======================================
| [   10.988257] ------------[ cut here ]------------
| [   10.988311] RTNL: assertion failed at net/core/link_watch.c (59)
| [   10.988378] WARNING: CPU: 1 PID: 65 at net/core/link_watch.c:59 rfc2863_policy (net/core/link_watch.c:59 net/core/link_watch.c:76)
| [   10.988440] Modules linked in: openvswitch psample nf_nat nf_conntrack libcrc32c nf_defrag_ipv6 nf_defrag_ipv4 nsh vxlan dccp_ipv6 dccp_ipv4 dccp [last unloaded: test_blackhole_dev]
[   10.988613] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   10.988656] Workqueue: netns cleanup_net
[   10.988686] RIP: 0010:rfc2863_policy (net/core/link_watch.c:59 net/core/link_watch.c:76)
[ 10.988727] Code: 80 3d 27 7d 07 01 00 75 ca c6 05 1e 7d 07 01 01 90 ba 3b 00 00 00 48 c7 c6 8d f8 db a6 48 c7 c7 b0 cc cd a6 e8 7f 37 56 ff 90 <0f> 0b 90 90 eb a3 83 f8 06 0f 85 14 ff ff ff b8 05 00 00 00 e9 0a
All code
========
   0:	80 3d 27 7d 07 01 00 	cmpb   $0x0,0x1077d27(%rip)        # 0x1077d2e
   7:	75 ca                	jne    0xffffffffffffffd3
   9:	c6 05 1e 7d 07 01 01 	movb   $0x1,0x1077d1e(%rip)        # 0x1077d2e
  10:	90                   	nop
  11:	ba 3b 00 00 00       	mov    $0x3b,%edx
  16:	48 c7 c6 8d f8 db a6 	mov    $0xffffffffa6dbf88d,%rsi
  1d:	48 c7 c7 b0 cc cd a6 	mov    $0xffffffffa6cdccb0,%rdi
  24:	e8 7f 37 56 ff       	call   0xffffffffff5637a8
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	eb a3                	jmp    0xffffffffffffffd3
  30:	83 f8 06             	cmp    $0x6,%eax
  33:	0f 85 14 ff ff ff    	jne    0xffffffffffffff4d
  39:	b8 05 00 00 00       	mov    $0x5,%eax
  3e:	e9                   	.byte 0xe9
  3f:	0a                   	.byte 0xa

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	eb a3                	jmp    0xffffffffffffffa9
   6:	83 f8 06             	cmp    $0x6,%eax
   9:	0f 85 14 ff ff ff    	jne    0xffffffffffffff23
   f:	b8 05 00 00 00       	mov    $0x5,%eax
  14:	e9                   	.byte 0xe9
  15:	0a                   	.byte 0xa
[   10.988847] RSP: 0018:ffffa14f40247d10 EFLAGS: 00010286
[   10.988886] RAX: 0000000000000000 RBX: ffff8bdec7549000 RCX: 00000000ffffdfff
[   10.988937] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   10.988989] RBP: 0000000000000000 R08: ffffffffa715a968 R09: 00000000ffffdfff
[   10.989040] R10: ffffffffa707a980 R11: ffffffffa712a980 R12: dead000000000122
[   10.989091] R13: dead000000000100 R14: ffffffffa6dbf1fe R15: ffff8bdec754a000
[   10.989151] FS:  0000000000000000(0000) GS:ffff8bdefec80000(0000) knlGS:0000000000000000
[   10.989210] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   10.989251] CR2: 000055f57375fdec CR3: 00000000049b6003 CR4: 0000000000772ef0
[   10.989304] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   10.989359] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   10.989410] PKRU: 55555554
[   10.989428] Call Trace:
[   10.989447]  <TASK>
[   10.989469] ? __warn (kernel/panic.c:748)
[   10.989497] ? rfc2863_policy (net/core/link_watch.c:59 net/core/link_watch.c:76)
[   10.989528] ? report_bug (lib/bug.c:201 lib/bug.c:219)
[   10.989560] ? prb_read_valid (kernel/printk/printk_ringbuffer.c:2183)
[   10.989591] ? handle_bug (arch/x86/kernel/traps.c:285)
[   10.989623] ? exc_invalid_op (arch/x86/kernel/traps.c:309 (discriminator 1))
[   10.989654] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:621)
[   10.989687] ? rfc2863_policy (net/core/link_watch.c:59 net/core/link_watch.c:76)
[   10.989717] linkwatch_do_dev (net/core/link_watch.c:180)
[   10.989743] netdev_run_todo (net/core/dev.c:10894 (discriminator 2))
[   10.989775] ? unregister_netdevice_queue (net/core/dev.c:11456)
[   10.989814] ? enable_work (kernel/workqueue.c:4310 kernel/workqueue.c:4484)
[   10.989845] default_device_exit_batch (net/core/dev.c:12077)
[   10.989880] cleanup_net (net/core/net_namespace.c:647 (discriminator 3))
[   10.989911] process_one_work (kernel/workqueue.c:3229)
[   10.989937] worker_thread (kernel/workqueue.c:3304 kernel/workqueue.c:3391)
[   10.989962] ? __pfx_worker_thread (kernel/workqueue.c:3337)
[   10.989995] kthread (kernel/kthread.c:389)
[   10.990026] ? __pfx_kthread (kernel/kthread.c:342)
[   10.990087] ret_from_fork (arch/x86/kernel/process.c:147)
[   10.990121] ? __pfx_kthread (kernel/kthread.c:342)


Finger prints:
rfc2863_policy:linkwatch_do_dev:netdev_run_todo:default_device_exit_batch:cleanup_net