======================================
| [   50.149399][   T67] ------------[ cut here ]------------
| [   50.149862][   T67] RTNL: assertion failed at net/core/link_watch.c (59)
| [ 50.150133][ T67] WARNING: CPU: 2 PID: 67 at net/core/link_watch.c:59 default_operstate (net/core/link_watch.c:59 (discriminator 3))
| [   50.150481][   T67] Modules linked in: xfrm_user l2tp_ip6 l2tp_eth l2tp_ip l2tp_netlink l2tp_core cls_bpf sch_ingress
[   50.151179][   T67] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   50.151418][   T67] Workqueue: netns cleanup_net
[ 50.151624][ T67] RIP: 0010:default_operstate (net/core/link_watch.c:59 (discriminator 3))
[ 50.151817][ T67] Code: 83 e4 01 0f 85 03 ff ff ff c6 05 08 23 5c 02 01 90 ba 3b 00 00 00 48 c7 c6 00 7c 57 89 48 c7 c7 40 7c 57 89 e8 b3 b2 e5 fd 90 <0f> 0b 90 90 e9 d9 fe ff ff 48 89 ef e8 81 63 6d fe e9 f7 fd ff ff
All code
========
   0:	83 e4 01             	and    $0x1,%esp
   3:	0f 85 03 ff ff ff    	jne    0xffffffffffffff0c
   9:	c6 05 08 23 5c 02 01 	movb   $0x1,0x25c2308(%rip)        # 0x25c2318
  10:	90                   	nop
  11:	ba 3b 00 00 00       	mov    $0x3b,%edx
  16:	48 c7 c6 00 7c 57 89 	mov    $0xffffffff89577c00,%rsi
  1d:	48 c7 c7 40 7c 57 89 	mov    $0xffffffff89577c40,%rdi
  24:	e8 b3 b2 e5 fd       	call   0xfffffffffde5b2dc
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	e9 d9 fe ff ff       	jmp    0xffffffffffffff0c
  33:	48 89 ef             	mov    %rbp,%rdi
  36:	e8 81 63 6d fe       	call   0xfffffffffe6d63bc
  3b:	e9 f7 fd ff ff       	jmp    0xfffffffffffffe37

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	e9 d9 fe ff ff       	jmp    0xfffffffffffffee2
   9:	48 89 ef             	mov    %rbp,%rdi
   c:	e8 81 63 6d fe       	call   0xfffffffffe6d6392
  11:	e9 f7 fd ff ff       	jmp    0xfffffffffffffe0d
[   50.152456][   T67] RSP: 0018:ffffc90000487a48 EFLAGS: 00010282
[   50.152703][   T67] RAX: 0000000000000000 RBX: ffff88800a714000 RCX: 1ffffffff13bdd8c
[   50.152979][   T67] RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000001
[   50.153298][   T67] RBP: 0000000000000000 R08: 0000000000000000 R09: fffffbfff13bdd8c
[   50.153567][   T67] R10: 0000000000000003 R11: ffff888009188040 R12: 0000000000000000
[   50.153825][   T67] R13: dffffc0000000000 R14: ffff88800a711000 R15: ffff88800a7145c0
[   50.154123][   T67] FS:  0000000000000000(0000) GS:ffff88806d100000(0000) knlGS:0000000000000000
[   50.154524][   T67] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   50.154839][   T67] CR2: 00007f6d06f9b050 CR3: 000000005313a004 CR4: 0000000000772ef0
[   50.155194][   T67] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   50.155539][   T67] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   50.155867][   T67] PKRU: 55555554
[   50.156077][   T67] Call Trace:
[   50.156294][   T67]  <TASK>
[ 50.156462][ T67] ? default_operstate (net/core/link_watch.c:59 (discriminator 3))
[ 50.156719][ T67] ? __warn (kernel/panic.c:748)
[ 50.156923][ T67] ? default_operstate (net/core/link_watch.c:59 (discriminator 3))
[ 50.157125][ T67] ? report_bug (lib/bug.c:201 lib/bug.c:219)
[ 50.157337][ T67] ? handle_bug (arch/x86/kernel/traps.c:285)
[ 50.157483][ T67] ? exc_invalid_op (arch/x86/kernel/traps.c:309 (discriminator 1))
[ 50.157658][ T67] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:621)
[ 50.157852][ T67] ? default_operstate (net/core/link_watch.c:59 (discriminator 3))
[ 50.158038][ T67] ? default_operstate (net/core/link_watch.c:59 (discriminator 3))
[ 50.158226][ T67] rfc2863_policy (net/core/link_watch.c:78)
[ 50.158422][ T67] linkwatch_do_dev (net/core/link_watch.c:180)
[ 50.158599][ T67] netdev_run_todo (net/core/dev.c:10894 (discriminator 2))
[ 50.158783][ T67] ? __pfx_netdev_run_todo (net/core/dev.c:10867)
[ 50.158969][ T67] ? __pfx_unregister_netdevice_queue (net/core/dev.c:11455)
[ 50.159203][ T67] default_device_exit_batch (net/core/dev.c:12051)
[ 50.159401][ T67] ? __pfx_default_device_exit_batch (net/core/dev.c:12051)
[ 50.159632][ T67] ? ops_exit_list (net/core/net_namespace.c:171 (discriminator 3))
[ 50.159840][ T67] cleanup_net (net/core/net_namespace.c:647 (discriminator 3))
[ 50.160024][ T67] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 50.160212][ T67] ? __pfx_cleanup_net (net/core/net_namespace.c:592)
[ 50.160423][ T67] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 37))
[ 50.160610][ T67] ? lock_acquire (kernel/locking/lockdep.c:5822)
[ 50.160801][ T67] ? process_one_work (kernel/workqueue.c:3205)
[ 50.161000][ T67] process_one_work (kernel/workqueue.c:3229)
[ 50.161526][ T67] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 50.161711][ T67] ? __pfx_process_one_work (kernel/workqueue.c:3131)
[ 50.161905][ T67] ? assign_work (kernel/workqueue.c:1200)
[ 50.162094][ T67] worker_thread (kernel/workqueue.c:3304 kernel/workqueue.c:3391)
[ 50.162288][ T67] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406)
[ 50.162522][ T67] ? __pfx_worker_thread (kernel/workqueue.c:3337)
[ 50.162830][ T67] ? __pfx_worker_thread (kernel/workqueue.c:3337)
[ 50.163010][ T67] kthread (kernel/kthread.c:389)
[ 50.163224][ T67] ? __pfx_kthread (kernel/kthread.c:342)
[ 50.163425][ T67] ret_from_fork (arch/x86/kernel/process.c:147)
[ 50.163603][ T67] ? __pfx_kthread (kernel/kthread.c:342)


Finger prints:
default_operstate:rfc2863_policy:linkwatch_do_dev:netdev_run_todo:default_device_exit_batch