INFO: task kworker/0:5:30407 blocked for more than 140 seconds.
      Not tainted 4.9.125+ #37
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/0:5     D29432 30407      2 0x00000000
Workqueue: ipv6_addrconf addrconf_verify_work
 ffff8801a5deaf80 ffff8801d13c9600 ffff8801d13c9600 ffff88019d705f00
 ffff8801db621018 ffff8801ba5c7ae8 ffffffff8277d092 0000000000000002
 ffff8801a5deb830 ffffed0034bbd705 00ff8801a5deaf80 ffff8801db6218f0
Call Trace:
 [<ffffffff8277e5bf>] schedule+0x7f/0x1b0 kernel/sched/core.c:3553
 [<ffffffff8277ef43>] schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3586
 [<ffffffff82780bc6>] __mutex_lock_common kernel/locking/mutex.c:582 [inline]
 [<ffffffff82780bc6>] mutex_lock_nested+0x326/0x870 kernel/locking/mutex.c:621
 [<ffffffff822c12d7>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70
 [<ffffffff82639a1e>] addrconf_verify_work+0xe/0x20 net/ipv6/addrconf.c:4366
 [<ffffffff8112c511>] process_one_work+0x791/0x1470 kernel/workqueue.c:2092
 [<ffffffff8112d2c6>] worker_thread+0xd6/0x10a0 kernel/workqueue.c:2226
 [<ffffffff8113d9ad>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff8278c35c>] 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: [<ffffffff81309abc>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff81309abc>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff813e68fc>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
1 lock held by rsyslogd/2125:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff8154c11c>] __fdget_pos+0xac/0xd0 fs/file.c:781
2 locks held by getty/2252:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff8278a262>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff81cdd442>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142
3 locks held by kworker/0:5/30407:
 #0:  ("%s"("ipv6_addrconf")){.+.+..}, at: [<ffffffff8112c420>] process_one_work+0x6a0/0x1470 kernel/workqueue.c:2085
 #1:  ((addr_chk_work).work){+.+...}, at: [<ffffffff8112c458>] process_one_work+0x6d8/0x1470 kernel/workqueue.c:2089
 #2:  (rtnl_mutex){+.+.+.}, at: [<ffffffff822c12d7>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70
3 locks held by kworker/1:5/32548:
 #0:  ("events"){.+.+.+}, at: [<ffffffff8112c420>] process_one_work+0x6a0/0x1470 kernel/workqueue.c:2085
 #1:  ((linkwatch_work).work){+.+...}, at: [<ffffffff8112c458>] process_one_work+0x6d8/0x1470 kernel/workqueue.c:2089
 #2:  (rtnl_mutex){+.+.+.}, at: [<ffffffff822c12d7>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 24 Comm: khungtaskd Not tainted 4.9.125+ #37
 ffff8801d94a7d08 ffffffff81af0ae9 0000000000000000 0000000000000001
 0000000000000001 0000000000000001 ffffffff810967d0 ffff8801d94a7d40
 ffffffff81afb849 0000000000000001 0000000000000000 0000000000000003
Call Trace:
 [<ffffffff81af0ae9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81af0ae9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81afb849>] nmi_cpu_backtrace.cold.0+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81afb7dc>] nmi_trigger_cpumask_backtrace+0x12c/0x151 lib/nmi_backtrace.c:60
 [<ffffffff810968d4>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff8130a04d>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff8130a04d>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff8130a04d>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff8130a04d>] watchdog+0x6ad/0xa20 kernel/hung_task.c:239
 [<ffffffff8113d9ad>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff8278c35c>] 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: 22905 Comm: syz-executor5 Not tainted 4.9.125+ #37
task: ffff88019d705f00 task.stack: ffff8801b7438000
RIP: 0010:[<ffffffff811feb06>] 
c [<ffffffff811feb06>] arch_local_save_flags arch/x86/include/asm/paravirt.h:763 [inline]
RIP: 0010:[<ffffffff811feb06>] 
c [<ffffffff811feb06>] trace_hardirqs_on_caller+0x116/0x590 kernel/locking/lockdep.c:2719
RSP: 0018:ffff8801b743fec8  EFLAGS: 00000046
RAX: 0000000000000003 RBX: ffffffff83fe9840 RCX: 0000000000457099
RDX: 0000000000000004 RSI: ffffffff810053cb RDI: ffff88019d706778
RBP: ffff8801b743fee0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff810053f8
R13: ffff8801b743ffd0 R14: ffff88019d705f00 R15: 0000000000000000
FS:  00007fd59c377700(0000) GS:ffff8801db600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd77c318000 CR3: 00000001a6866000 CR4: 00000000001606b0
DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Stack:
 0000000000000046
c ffff8801b743ff58
c 00000000000000ca
c ffff8801b743fef0
c
 ffffffff811fef8d
c ffff8801b743ff48
c ffffffff810053f8
c 0000000000000000
c
 0000000000000000
c 0000000000000000
c 0000000000000000
c 0000000000000000
c
Call Trace:
 [<ffffffff811fef8d>] trace_hardirqs_on+0xd/0x10 kernel/locking/lockdep.c:2743
 [<ffffffff810053f8>] do_syscall_64+0x48/0x480 arch/x86/entry/common.c:270
 [<ffffffff8278c193>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Code: 
c03 
c0f 
cb6 
c14 
c02 
c48 
c89 
cd8 
c83 
ce0 
c07 
c83 
cc0 
c03 
c38 
cd0 
c7c 
c08 
c84 
cd2 
c0f 
c85 
c2a 
c03 
c00 
c00 
c44 
c8b 
c0d 
c44 
cad 
cde 
c02 
c45 
c85 
cc9 
c0f 
c85 
cc8 
c00 
c00 
c00 
c9c 
c<58> 
c0f 
c1f 
c44 
c00 
c00 
cf6 
cc4 
c02 
c0f 
c85 
c5a 
c03 
c00 
c00 
c48 
cb8 
c00 
c00 
c00 
c00 
c