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-next-kasan-gce-6,10.128.0.10' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 615.392161] INFO: task syzkaller711065:3050 blocked for more than 120 seconds. [ 615.399699] Not tainted 4.13.0-rc6-next-20170825+ #9 [ 615.405515] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 615.413487] syzkaller711065 D22912 3050 3048 0x00000000 [ 615.419169] Call Trace: [ 615.421796] __schedule+0x8e8/0x2070 [ 615.425528] ? __sched_text_start+0x8/0x8 [ 615.429691] ? prepare_to_wait_exclusive+0xb6/0x530 [ 615.434734] ? find_held_lock+0x39/0x1d0 [ 615.438817] ? trace_hardirqs_on_caller+0x19e/0x5c0 [ 615.443856] ? trace_hardirqs_on+0xd/0x10 [ 615.448041] schedule+0x108/0x440 [ 615.451500] ? __schedule+0x2070/0x2070 [ 615.455477] ? mark_held_locks+0xb2/0x100 [ 615.459648] ? __local_bh_enable_ip+0x9d/0x160 [ 615.464235] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 615.469268] ? __lock_sock+0x1d7/0x2f0 [ 615.473156] ? trace_hardirqs_on+0xd/0x10 [ 615.477307] ? __local_bh_enable_ip+0x9d/0x160 [ 615.481890] __lock_sock+0x1dc/0x2f0 [ 615.485613] ? proto_unregister+0x5e0/0x5e0 [ 615.489936] ? finish_wait+0x490/0x490 [ 615.493827] ? lock_sock_nested+0x44/0x110 [ 615.498070] lock_sock_nested+0xf3/0x110 [ 615.502159] tcp_sendmsg+0x21/0x50 [ 615.505748] inet_sendmsg+0x11f/0x5e0 [ 615.509564] ? inet_recvmsg+0x5f0/0x5f0 [ 615.513539] ? selinux_socket_sendmsg+0x36/0x40 [ 615.518216] ? security_socket_sendmsg+0x89/0xb0 [ 615.522970] ? inet_recvmsg+0x5f0/0x5f0 [ 615.526959] sock_sendmsg+0xca/0x110 [ 615.530672] kernel_sendmsg+0x47/0x60 [ 615.534480] sock_no_sendpage+0x1cc/0x280 [ 615.538645] ? sock_no_shutdown+0x10/0x10 [ 615.542824] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 615.547844] tcp_sendpage_locked+0x10b/0x160 [ 615.552266] tcp_sendpage+0x43/0x60 [ 615.555892] ? tcp_sendpage_locked+0x160/0x160 [ 615.560481] inet_sendpage+0x1aa/0x660 [ 615.564374] ? inet_sendmsg+0x5e0/0x5e0 [ 615.568366] ? inet_sendmsg+0x5e0/0x5e0 [ 615.572345] kernel_sendpage+0x8d/0xe0 [ 615.576254] sock_sendpage+0x92/0xc0 [ 615.579971] ? kernel_sendpage+0xe0/0xe0 [ 615.584040] pipe_to_sendpage+0x290/0x3b0 [ 615.588190] ? direct_splice_actor+0x180/0x180 [ 615.592778] ? check_same_owner+0x320/0x320 [ 615.597094] ? splice_from_pipe_next.part.9+0x22a/0x2e0 [ 615.602471] __splice_from_pipe+0x343/0x750 [ 615.606793] ? direct_splice_actor+0x180/0x180 [ 615.611384] splice_from_pipe+0x1e9/0x330 [ 615.615529] ? direct_splice_actor+0x180/0x180 [ 615.620112] ? splice_shrink_spd+0xb0/0xb0 [ 615.624353] ? security_file_permission+0x89/0x1f0 [ 615.629291] generic_splice_sendpage+0x40/0x50 [ 615.633866] ? splice_from_pipe+0x330/0x330 [ 615.638192] SyS_splice+0x7d5/0x1630 [ 615.641914] ? vmacache_find+0x61/0x270 [ 615.645912] ? compat_SyS_vmsplice+0x250/0x250 [ 615.650491] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 615.655514] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 615.660321] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 615.665097] RIP: 0033:0x43fd59 [ 615.668284] RSP: 002b:00007ffe02bcff08 EFLAGS: 00000216 ORIG_RAX: 0000000000000113 [ 615.676019] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fd59 [ 615.683295] RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000004 [ 615.690579] RBP: 0000000000000086 R08: 0000000810000004 R09: 000000000000000a [ 615.697851] R10: 0000000000000000 R11: 0000000000000216 R12: 00000000004016c0 [ 615.705149] R13: 0000000000401750 R14: 0000000000000000 R15: 0000000000000000 [ 615.712435] [ 615.712435] Showing all locks held in the system: [ 615.718765] 2 locks held by khungtaskd/644: [ 615.723107] #0: (rcu_read_lock){....}, at: [] watchdog+0x1c5/0xd60 [ 615.731204] #1: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0xd2/0x410 [ 615.740254] 1 lock held by rsyslogd/2936: [ 615.744406] #0: (&f->f_pos_lock){+.+.}, at: [] __fdget_pos+0x131/0x1a0 [ 615.752832] 2 locks held by getty/3018: [ 615.756807] #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x37/0x40 [ 615.765499] #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x2f2/0x1a40 [ 615.774806] 2 locks held by getty/3019: [ 615.778783] #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x37/0x40 [ 615.787482] #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x2f2/0x1a40 [ 615.796879] 2 locks held by getty/3020: [ 615.800858] #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x37/0x40 [ 615.809544] #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x2f2/0x1a40 [ 615.818845] 2 locks held by getty/3021: [ 615.822811] #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x37/0x40 [ 615.831504] #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x2f2/0x1a40 [ 615.840804] 2 locks held by getty/3022: [ 615.844782] #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x37/0x40 [ 615.853475] #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x2f2/0x1a40 [ 615.862786] 2 locks held by getty/3023: [ 615.866753] #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x37/0x40 [ 615.875451] #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x2f2/0x1a40 [ 615.884751] 2 locks held by getty/3024: [ 615.888733] #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x37/0x40 [ 615.897428] #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x2f2/0x1a40 [ 615.906742] 2 locks held by syzkaller711065/3050: [ 615.911577] #0: (&pipe->mutex/1){+.+.}, at: [] pipe_lock+0x56/0x70 [ 615.919693] #1: (sk_lock-AF_INET){+.+.}, at: [] tcp_sendpage+0x2e/0x60 [ 615.928122] [ 615.929752] ============================================= [ 615.929752] [ 615.936774] NMI backtrace for cpu 0 [ 615.940418] CPU: 0 PID: 644 Comm: khungtaskd Not tainted 4.13.0-rc6-next-20170825+ #9 [ 615.948353] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 615.957678] Call Trace: [ 615.960280] dump_stack+0x194/0x257 [ 615.963882] ? arch_local_irq_restore+0x53/0x53 [ 615.968536] nmi_cpu_backtrace+0x20e/0x240 [ 615.972744] ? kobject_synth_uevent+0xad0/0xad0 [ 615.977386] ? debug_check_no_locks_held+0x140/0x140 [ 615.982462] ? show_regs_print_info+0x65/0x65 [ 615.986937] ? irq_force_complete_move+0x390/0x390 [ 615.991852] nmi_trigger_cpumask_backtrace+0x122/0x180 [ 615.997103] arch_trigger_cpumask_backtrace+0x14/0x20 [ 616.002269] watchdog+0x90c/0xd60 [ 616.005705] ? reset_hung_task_detector+0xa0/0xa0 [ 616.010531] ? __schedule+0x2070/0x2070 [ 616.014479] ? retint_kernel+0x10/0x10 [ 616.018362] ? __kthread_parkme+0x173/0x240 [ 616.022662] kthread+0x39c/0x470 [ 616.025999] ? reset_hung_task_detector+0xa0/0xa0 [ 616.030811] ? kthread_create_on_node+0x100/0x100 [ 616.035633] ret_from_fork+0x2a/0x40 [ 616.039404] Sending NMI from CPU 0 to CPUs 1: [ 616.043901] NMI backtrace for cpu 1 skipped: idling at pc 0xffffffff84da2b86 [ 616.044904] Kernel panic - not syncing: hung_task: blocked tasks [ 616.044910] CPU: 0 PID: 644 Comm: khungtaskd Not tainted 4.13.0-rc6-next-20170825+ #9 [ 616.044914] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 616.044917] Call Trace: [ 616.044926] dump_stack+0x194/0x257 [ 616.044935] ? arch_local_irq_restore+0x53/0x53 [ 616.044954] panic+0x1e4/0x41c [ 616.044961] ? refcount_error_report+0x214/0x214 [ 616.044984] watchdog+0x91d/0xd60 [ 616.045004] ? reset_hung_task_detector+0xa0/0xa0 [ 616.045022] ? __schedule+0x2070/0x2070 [ 616.045027] ? retint_kernel+0x10/0x10 [ 616.045049] ? __kthread_parkme+0x173/0x240 [ 616.045060] kthread+0x39c/0x470 [ 616.045065] ? reset_hung_task_detector+0xa0/0xa0 [ 616.045070] ? kthread_create_on_node+0x100/0x100 [ 616.045079] ret_from_fork+0x2a/0x40 [ 616.130061] Dumping ftrace buffer: [ 616.133707] (ftrace buffer empty) [ 616.137396] Kernel Offset: disabled [ 616.141007] Rebooting in 86400 seconds..