======================================
| [   56.992786][   T67] ------------[ cut here ]------------
| [   56.993375][   T67] RTNL: assertion failed at net/core/link_watch.c (59)
| [ 56.993810][ T67] WARNING: CPU: 2 PID: 67 at net/core/link_watch.c:59 default_operstate (net/core/link_watch.c:59 (discriminator 3))
| [   56.994322][   T67] Modules linked in: act_gact cls_flower sch_ingress macvlan 8021q vxlan ip6_udp_tunnel udp_tunnel bridge stp llc vrf veth
[   56.995600][   T67] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   56.995931][   T67] Workqueue: netns cleanup_net
[ 56.996222][ T67] RIP: 0010:default_operstate (net/core/link_watch.c:59 (discriminator 3))
[ 56.996525][ T67] Code: 83 e4 01 0f 85 03 ff ff ff c6 05 2e 39 3a 02 01 90 ba 3b 00 00 00 48 c7 c6 00 2b 77 9d 48 c7 c7 40 2b 77 9d e8 13 95 ea fd 90 <0f> 0b 90 90 e9 d9 fe ff ff 48 89 ef e8 d1 bb 71 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 2e 39 3a 02 01 	movb   $0x1,0x23a392e(%rip)        # 0x23a393e
  10:	90                   	nop
  11:	ba 3b 00 00 00       	mov    $0x3b,%edx
  16:	48 c7 c6 00 2b 77 9d 	mov    $0xffffffff9d772b00,%rsi
  1d:	48 c7 c7 40 2b 77 9d 	mov    $0xffffffff9d772b40,%rdi
  24:	e8 13 95 ea fd       	call   0xfffffffffdea953c
  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 d1 bb 71 fe       	call   0xfffffffffe71bc0c
  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 d1 bb 71 fe       	call   0xfffffffffe71bbe2
  11:	e9 f7 fd ff ff       	jmp    0xfffffffffffffe0d
[   56.997318][   T67] RSP: 0018:ffffc90000487ae8 EFLAGS: 00010286
[   56.997551][   T67] RAX: 0000000000000000 RBX: ffff888008c69000 RCX: 1ffffffff3bfb58c
[   56.997832][   T67] RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000001
[   56.998080][   T67] RBP: 000000000000000d R08: 0000000000000000 R09: fffffbfff3bfb58c
[   56.998420][   T67] R10: 0000000000000003 R11: ffff888008bb8040 R12: 0000000000000000
[   56.998704][   T67] R13: dffffc0000000000 R14: ffff88800254c000 R15: ffff888008c695b0
[   56.998941][   T67] FS:  0000000000000000(0000) GS:ffff888036100000(0000) knlGS:0000000000000000
[   56.999241][   T67] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   56.999468][   T67] CR2: 00007efee4ea2270 CR3: 000000000d526003 CR4: 0000000000772ef0
[   56.999714][   T67] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   56.999963][   T67] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   57.000528][   T67] PKRU: 55555554
[   57.000664][   T67] Call Trace:
[   57.000802][   T67]  <TASK>
[ 57.000903][ T67] ? default_operstate (net/core/link_watch.c:59 (discriminator 3))
[ 57.001100][ T67] ? __warn (kernel/panic.c:748)
[ 57.001262][ T67] ? do_raw_spin_unlock (./arch/x86/include/asm/atomic.h:23 ./include/linux/atomic/atomic-arch-fallback.h:457 ./include/linux/atomic/atomic-instrumented.h:33 ./include/asm-generic/qspinlock.h:57 kernel/locking/spinlock_debug.c:101 kernel/locking/spinlock_debug.c:141)
[ 57.001466][ T67] ? default_operstate (net/core/link_watch.c:59 (discriminator 3))
[ 57.001640][ T67] ? report_bug (lib/bug.c:201 lib/bug.c:219)
[ 57.001817][ T67] ? handle_bug (arch/x86/kernel/traps.c:285)
[ 57.001950][ T67] ? exc_invalid_op (arch/x86/kernel/traps.c:309 (discriminator 1))
[ 57.002137][ T67] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:621)
[ 57.002347][ T67] ? default_operstate (net/core/link_watch.c:59 (discriminator 3))
[ 57.002530][ T67] ? default_operstate (net/core/link_watch.c:59 (discriminator 3))
[ 57.002701][ T67] rfc2863_policy (net/core/link_watch.c:78)
[ 57.002887][ T67] linkwatch_do_dev (net/core/link_watch.c:180)
[ 57.003061][ T67] netdev_run_todo (net/core/dev.c:10894 (discriminator 2))
[ 57.003249][ T67] ? __pfx_netdev_run_todo (net/core/dev.c:10867)
[ 57.003421][ T67] ? 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)
[ 57.003619][ T67] ? 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)
[ 57.003828][ T67] cleanup_net (net/core/net_namespace.c:647)
[ 57.003994][ T67] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 57.004184][ T67] ? __pfx_cleanup_net (net/core/net_namespace.c:592)
[ 57.004355][ T67] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 37))
[ 57.004536][ T67] ? lock_acquire (kernel/locking/lockdep.c:5822)
[ 57.004703][ T67] ? process_one_work (kernel/workqueue.c:3205)
[ 57.004887][ T67] process_one_work (kernel/workqueue.c:3229)
[ 57.005060][ T67] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 57.005241][ T67] ? __pfx_process_one_work (kernel/workqueue.c:3131)
[ 57.005417][ T67] ? assign_work (kernel/workqueue.c:1200)
[ 57.005612][ T67] worker_thread (kernel/workqueue.c:3304 kernel/workqueue.c:3391)
[ 57.005782][ T67] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406)
[ 57.005990][ T67] ? __pfx_worker_thread (kernel/workqueue.c:3337)
[ 57.006211][ T67] ? __pfx_worker_thread (kernel/workqueue.c:3337)
[ 57.006384][ T67] kthread (kernel/kthread.c:389)
[ 57.006540][ T67] ? __pfx_kthread (kernel/kthread.c:342)
[ 57.006735][ T67] ret_from_fork (arch/x86/kernel/process.c:147)
[ 57.006905][ T67] ? __pfx_kthread (kernel/kthread.c:342)


Finger prints:
default_operstate:rfc2863_policy:linkwatch_do_dev:netdev_run_todo:cleanup_net