------------[ cut here ]------------ WARNING: CPU: 1 PID: 17 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: 1 PID: 17 Comm: ksoftirqd/1 Not tainted 4.9.77-ge12a9c4 #18 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ffff8801d9827a40 ffffffff81d941c9 ffffffff83a47bc0 ffff8801d9827b18 ffffffff83f2f000 ffffffff832ebc36 0000000000000009 ffff8801d9827b08 ffffffff8142f3c1 0000000041b58ab3 ffffffff8418ab70 ffffffff8142f205 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x128 lib/dump_stack.c:51 [] panic+0x1bc/0x3a8 kernel/panic.c:179 [] __warn+0x1c4/0x1e0 kernel/panic.c:542 [] warn_slowpath_null+0x2c/0x40 kernel/panic.c:585 [] inet_sock_destruct+0x5f6/0x7b0 net/ipv4/af_inet.c:167 [] l2tp_tunnel_destruct+0x352/0x5a0 net/l2tp/l2tp_core.c:1329 [] __sk_destruct+0x53/0x570 net/core/sock.c:1428 [] __rcu_reclaim kernel/rcu/rcu.h:118 [inline] [] rcu_do_batch kernel/rcu/tree.c:2789 [inline] [] invoke_rcu_callbacks kernel/rcu/tree.c:3053 [inline] [] __rcu_process_callbacks kernel/rcu/tree.c:3020 [inline] [] rcu_process_callbacks+0x898/0x1300 kernel/rcu/tree.c:3037 [] __do_softirq+0x206/0x951 kernel/softirq.c:284 [] run_ksoftirqd+0x2e/0x60 kernel/softirq.c:676 [] smpboot_thread_fn+0x5c1/0x8f0 kernel/smpboot.c:163 [] kthread+0x26d/0x300 kernel/kthread.c:211 [] ret_from_fork+0x59/0x70 arch/x86/entry/entry_64.S:466 Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled Rebooting in 86400 seconds..