======================================
| [    7.349750] ------------[ cut here ]------------
| [    7.349869] refcount_t: underflow; use-after-free.
| [    7.349952] WARNING: CPU: 2 PID: 12 at lib/refcount.c:28 refcount_warn_saturate (lib/refcount.c:28 (discriminator 3))
| [    7.350053] Modules linked in:
[    7.350217] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[    7.350306] Workqueue: netns cleanup_net
[    7.350373] RIP: 0010:refcount_warn_saturate (lib/refcount.c:28 (discriminator 3))
[    7.350444] Code: b1 e8 88 98 ba ff 90 0f 0b 90 90 c3 80 3d 69 b4 eb 00 00 75 89 c6 05 60 b4 eb 00 01 90 48 c7 c7 98 6e d4 b1 e8 65 98 ba ff 90 <0f> 0b 90 90 c3 80 3d 44 b4 eb 00 00 0f 85 62 ff ff ff c6 05 37 b4
All code
========
   0:	b1 e8                	mov    $0xe8,%cl
   2:	88 98 ba ff 90 0f    	mov    %bl,0xf90ffba(%rax)
   8:	0b 90 90 c3 80 3d    	or     0x3d80c390(%rax),%edx
   e:	69 b4 eb 00 00 75 89 	imul   $0xb46005c6,-0x768b0000(%rbx,%rbp,8),%esi
  15:	c6 05 60 b4 
  19:	eb 00                	jmp    0x1b
  1b:	01 90 48 c7 c7 98    	add    %edx,-0x673838b8(%rax)
  21:	6e                   	outsb  %ds:(%rsi),(%dx)
  22:	d4                   	(bad)
  23:	b1 e8                	mov    $0xe8,%cl
  25:	65 98                	gs cwtl
  27:*	ba ff 90 0f 0b       	mov    $0xb0f90ff,%edx		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	c3                   	ret
  2f:	80 3d 44 b4 eb 00 00 	cmpb   $0x0,0xebb444(%rip)        # 0xebb47a
  36:	0f 85 62 ff ff ff    	jne    0xffffffffffffff9e
  3c:	c6                   	.byte 0xc6
  3d:	05                   	.byte 0x5
  3e:	37                   	(bad)
  3f:	b4                   	.byte 0xb4

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	c3                   	ret
   5:	80 3d 44 b4 eb 00 00 	cmpb   $0x0,0xebb444(%rip)        # 0xebb450
   c:	0f 85 62 ff ff ff    	jne    0xffffffffffffff74
  12:	c6                   	.byte 0xc6
  13:	05                   	.byte 0x5
  14:	37                   	(bad)
  15:	b4                   	.byte 0xb4
[    7.350636] RSP: 0018:ffffac2c00067d50 EFLAGS: 00010286
[    7.350715] RAX: 0000000000000000 RBX: ffffac2c00067d60 RCX: 00000000ffffdfff
[    7.350809] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001


Finger prints: