ip6_tunnel: ®c9A«÷ª0HÒ`Š xmit: Local address not yet configured! ip6_tunnel: ®c9A«÷ª0HÒ`Š xmit: Local address not yet configured! INFO: task kworker/u4:6:3793 blocked for more than 140 seconds. Not tainted 4.14.71+ #8 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:6 D25960 3793 2 0x80000000 Workqueue: netns cleanup_net Call Trace: schedule+0x7f/0x1b0 kernel/sched/core.c:3490 schedule_timeout+0x710/0xe60 kernel/time/timer.c:1721 do_wait_for_common kernel/sched/completion.c:91 [inline] __wait_for_common kernel/sched/completion.c:112 [inline] wait_for_common+0x3bc/0x4e0 kernel/sched/completion.c:123 _rcu_barrier+0x27b/0x3f0 kernel/rcu/tree.c:3594 netdev_run_todo+0x112/0x750 net/core/dev.c:7865 sit_exit_net+0x42f/0x600 net/ipv6/sit.c:1869 ops_exit_list.isra.3+0xa8/0x150 net/core/net_namespace.c:142 cleanup_net+0x3e9/0x880 net/core/net_namespace.c:483 process_one_work+0x86e/0x15c0 kernel/workqueue.c:2114 worker_thread+0xdc/0x1000 kernel/workqueue.c:2248 kthread+0x348/0x420 kernel/kthread.c:232 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:402 Showing all locks held in the system: 3 locks held by kworker/0:0/3: #0: ("events"){+.+.}, at: [] process_one_work+0x787/0x15c0 kernel/workqueue.c:2085 #1: ((&map->work)){+.+.}, at: [] process_one_work+0x7bf/0x15c0 kernel/workqueue.c:2089 #2: (rcu_preempt_state.barrier_mutex){+.+.}, at: [] _rcu_barrier+0x5b/0x3f0 kernel/rcu/tree.c:3529 1 lock held by khungtaskd/23: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x74/0x20f kernel/locking/lockdep.c:4541 2 locks held by getty/1754: #0: (&tty->ldisc_sem){++++}, at: [] tty_ldisc_ref_wait+0x20/0x80 drivers/tty/tty_ldisc.c:275 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1ff/0x15e0 drivers/tty/n_tty.c:2142 4 locks held by kworker/u4:6/3793: #0: ("%s""netns"){+.+.}, at: [] process_one_work+0x787/0x15c0 kernel/workqueue.c:2085 #1: (net_cleanup_work){+.+.}, at: [] process_one_work+0x7bf/0x15c0 kernel/workqueue.c:2089 #2: (net_mutex){+.+.}, at: [] cleanup_net+0x14c/0x880 net/core/net_namespace.c:449 #3: (rcu_preempt_state.barrier_mutex){+.+.}, at: [] _rcu_barrier+0x5b/0x3f0 kernel/rcu/tree.c:3529 2 locks held by syz-executor1/4495: #0: (&tty->ldisc_sem){++++}, at: [] tty_ldisc_ref_wait+0x20/0x80 drivers/tty/tty_ldisc.c:275 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1ff/0x15e0 drivers/tty/n_tty.c:2142 2 locks held by syz-executor1/8578: #0: (&tty->ldisc_sem){++++}, at: [] tty_ldisc_ref_wait+0x20/0x80 drivers/tty/tty_ldisc.c:275 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1ff/0x15e0 drivers/tty/n_tty.c:2142 1 lock held by syz-executor4/17320: #0: (rcu_preempt_state.barrier_mutex){+.+.}, at: [] _rcu_barrier+0x5b/0x3f0 kernel/rcu/tree.c:3529 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 23 Comm: khungtaskd Not tainted 4.14.71+ #8 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0xb9/0x11b lib/dump_stack.c:53 nmi_cpu_backtrace.cold.0+0x47/0x85 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x121/0x146 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:138 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:196 [inline] watchdog+0x574/0xa70 kernel/hung_task.c:252 kthread+0x348/0x420 kernel/kthread.c:232 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:402 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 17219 Comm: syz-executor1 Not tainted 4.14.71+ #8 task: ffff8801a9c1af00 task.stack: ffff8801c8050000 RIP: 0010:trace_hardirqs_off_caller+0x179/0x250 kernel/locking/lockdep.c:2962 RSP: 0018:ffff8801c8057ee0 EFLAGS: 00000046 RAX: 00000000791d6ba3 RBX: ffff8801a9c1af00 RCX: 0000000000000000 RDX: 1ffff100353836db RSI: 0000000000000000 RDI: ffff8801a9c1b6d8 RBP: ffff8801a9c1af00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffffa200007e R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007ff22f052700(0000) GS:ffff8801d7700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020010038 CR3: 000000019d866002 CR4: 00000000001606a0 DR0: 0000000020000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: trace_hardirqs_off_thunk+0x1a/0x1c entry_SYSCALL_64_after_hwframe+0x3a/0xb7 RIP: 0033:0x457679 RSP: 002b:00007ff22f051cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 000000000072bf08 RCX: 0000000000457679 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000072bf08 RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000072bf0c R13: 00007fffa10fa16f R14: 00007ff22f0529c0 R15: 0000000000000000 Code: e8 07 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e bb 00 00 00 8b 83 d8 07 00 00 <48> 8d bb f4 07 00 00 48 89 fa 48 c1 ea 03 8d 68 01 48 b8 00 00