------------[ cut here ]------------
WARNING: CPU: 0 PID: 10820 at net/ipv4/af_inet.c:167 inet_sock_destruct+0x5f6/0x7b0 net/ipv4/af_inet.c:167()
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 10820 Comm: kworker/0:3 Not tainted 4.4.114-g4e74e98 #5
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: sock_diag_events sock_diag_broadcast_destroy_work
 0000000000000000 cf6da41e20ee4d30 ffff8800b9547a28 ffffffff81d03d2d
 ffffffff83843a40 ffff8800b9547b00 ffffffff83cf55e0 0000000000000009
 00000000000000a7 ffff8800b9547af0 ffffffff8141acba 0000000041b58ab3
Call Trace:
 [<ffffffff81d03d2d>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d03d2d>] dump_stack+0xc1/0x124 lib/dump_stack.c:51
 [<ffffffff8141acba>] panic+0x1aa/0x388 kernel/panic.c:112
 [<ffffffff8112d8d5>] warn_slowpath_common+0x125/0x140 kernel/panic.c:455
 [<ffffffff8112db39>] warn_slowpath_null+0x29/0x30 kernel/panic.c:492
 [<ffffffff831d2606>] inet_sock_destruct+0x5f6/0x7b0 net/ipv4/af_inet.c:167
 [<ffffffff8345dc77>] l2tp_tunnel_destruct+0x357/0x5a0 net/l2tp/l2tp_core.c:1235
 [<ffffffff82dfc96a>] sk_destruct+0x4a/0x4c0 net/core/sock.c:1447
 [<ffffffff82e99b7e>] sock_diag_broadcast_destroy_work+0x25e/0x380 net/core/sock_diag.c:153
 [<ffffffff8117fd87>] process_one_work+0x7d7/0x16e0 kernel/workqueue.c:2064
 [<ffffffff81180d69>] worker_thread+0xd9/0xfc0 kernel/workqueue.c:2196
 [<ffffffff811907d8>] kthread+0x268/0x300 kernel/kthread.c:211
 [<ffffffff83774705>] ret_from_fork+0x55/0x80 arch/x86/entry/entry_64.S:506
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..