======================================
| [ 1360.122771][   T68] br0: port 1(veth1) entered disabled state
| [ 1360.171410][   T68] ------------[ cut here ]------------
| [ 1360.171609][ T68] WARNING: CPU: 0 PID: 68 at net/core/rtnetlink.c:135 __rtnl_unlock (net/core/rtnetlink.c:135 (discriminator 1))
| [ 1360.171880][   T68] Modules linked in: nft_meta_bridge br_netfilter macvlan sctp_diag nft_limit nfnetlink_queue nft_queue sctp ip6_udp_tunnel udp_tunnel nft_numgen esp4 sha1_generic xfrm_user 8021q bridge stp llc nft_flow_offload nf_flow_table_inet nf_flow_table nf_conntrack_netlink nft_redir nft_nat nft_masq nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 tcp_diag inet_diag veth nf_tables libcrc32c
[ 1360.173278][   T68] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[ 1360.173468][   T68] Workqueue: netns cleanup_net
[ 1360.173636][ T68] RIP: 0010:__rtnl_unlock (net/core/rtnetlink.c:135 (discriminator 1))
[ 1360.173796][ T68] Code: ff 31 d2 be 8f 00 00 00 48 c7 c7 60 34 97 a6 e8 3a 3f f3 fd e8 05 ad 72 00 48 85 db 75 c4 48 83 c4 08 5b 5d c3 cc cc cc cc 90 <0f> 0b 90 eb 8e 48 89 f7 48 89 34 24 e8 53 dd 71 fe 48 8b 34 24 eb
All code
========
   0:	ff 31                	push   (%rcx)
   2:	d2 be 8f 00 00 00    	sarb   %cl,0x8f(%rsi)
   8:	48 c7 c7 60 34 97 a6 	mov    $0xffffffffa6973460,%rdi
   f:	e8 3a 3f f3 fd       	call   0xfffffffffdf33f4e
  14:	e8 05 ad 72 00       	call   0x72ad1e
  19:	48 85 db             	test   %rbx,%rbx
  1c:	75 c4                	jne    0xffffffffffffffe2
  1e:	48 83 c4 08          	add    $0x8,%rsp
  22:	5b                   	pop    %rbx
  23:	5d                   	pop    %rbp
  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 8e                	jmp    0xffffffffffffffbd
  2f:	48 89 f7             	mov    %rsi,%rdi
  32:	48 89 34 24          	mov    %rsi,(%rsp)
  36:	e8 53 dd 71 fe       	call   0xfffffffffe71dd8e
  3b:	48 8b 34 24          	mov    (%rsp),%rsi
  3f:	eb                   	.byte 0xeb

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	eb 8e                	jmp    0xffffffffffffff93
   5:	48 89 f7             	mov    %rsi,%rdi
   8:	48 89 34 24          	mov    %rsi,(%rsp)
   c:	e8 53 dd 71 fe       	call   0xfffffffffe71dd64
  11:	48 8b 34 24          	mov    (%rsp),%rsi
  15:	eb                   	.byte 0xeb
[ 1360.174328][   T68] RSP: 0018:ffffc90000497a60 EFLAGS: 00010287
[ 1360.174520][   T68] RAX: ffff88801a7c45b0 RBX: ffff8880085a2300 RCX: ffffffffa61048aa
[ 1360.174763][   T68] RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffff888014a32178
[ 1360.174993][   T68] RBP: ffff888014a321b8 R08: 0000000000000001 R09: fffff52000092f26
[ 1360.175214][   T68] R10: ffffc90000497937 R11: ffff8880085a2300 R12: ffffc90000497be0
[ 1360.175453][   T68] R13: 0000000000000000 R14: dffffc0000000000 R15: ffffc90000497b10
[ 1360.175686][   T68] FS:  0000000000000000(0000) GS:ffff888036000000(0000) knlGS:0000000000000000
[ 1360.175948][   T68] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1360.176140][   T68] CR2: 00007ffcface9a28 CR3: 0000000011e2c002 CR4: 0000000000772ef0
[ 1360.176374][   T68] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1360.176605][   T68] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 1360.176833][   T68] PKRU: 55555554
