ip6_tunnel: ip6tnl1 xmit: Local address not yet configured! ip6_tunnel: ip6tnl1 xmit: Local address not yet configured! BUG: workqueue lockup - pool[ 1289.448298] INFO: task kworker/u4:10:7189 blocked for more than 140 seconds. Not tainted 4.9.168+ #39 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:10 D 26248 7189 2 0x80000000 Workqueue: netns cleanup_net ffff8801c7af17c0 ffff8801a357b700 ffff8801db721000 ffff88016c0297c0 ffff8801db721018 ffff88019f957480 ffffffff8280028e 0000000000000000 00000000000001ac 0000000000000005 ffff8801db7218f0 1ffff10033f2ae7fCall Trace: [<00000000e1ddfd65>] schedule+0x92/0x1c0 kernel/sched/core.c:3546 [<000000000ec08ca0>] schedule_timeout+0x766/0xe50 kernel/time/timer.c:1771 [<00000000ee3aa89a>] do_wait_for_common kernel/sched/completion.c:75 [inline] [<00000000ee3aa89a>] __wait_for_common kernel/sched/completion.c:93 [inline] [<00000000ee3aa89a>] wait_for_common+0x2c6/0x4d0 kernel/sched/completion.c:101 [<0000000079e9a1d4>] wait_for_completion+0x18/0x20 kernel/sched/completion.c:122 [<00000000461098a8>] flush_work+0x3d2/0x720 kernel/workqueue.c:2877 [<00000000ded11430>] flush_all_backlogs net/core/dev.c:4427 [inline] [<00000000ded11430>] rollback_registered_many+0x57a/0xb50 net/core/dev.c:6846 [<000000000a8044e3>] unregister_netdevice_many.part.0+0x1b/0x1e0 net/core/dev.c:7907 [<000000005f71c3e4>] unregister_netdevice_many+0x3b/0x50 net/core/dev.c:7906 [<000000006e5bbb04>] ip6_tnl_destroy_tunnels net/ipv6/ip6_tunnel.c:2193 [inline] [<000000006e5bbb04>] ip6_tnl_exit_net+0x3e8/0x5b0 net/ipv6/ip6_tunnel.c:2240 [<00000000bdbd2dc9>] ops_exit_list.isra.0+0xb0/0x160 net/core/net_namespace.c:136 [<000000000ea9f435>] cleanup_net+0x3d6/0x8a0 net/core/net_namespace.c:473 [<000000007a225d68>] process_one_work+0x88b/0x1600 kernel/workqueue.c:2114 [<000000003b2d72fe>] worker_thread+0x5df/0x11d0 kernel/workqueue.c:2251 [<000000007fa774b4>] kthread+0x278/0x310 kernel/kthread.c:211 [<0000000031e5143e>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373 Showing all locks held in the system: 2 locks held by khungtaskd/24: #0: (rcu_read_lock){......}, at: [<0000000034e6c5eb>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline] (rcu_read_lock){......}, at: [<0000000034e6c5eb>] watchdog+0x13c/0xae0 kernel/hung_task.c:239 (tasklist_lock){.+.+..}, at: [<00000000bfb336a8>] debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4339 #0: (&f->f_pos_lock){+.+.+.}, at: [<00000000dc1add48>] __fdget_pos+0xa8/0xd0 fs/file.c:782 #0: (&tty->ldisc_sem){++++++}, at: [<0000000071c93765>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377 (&ldata->atomic_read_lock){+.+...}, at: [<000000007f0c186a>] n_tty_read+0x1fe/0x1820 drivers/tty/n_tty.c:2156 #0: ("%s""netns"){.+.+.+}, at: [<0000000091b1bfa0>] process_one_work+0x790/0x1600 kernel/workqueue.c:2107 (net_cleanup_work){+.+.+.}, at: [<000000009aa7059e>] process_one_work+0x7ce/0x1600 kernel/workqueue.c:2111 (net_mutex){+.+.+.}, at: [<0000000087f02f9a>] cleanup_net+0x131/0x8a0 net/core/net_namespace.c:439 (rtnl_mutex){+.+.+.}, at: [<00000000ef5b3c78>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70 (cpu_hotplug.dep_map){++++++}, at: [<0000000047c259f4>] get_online_cpus+0x32/0x90 kernel/cpu.c:253 #0: (&sb->s_type->i_mutex_key#8){+.+.+.}, at: [<000000007f2107de>] inode_lock include/linux/fs.h:768 [inline] (&sb->s_type->i_mutex_key#8){+.+.+.}, at: [<000000007f2107de>] __sock_release+0x89/0x2c0 net/socket.c:604 (rtnl_mutex){+.+.+.}, at: [<00000000ef5b3c78>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70 #0: (lock#2){+.+...}, at: [<00000000b89506f6>] lru_add_drain_all+0x34/0x3e0 mm/swap.c:696 (cpu_hotplug.dep_map){++++++}, at: [<0000000047c259f4>] get_online_cpus+0x32/0x90 kernel/cpu.c:253 #0: (net_mutex){+.+.+.}, at: [<00000000ccbc8176>] copy_net_ns+0x15b/0x340 net/core/net_namespace.c:406 #0: ("%s"("ipv6_addrconf")){.+.+..}, at: [<0000000091b1bfa0>] process_one_work+0x790/0x1600 kernel/workqueue.c:2107 ((addr_chk_work).work){+.+...}, at: [<000000009aa7059e>] process_one_work+0x7ce/0x1600 kernel/workqueue.c:2111 (rtnl_mutex){+.+.+.