======================================
| [  201.311691] br0: port 1(veth1) entered disabled state
| [  201.322198] ------------[ cut here ]------------
| [  201.322259] WARNING: CPU: 0 PID: 11 at net/core/rtnetlink.c:135 __rtnl_unlock (net/core/rtnetlink.c:135 (discriminator 1))
| [  201.322347] Modules linked in: nft_meta_bridge macvlan nf_conntrack_ftp ts_kmp ts_bm xt_string ebtable_filter ebt_redirect ebt_ip ebtable_broute ebtables vxlan sctp ip6_udp_tunnel udp_tunnel sch_netem cls_u32 sch_htb nft_synproxy nf_synproxy_core nf_log_syslog nft_log nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib ip6t_rpfilter ipt_rpfilter dummy xt_REDIRECT xt_nat ip_vs_rr ip_vs ipip nft_quota esp4 sha1_generic xfrm_user 8021q nft_flow_offload nf_flow_table_inet nf_flow_table nfnetlink_queue nft_queue br_netfilter bridge stp llc xt_conntrack nft_compat tun nft_ct nf_conntrack_netlink nft_redir nft_masq tcp_diag nft_nat nft_chain_nat nf_nat nf_conntrack inet_diag nft_tproxy nf_tproxy_ipv6 nf_tproxy_ipv4 nf_defrag_ipv6 nf_defrag_ipv4 nf_tables libcrc32c veth
[  201.322969] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  201.323018] Workqueue: netns cleanup_net
[  201.323065] RIP: 0010:__rtnl_unlock (net/core/rtnetlink.c:135 (discriminator 1))
[ 201.323110] Code: 1f 00 48 85 db 74 1c 48 89 de 31 ff 48 8b 1b ba 02 00 00 00 e8 32 27 fc ff e8 ad 68 1f 00 48 85 db 75 e4 5b c3 cc cc cc cc 90 <0f> 0b 90 eb c7 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90
All code
========
   0:	1f                   	(bad)
   1:	00 48 85             	add    %cl,-0x7b(%rax)
   4:	db 74 1c 48          	(bad)  0x48(%rsp,%rbx,1)
   8:	89 de                	mov    %ebx,%esi
   a:	31 ff                	xor    %edi,%edi
   c:	48 8b 1b             	mov    (%rbx),%rbx
   f:	ba 02 00 00 00       	mov    $0x2,%edx
  14:	e8 32 27 fc ff       	call   0xfffffffffffc274b
  19:	e8 ad 68 1f 00       	call   0x1f68cb
  1e:	48 85 db             	test   %rbx,%rbx
  21:	75 e4                	jne    0x7
  23:	5b                   	pop    %rbx
  24:	c3                   	ret
  25:	cc                   	int3
  26:	cc                   	int3
  27:	cc                   	int3
  28:	cc                   	int3
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	eb c7                	jmp    0xfffffffffffffff6
  2f:	66 66 2e 0f 1f 84 00 	data16 cs nopw 0x0(%rax,%rax,1)
  36:	00 00 00 00 
  3a:	90                   	nop
  3b:	90                   	nop
  3c:	90                   	nop
  3d:	90                   	nop
  3e:	90                   	nop
  3f:	90                   	nop

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	eb c7                	jmp    0xffffffffffffffcc
   5:	66 66 2e 0f 1f 84 00 	data16 cs nopw 0x0(%rax,%rax,1)
   c:	00 00 00 00 
  10:	90                   	nop
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
[  201.323247] RSP: 0018:ffffb30a8005fd78 EFLAGS: 00010283
[  201.323288] RAX: ffff9cc687c024f8 RBX: 0000000000000000 RCX: ffff9cc687fcb548
[  201.323346] RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff9cc6851fc000
[  201.323414] RBP: ffffb30a8005fcc0 R08: ffff9cc68aa6c088 R09: ffff9cc68118da10
[  201.323473] R10: ffffb30a8005fca8 R11: ffffb30a8005fcb0 R12: dead000000000122
[  201.323532] R13: dead000000000100 R14: ffff9cc6877f4000 R15: 0000000000000000
[  201.323592] FS:  0000000000000000(0000) GS:ffff9cc6bec00000(0000) knlGS:0000000000000000
[  201.323652] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  201.323706] CR2: 00007f7aa7d9b000 CR3: 000000002ce42001 CR4: 0000000000772ef0
[  201.323774] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  201.323833] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  201.323891] PKRU: 55555554
[  201.323916] Call Trace:
[  201.323945]  <TASK>
[  201.323968] ? __warn (kernel/panic.c:748)
[  201.324006] ? __rtnl_unlock (net/core/rtnetlink.c:135 (discriminator 1))
[  201.324043] ? report_bug (lib/bug.c:201 lib/bug.c:219)
[  201.324079] ? handle_bug (arch/x86/kernel/traps.c:285)
[  201.324112] ? exc_invalid_op (arch/x86/kernel/traps.c:309 (discriminator 1))
[  201.324154] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:621)
[  201.324187] ? __rtnl_unlock (net/core/rtnetlink.c:135 (discriminator 1))
[  201.324219] unregister_netdevice_many_notify (./include/linux/kernel.h:73 net/core/dev.c:11470 net/core/dev.c:11639)
[  201.324265] cleanup_net (net/core/net_namespace.c:648)
[  201.324301] process_one_work (kernel/workqueue.c:3229)
[  201.324333] worker_thread (kernel/workqueue.c:3304 kernel/workqueue.c:3391)
[  201.324368] ? __pfx_worker_thread (kernel/workqueue.c:3337)
[  201.324415] kthread (kernel/kthread.c:389)
[  201.324448] ? __pfx_kthread (kernel/kthread.c:342)
[  201.324479] ret_from_fork (arch/x86/kernel/process.c:147)
[  201.324519] ? __pfx_kthread (kernel/kthread.c:342)


Finger prints:
__rtnl_unlock:unregister_netdevice_many_notify:cleanup_net:process_one_work:worker_thread