======================================
| [  420.893320] br0: port 1(veth1) entered disabled state
| [  420.904221] ------------[ cut here ]------------
| [  420.904291] WARNING: CPU: 0 PID: 66 at net/core/rtnetlink.c:135 __rtnl_unlock (net/core/rtnetlink.c:135 (discriminator 1))
| [  420.904384] Modules linked in: nft_meta_bridge br_netfilter macvlan bridge stp llc nft_masq nft_ct nf_conntrack_netlink nft_nat nft_numgen nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 sctp_diag nft_limit nfnetlink_queue nft_queue sctp ip6_udp_tunnel udp_tunnel tcp_diag inet_diag veth nf_tables libcrc32c
[  420.904662] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  420.904712] Workqueue: netns cleanup_net
[  420.904748] RIP: 0010:__rtnl_unlock (net/core/rtnetlink.c:135 (discriminator 1))
[ 420.904795] 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
[  420.904942] RSP: 0018:ffffb94980247d78 EFLAGS: 00010283
[  420.904991] RAX: ffff8fcb877874f8 RBX: 0000000000000000 RCX: ffff8fcb87784548
[  420.905069] RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff8fcb986cc000
[  420.905147] RBP: ffffb94980247cc0 R08: ffff8fcb878f1660 R09: ffff8fcb8118da10
[  420.905224] R10: ffffb94980247ca8 R11: ffffb94980247cb0 R12: dead000000000122
[  420.905287] R13: dead000000000100 R14: ffff8fcb81e22700 R15: 0000000000000000
[  420.905347] FS:  0000000000000000(0000) GS:ffff8fcbbec00000(0000) knlGS:0000000000000000
[  420.905405] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  420.905452] CR2: 000055b030de9dec CR3: 000000000efec004 CR4: 0000000000772ef0
[  420.905507] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  420.905562] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  420.905619] PKRU: 55555554
[  420.905643] Call Trace:
[  420.905667]  <TASK>
[  420.905691] ? __warn (kernel/panic.c:748)
[  420.905731] ? __rtnl_unlock (net/core/rtnetlink.c:135 (discriminator 1))
[  420.905776] ? report_bug (lib/bug.c:201 lib/bug.c:219)
[  420.905826] ? handle_bug (arch/x86/kernel/traps.c:285)
[  420.905858] ? exc_invalid_op (arch/x86/kernel/traps.c:309 (discriminator 1))
[  420.905889] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:621)
[  420.905921] ? __rtnl_unlock (net/core/rtnetlink.c:135 (discriminator 1))
[  420.905954] unregister_netdevice_many_notify (./include/linux/kernel.h:73 net/core/dev.c:11470 net/core/dev.c:11639)
[  420.906000] cleanup_net (net/core/net_namespace.c:648)
[  420.906035] process_one_work (kernel/workqueue.c:3229)
[  420.906082] worker_thread (kernel/workqueue.c:3304 kernel/workqueue.c:3391)
[  420.906115] ? __pfx_worker_thread (kernel/workqueue.c:3337)
[  420.906157] kthread (kernel/kthread.c:389)
[  420.906192] ? __pfx_kthread (kernel/kthread.c:342)
[  420.906224] ret_from_fork (arch/x86/kernel/process.c:147)
[  420.906261] ? __pfx_kthread (kernel/kthread.c:342)


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