}, at: [<00000000ef5b3c78>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 24 Comm: khungtaskd Not tainted 4.9.168+ #39 ffff8801d98d7cc8 ffffffff81b4f5d1 0000000000000001 0000000000000000 0000000000000001 ffffffff81097401 dffffc0000000000 ffff8801d98d7d00 ffffffff81b5a86c 0000000000000001 0000000000000000 0000000000000001Call Trace: [<00000000c9ea56db>] __dump_stack lib/dump_stack.c:15 [inline] [<00000000c9ea56db>] dump_stack+0xc1/0x120 lib/dump_stack.c:51 [<000000002e2048f5>] nmi_cpu_backtrace.cold+0x47/0x87 lib/nmi_backtrace.c:99 [<000000009cfb528b>] nmi_trigger_cpumask_backtrace+0x124/0x155 lib/nmi_backtrace.c:60 [<00000000ba05645e>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37 [<000000002ee72921>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline] [<000000002ee72921>] check_hung_task kernel/hung_task.c:125 [inline] [<000000002ee72921>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline] [<000000002ee72921>] watchdog+0x661/0xae0 kernel/hung_task.c:239 [<000000007fa774b4>] kthread+0x278/0x310 kernel/kthread.c:211 [<0000000031e5143e>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 12395 Comm: syz-executor.4 Not tainted 4.9.168+ #39 task: 00000000df40ff21 task.stack: 00000000c58184b2 RIP: 0010:[] c [<00000000533bc991>] io_serial_in+0x6b/0x90 drivers/tty/serial/8250/8250_port.c:414 RSP: 0000:ffff8801db6077b0 EFLAGS: 00000002 RAX: dffffc0000000020 RBX: 00000000000003fd RCX: 0000000000000000 RDX: 00000000000003fd RSI: ffffffff81d6ef71 RDI: ffffffff84b61a98 RBP: ffff8801db6077c0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: ffffffff841d036a R12: ffffffff84b61a60 R13: 0000000000000020 R14: fffffbfff096c393 R15: fffffbfff096c355 FS: 00007fac71c7f700(0000) GS:ffff8801db600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fac71c3cdb8 CR3: 000000016c96f000 CR4: 00000000001606b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Stack: ffffffff84b61a60c 0000000000002706c ffff8801db607810c ffffffff81d71214c 0000000000021000c ffffffff84b61aa8c ffffffff84b61c9ac ffffffff841d034fc ffffffff84b61a60c 0000000000000020c dffffc0000000000c 0000000000000020c Call Trace: d [<000000005cdc4fb2>] serial_in drivers/tty/serial/8250/8250.h:111 [inline] d [<000000005cdc4fb2>] wait_for_xmitr+0x94/0x1e0 drivers/tty/serial/8250/8250_port.c:1997 [<0000000062984141>] serial8250_console_putchar+0x20/0x60 drivers/tty/serial/8250/8250_port.c:3103 [<00000000f10ea938>] uart_console_write+0x56/0xe0 drivers/tty/serial/serial_core.c:1886 [<0000000000559b37>] serial8250_console_write+0x2fb/0x860 drivers/tty/serial/8250/8250_port.c:3169 [<000000000f3cec27>] univ8250_console_write+0x5f/0x70 drivers/tty/serial/8250/8250_core.c:594 [<00000000c90dff0c>] call_console_drivers.isra.0.constprop.0+0x1ac/0x360 kernel/printk/printk.c:1594 [<000000006686df30>] console_cont_flush kernel/printk/printk.c:2321 [inline] [<000000006686df30>] console_unlock+0x17b/0xb20 kernel/printk/printk.c:2387 [<00000000819056ac>] vprintk_emit+0x43f/0x6f0 kernel/printk/printk.c:1908 [<00000000e39a6199>] vprintk+0x28/0x30 kernel/printk/printk.c:1918 [<000000009f641e4c>] vprintk_func kernel/printk/internal.h:36 [inline] [<000000009f641e4c>] printk+0xc2/0xf5 kernel/printk/printk.c:1980 [<000000001eec66e9>] wq_watchdog_timer_fn.cold+0x11/0x66 kernel/workqueue.c:5432 [<00000000f68f9f5d>] call_timer_fn+0x167/0x6d0 kernel/time/timer.c:1319 [<000000005f60e37c>] expire_timers+0x25b/0x5c0 kernel/time/timer.c:1359 [<000000006be3df67>] __run_timers kernel/time/timer.c:1674 [inline] [<000000006be3df67>] run_timer_softirq+0x404/0x620 kernel/time/timer.c:1689 [<000000001aa9c046>] __do_softirq+0x22d/0x964 kernel/softirq.c:288 [<000000003580434b>] invoke_softirq kernel/softirq.c:368 [inline] [<000000003580434b>] irq_exit+0x119/0x160 kernel/softirq.c:409 [<00000000f602eb3a>] exiting_irq arch/x86/include/asm/apic.h:669 [inline] [<00000000f602eb3a>] smp_apic_timer_interrupt+0x7e/0xb0 arch/x86/kernel/apic/apic.c:962 [<00000000e0811311>] apic_timer_interrupt+0x9d/0xb0 arch/x86/entry/entry_64.S:648 dCode: c24 cc9 c00 c00 c00 c49 c8d c7c c24 c38 c48 cb8 c00 c00 c00 c00 c00 cfc cff cdf c48 c89 cfa c48 cc1 cea c03 cd3 ce3 c80 c3c c02 c00 c75 c17 c41 c03 c5c c24 c38 c89 cda cec c<5b> c0f cb6 cc0 c41 c5c c5d cc3 ce8 cb8 c9b c78 cff ceb cc2 ce8 c11 c9c c78 cff ceb c