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-2,10.128.15.209' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 615.392145] INFO: task syzkaller445118:3011 blocked for more than 120 seconds. [ 615.393410] Not tainted 4.13.0-rc6+ #23 [ 615.394397] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 615.395553] syzkaller445118 D24384 3011 3005 0x00000004 [ 615.396405] Call Trace: [ 615.396943] __schedule+0x8e8/0x2070 [ 615.397496] ? __sched_text_start+0x8/0x8 [ 615.398210] ? check_noncircular+0x20/0x20 [ 615.398814] ? trace_hardirqs_on_caller+0x19e/0x5c0 [ 615.399640] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 615.400346] ? retint_kernel+0x10/0x10 [ 615.401118] schedule+0x108/0x440 [ 615.401595] ? lock_downgrade+0x990/0x990 [ 615.402175] ? __schedule+0x2070/0x2070 [ 615.402810] ? __update_idle_core+0x311/0x610 [ 615.403555] ? mark_held_locks+0xaf/0x100 [ 615.404191] ? __local_bh_enable_ip+0x9d/0x160 [ 615.404847] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 615.405612] ? __lock_sock+0x1d7/0x2f0 [ 615.406193] ? trace_hardirqs_on+0xd/0x10 [ 615.406841] ? __local_bh_enable_ip+0x9d/0x160 [ 615.407577] __lock_sock+0x1dc/0x2f0 [ 615.408106] ? proto_unregister+0x5e0/0x5e0 [ 615.408687] ? finish_wait+0x490/0x490 [ 615.409236] ? lock_sock_nested+0x44/0x110 [ 615.409815] lock_sock_nested+0xf3/0x110 [ 615.410515] tcp_sendmsg+0x21/0x50 [ 615.411114] inet_sendmsg+0x11f/0x5e0 [ 615.411657] ? inet_recvmsg+0x5f0/0x5f0 [ 615.412316] ? selinux_socket_sendmsg+0x36/0x40 [ 615.417047] ? security_socket_sendmsg+0x89/0xb0 [ 615.421874] ? inet_recvmsg+0x5f0/0x5f0 [ 615.425981] sock_sendmsg+0xca/0x110 [ 615.429784] kernel_sendmsg+0x47/0x60 [ 615.433658] sock_no_sendpage+0x1cc/0x280 [ 615.437857] ? sock_kzfree_s+0x60/0x60 [ 615.441819] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 615.446915] tcp_sendpage_locked+0x10b/0x160 [ 615.451389] tcp_sendpage+0x43/0x60 [ 615.455073] ? tcp_sendpage_locked+0x160/0x160 [ 615.459692] inet_sendpage+0x1aa/0x660 [ 615.463648] ? inet_sendmsg+0x5e0/0x5e0 [ 615.467675] ? inet_sendmsg+0x5e0/0x5e0 [ 615.471722] kernel_sendpage+0x8d/0xe0 [ 615.475693] sock_sendpage+0x8c/0xc0 [ 615.479494] ? kernel_sendpage+0xe0/0xe0 [ 615.483718] pipe_to_sendpage+0x290/0x3b0 [ 615.487935] ? direct_splice_actor+0x180/0x180 [ 615.492579] ? splice_from_pipe_next.part.9+0x22a/0x2e0 [ 615.498058] __splice_from_pipe+0x343/0x750 [ 615.502475] ? direct_splice_actor+0x180/0x180 [ 615.507159] splice_from_pipe+0x1e9/0x330 [ 615.511363] ? direct_splice_actor+0x180/0x180 [ 615.516100] ? splice_shrink_spd+0xb0/0xb0 [ 615.520416] ? security_file_permission+0x89/0x1e0 [ 615.525374] generic_splice_sendpage+0x40/0x50 [ 615.529965] ? splice_from_pipe+0x330/0x330 [ 615.534312] SyS_splice+0x7b7/0x1610 [ 615.538054] ? compat_SyS_vmsplice+0x250/0x250 [ 615.542647] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 615.547673] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 615.552457] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 615.557217] RIP: 0033:0x445469 [ 615.560416] RSP: 002b:00007f04dcc9adb8 EFLAGS: 00000212 ORIG_RAX: 0000000000000113 [ 615.568142] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000445469 [ 615.575423] RDX: 0000000000000005 RSI: 0000000000000000 RDI: 0000000000000003 [ 615.582706] RBP: 0000000000000086 R08: 000000000000001f R09: 0000000000000000 [ 615.589993] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000000 [ 615.597279] R13: 00007ffd2150e3bf R14: 00007f04dcc9b9c0 R15: 0000000000000000 [ 615.604585] [ 615.604585] Showing all locks held in the system: [ 615.610915] 2 locks held by khungtaskd/637: [ 615.615267] #0: (rcu_read_lock){......}, at: [] watchdog+0x1c5/0xd60 [ 615.623601] #1: (tasklist_lock){.+.+..