1e9/0x280 [ 616.073200] ? enqueue_hrtimer+0x162/0x490 [ 616.073203] ? __remove_hrtimer+0x190/0x190 [ 616.073209] ? _find_next_bit+0xee/0x120 [ 616.073214] run_rebalance_domains+0x39d/0x7c0 [ 616.073219] ? rebalance_domains+0xcc0/0xcc0 [ 616.073223] ? find_held_lock+0x35/0x1d0 [ 616.073228] ? rcu_pm_notify+0xc0/0xc0 [ 616.073274] __do_softirq+0x2f5/0xba3 [ 616.073281] ? __softirqentry_text_start+0x8/0x8 [ 616.073286] ? rcu_pm_notify+0xc0/0xc0 [ 616.073291] ? rcu_read_lock_sched_held+0x108/0x120 [ 616.073296] ? raise_softirq_irqoff+0x276/0x320 [ 616.073299] ? irq_exit+0x200/0x200 [ 616.073303] ? sched_set_stop_task+0x2a0/0x2a0 [ 616.073308] irq_exit+0x1cc/0x200 [ 616.073310] scheduler_ipi+0x165/0x460 [ 616.073315] smp_reschedule_interrupt+0x61/0x80 [ 616.073319] reschedule_interrupt+0x93/0xa0 [ 616.073322] RIP: 0010:native_safe_halt+0x6/0x10 [ 616.073324] RSP: 0018:ffffffff85a07ce0 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff02 [ 616.073327] RAX: dffffc0000000000 RBX: 1ffffffff0b40f9f RCX: 0000000000000000 [ 616.073329] RDX: 1ffffffff0b59434 RSI: 0000000000000001 RDI: ffffffff85aca1a0 [ 616.073331] RBP: ffffffff85a07ce0 R08: ffffffff85810a80 R09: 0000000000000000 [ 616.073333] R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff85aca190