[ 1360.176950][   T68] Call Trace:
[ 1360.177069][   T68]  <TASK>
[ 1360.177153][ T68] ? __rtnl_unlock (net/core/rtnetlink.c:135 (discriminator 1))
[ 1360.177319][ T68] ? __warn (kernel/panic.c:748)
[ 1360.177436][ T68] ? __rtnl_unlock (net/core/rtnetlink.c:135 (discriminator 1))
[ 1360.177592][ T68] ? report_bug (lib/bug.c:201 lib/bug.c:219)
[ 1360.177747][ T68] ? handle_bug (arch/x86/kernel/traps.c:285)
[ 1360.177863][ T68] ? exc_invalid_op (arch/x86/kernel/traps.c:309 (discriminator 1))
[ 1360.178013][ T68] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:621)
[ 1360.178174][ T68] ? __mutex_unlock_slowpath (./arch/x86/include/asm/atomic64_64.h:101 ./include/linux/atomic/atomic-arch-fallback.h:4329 ./include/linux/atomic/atomic-long.h:1506 ./include/linux/atomic/atomic-instrumented.h:4481 kernel/locking/mutex.c:913)
[ 1360.178339][ T68] ? __rtnl_unlock (net/core/rtnetlink.c:135 (discriminator 1))
[ 1360.178492][ T68] unregister_netdevice_many_notify (net/core/dev.c:11453 net/core/dev.c:11638)
[ 1360.178689][ T68] ? mark_held_locks (kernel/locking/lockdep.c:4321)
[ 1360.178843][ T68] ? __pfx_unregister_netdevice_many_notify (net/core/dev.c:11536)
[ 1360.179030][ T68] ? mutex_is_locked (./arch/x86/include/asm/atomic64_64.h:15 ./include/linux/atomic/atomic-arch-fallback.h:2583 ./include/linux/atomic/atomic-long.h:38 ./include/linux/atomic/atomic-instrumented.h:3189 kernel/locking/mutex.h:47 kernel/locking/mutex.c:66)
[ 1360.179177][ T68] ? rtnl_is_locked (net/core/rtnetlink.c:163)
[ 1360.179352][ T68] ? mutex_is_locked (./arch/x86/include/asm/atomic64_64.h:15 ./include/linux/atomic/atomic-arch-fallback.h:2583 ./include/linux/atomic/atomic-long.h:38 ./include/linux/atomic/atomic-instrumented.h:3189 kernel/locking/mutex.h:47 kernel/locking/mutex.c:66)
[ 1360.179504][ T68] ? nexthop_net_exit_batch_rtnl (net/ipv4/nexthop.c:585 net/ipv4/nexthop.c:2158 net/ipv4/nexthop.c:2666 net/ipv4/nexthop.c:4010)
[ 1360.179699][ T68] cleanup_net (net/core/net_namespace.c:648)
[ 1360.179849][ T68] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 1360.180001][ T68] ? __pfx_cleanup_net (net/core/net_namespace.c:594)
[ 1360.180148][ T68] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 37))
[ 1360.180312][ T68] ? lock_acquire (kernel/locking/lockdep.c:5822)
[ 1360.180471][ T68] ? process_one_work (kernel/workqueue.c:3205)
[ 1360.180635][ T68] process_one_work (kernel/workqueue.c:3229)
[ 1360.180800][ T68] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 1360.180951][ T68] ? __pfx_process_one_work (kernel/workqueue.c:3131)
[ 1360.181110][ T68] ? assign_work (kernel/workqueue.c:1200)
[ 1360.181278][ T68] worker_thread (kernel/workqueue.c:3304 kernel/workqueue.c:3391)
[ 1360.181443][ T68] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406)
[ 1360.181649][ T68] ? __pfx_worker_thread (kernel/workqueue.c:3337)
[ 1360.181802][ T68] ? __pfx_worker_thread (kernel/workqueue.c:3337)
[ 1360.181953][ T68] kthread (kernel/kthread.c:389)
[ 1360.182066][ T68] ? __pfx_kthread (kernel/kthread.c:342)
[ 1360.182219][ T68] ret_from_fork (arch/x86/kernel/process.c:147)
[ 1360.182381][ T68] ? __pfx_kthread (kernel/kthread.c:342)


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