}, at: [] debug_show_all_locks+0xd2/0x410 [ 615.632836] 2 locks held by getty/2978: [ 615.636830] #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x37/0x40 [ 615.645698] #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x2ef/0x1a40 [ 615.655229] 2 locks held by getty/2979: [ 615.659215] #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x37/0x40 [ 615.668072] #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x2ef/0x1a40 [ 615.677542] 2 locks held by getty/2980: [ 615.681525] #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x37/0x40 [ 615.690398] #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x2ef/0x1a40 [ 615.699869] 2 locks held by getty/2981: [ 615.703849] #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x37/0x40 [ 615.712746] #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x2ef/0x1a40 [ 615.722226] 2 locks held by getty/2982: [ 615.726202] #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x37/0x40 [ 615.735074] #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x2ef/0x1a40 [ 615.744538] 2 locks held by getty/2983: [ 615.748520] #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x37/0x40 [ 615.757374] #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x2ef/0x1a40 [ 615.766842] 2 locks held by getty/2984: [ 615.770821] #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x37/0x40 [ 615.779713] #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x2ef/0x1a40 [ 615.789201] 2 locks held by syzkaller445118/3011: [ 615.794063] #0: (&pipe->mutex/1){+.+.+.}, at: [] pipe_wait+0x1e6/0x280 [ 615.802551] #1: (sk_lock-AF_INET){+.+.+.}, at: [] tcp_sendpage+0x2e/0x60 [ 615.811153] [ 615.812770] ============================================= [ 615.812770] [ 615.819810] NMI backtrace for cpu 1 [ 615.823448] CPU: 1 PID: 637 Comm: khungtaskd Not tainted 4.13.0-rc6+ #23 [ 615.830256] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 615.839581] Call Trace: [ 615.842186] dump_stack+0x194/0x257 [ 615.845794] ? arch_local_irq_restore+0x53/0x53 [ 615.850442] nmi_cpu_backtrace+0x20e/0x240 [ 615.854644] ? kobject_synth_uevent+0xad0/0xad0 [ 615.859278] ? debug_check_no_locks_held+0x140/0x140 [ 615.864373] ? show_regs_print_info+0x65/0x65 [ 615.868862] ? irq_force_complete_move+0x390/0x390 [ 615.873757] nmi_trigger_cpumask_backtrace+0x122/0x180 [ 615.879003] arch_trigger_cpumask_backtrace+0x14/0x20 [ 615.884160] watchdog+0x90c/0xd60 [ 615.887592] ? reset_hung_task_detector+0xa0/0xa0 [ 615.892404] ? complete+0x62/0x80 [ 615.895834] ? __schedule+0x2070/0x2070 [ 615.899781] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 615.904854] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 615.909836] ? trace_hardirqs_on+0xd/0x10 [ 615.913992] ? __kthread_parkme+0x173/0x240 [ 615.918287] kthread+0x35e/0x430 [ 615.921623] ? reset_hung_task_detector+0xa0/0xa0 [ 615.926431] ? kthread_create_on_node+0x100/0x100 [ 615.931242] ret_from_fork+0x2a/0x40 [ 615.935037] Sending NMI from CPU 1 to CPUs 0: [ 615.939546] NMI backtrace for cpu 0 skipped: idling at pc 0xffffffff84d73a36 [ 615.940539] Kernel panic - not syncing: hung_task: blocked tasks [ 615.940545] CPU: 1 PID: 637 Comm: khungtaskd Not tainted 4.13.0-rc6+ #23 [ 615.940547] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 615.940549] Call Trace: [ 615.940557] dump_stack+0x194/0x257 [ 615.940564] ? arch_local_irq_restore+0x53/0x53 [ 615.940601] panic+0x1e4/0x417 [ 615.940606] ? __warn+0x1d9/0x1d9 [ 615.940626] watchdog+0x91d/0xd60 [ 615.940642] ? reset_hung_task_detector+0xa0/0xa0 [ 615.940648] ? complete+0x62/0x80 [ 615.940663] ? __schedule+0x2070/0x2070 [ 615.940675] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 615.940681] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 615.940687] ? trace_hardirqs_on+0xd/0x10 [ 615.940691] ? __kthread_parkme+0x173/0x240 [ 615.940701] kthread+0x35e/0x430 [ 615.940705] ? reset_hung_task_detector+0xa0/0xa0 [ 615.940709] ? kthread_create_on_node+0x100/0x100 [ 615.940716] ret_from_fork+0x2a/0x40 [ 616.037037] Dumping ftrace buffer: [ 616.040705] (ftrace buffer empty) [ 616.044393] Kernel Offset: disabled [ 616.047996] Rebooting in 86400 seconds..