------------[ cut here ]------------ WARNING: CPU: 1 PID: 0 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: 0 Comm: swapper/1 Not tainted 4.9.79-g71f1469 #25 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ffff8801db307cb8 ffffffff81d94829 ffffffff83a47c40 ffff8801db307d90 ffffffff83f2f100 ffffffff832ec2d6 0000000000000009 ffff8801db307d80 ffffffff8142f531 0000000041b58ab3 ffffffff8418ab10 ffffffff8142f375 Call Trace: [ 24.776054] [] __dump_stack lib/dump_stack.c:15 [inline] [ 24.776054] [] 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 [] invoke_softirq kernel/softirq.c:364 [inline] [] irq_exit+0x165/0x190 kernel/softirq.c:405 [] exiting_irq arch/x86/include/asm/apic.h:659 [inline] [] smp_apic_timer_interrupt+0x7b/0xa0 arch/x86/kernel/apic/apic.c:960 [] apic_timer_interrupt+0xa0/0xb0 arch/x86/entry/entry_64.S:752 [ 24.917679] [] ? native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:53 [] arch_safe_halt arch/x86/include/asm/paravirt.h:103 [inline] [] default_idle+0x55/0x360 arch/x86/kernel/process.c:295 [] arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:286 [] default_idle_call+0x36/0x60 kernel/sched/idle.c:97 [] cpuidle_idle_call kernel/sched/idle.c:155 [inline] [] cpu_idle_loop kernel/sched/idle.c:248 [inline] [] cpu_startup_entry+0x2b0/0x380 kernel/sched/idle.c:303 [] start_secondary+0x303/0x3e0 arch/x86/kernel/smpboot.c:254 Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled Rebooting in 86400 seconds..