======================================
| [   66.848069] ------------[ cut here ]------------
| [   66.848644] refcount_t: underflow; use-after-free.
| [   66.849288] WARNING: CPU: 1 PID: 11 at lib/refcount.c:28 refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) 
| [   66.850215] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel
[   66.851951] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   66.853329] Workqueue: netns cleanup_net
[   66.853701] RIP: 0010:refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) 
[ 66.854275] Code: 0b 90 90 c3 cc cc cc cc 80 3d 69 d4 67 01 00 0f 85 75 ff ff ff c6 05 5c d4 67 01 01 90 48 c7 c7 e8 37 73 a8 e8 a1 26 b4 ff 90 <0f> 0b 90 90 c3 cc cc cc cc 80 3d 3c d4 67 01 00 0f 85 4a ff ff ff
All code
========
   0:	0b 90 90 c3 cc cc    	or     -0x33333c70(%rax),%edx
   6:	cc                   	int3
   7:	cc                   	int3
   8:	80 3d 69 d4 67 01 00 	cmpb   $0x0,0x167d469(%rip)        # 0x167d478
   f:	0f 85 75 ff ff ff    	jne    0xffffffffffffff8a
  15:	c6 05 5c d4 67 01 01 	movb   $0x1,0x167d45c(%rip)        # 0x167d478
  1c:	90                   	nop
  1d:	48 c7 c7 e8 37 73 a8 	mov    $0xffffffffa87337e8,%rdi
  24:	e8 a1 26 b4 ff       	call   0xffffffffffb426ca
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	c3                   	ret
  2f:	cc                   	int3
  30:	cc                   	int3
  31:	cc                   	int3
  32:	cc                   	int3
  33:	80 3d 3c d4 67 01 00 	cmpb   $0x0,0x167d43c(%rip)        # 0x167d476
  3a:	0f 85 4a ff ff ff    	jne    0xffffffffffffff8a

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	c3                   	ret
   5:	cc                   	int3
   6:	cc                   	int3
   7:	cc                   	int3
   8:	cc                   	int3
   9:	80 3d 3c d4 67 01 00 	cmpb   $0x0,0x167d43c(%rip)        # 0x167d44c
  10:	0f 85 4a ff ff ff    	jne    0xffffffffffffff60
[   66.856290] RSP: 0018:ffffb03c80063d78 EFLAGS: 00010286
[   66.856763] RAX: 0000000000000000 RBX: ffff88a7c4fa4000 RCX: 00000000ffffdfff
[   66.857538] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   66.857995] RBP: ffff88a7c4fa4610 R08: ffffffffa8b78508 R09: 00000000ffffdfff
[   66.858425] R10: ffffffffa8a98520 R11: ffffffffa8b48520 R12: ffff88a7c4fa4000
[   66.858991] R13: ffffb03c80063e08 R14: ffff88a7c4fa4b80 R15: ffff88a7c223dc50
[   66.859514] FS:  0000000000000000(0000) GS:ffff88a7ffc80000(0000) knlGS:0000000000000000
[   66.860125] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   66.860423] CR2: 000055748232ddec CR3: 000000003da60005 CR4: 0000000000770ef0
[   66.860806] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   66.861319] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   66.861932] PKRU: 55555554
[   66.862091] Call Trace:
[   66.862229]  <TASK>
[   66.862473] ? __warn (kernel/panic.c:677) 
[   66.862748] ? refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) 
[   66.863259] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[   66.863704] ? handle_bug (arch/x86/kernel/traps.c:238) 
[   66.864144] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[   66.864559] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[   66.865042] ? refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) 
[   66.865570] ? refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) 
[   66.866121] br_sysfs_delbr (net/bridge/br_sysfs_br.c:1086) 
[   66.866546] br_dev_delete (net/bridge/br_if.c:396) 
[   66.867004] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[   66.867510] cleanup_net (net/core/net_namespace.c:630) 
[   66.867945] ? process_one_work (kernel/workqueue.c:2606) 
[   66.868466] process_one_work (kernel/workqueue.c:2633) 
[   66.868970] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[   66.869375] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[   66.869926] kthread (kernel/kthread.c:388) 
[   66.870244] ? __pfx_kthread (kernel/kthread.c:341) 
[   66.870686] ret_from_fork (arch/x86/kernel/process.c:147) 
[   66.871004] ? __pfx_kthread (kernel/kthread.c:341) 
[   66.871399] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   66.875611] ------------[ cut here ]------------
| [   66.875919] sysfs group 'bridge' not found for kobject 'br1'
| [   66.876513] WARNING: CPU: 1 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [   66.876956] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel
[   66.878209] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   66.879444] Workqueue: netns cleanup_net
[   66.880016] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 66.880286] Code: 48 89 ef 5d 41 5c e9 7a ad ff ff 48 89 ef e8 12 9b ff ff eb d1 90 49 8b 14 24 48 8b 33 48 c7 c7 d0 cd 72 a8 e8 ac 67 c5 ff 90 <0f> 0b 90 90 5b 5d 41 5c c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00
All code
========
   0:	48 89 ef             	mov    %rbp,%rdi
   3:	5d                   	pop    %rbp
   4:	41 5c                	pop    %r12
   6:	e9 7a ad ff ff       	jmp    0xffffffffffffad85
   b:	48 89 ef             	mov    %rbp,%rdi
   e:	e8 12 9b ff ff       	call   0xffffffffffff9b25
  13:	eb d1                	jmp    0xffffffffffffffe6
  15:	90                   	nop
  16:	49 8b 14 24          	mov    (%r12),%rdx
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 d0 cd 72 a8 	mov    $0xffffffffa872cdd0,%rdi
  24:	e8 ac 67 c5 ff       	call   0xffffffffffc567d5
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	5b                   	pop    %rbx
  2f:	5d                   	pop    %rbp
  30:	41 5c                	pop    %r12
  32:	c3                   	ret
  33:	cc                   	int3
  34:	cc                   	int3
  35:	cc                   	int3
  36:	cc                   	int3
  37:	66                   	data16
  38:	66                   	data16
  39:	2e                   	cs
  3a:	0f                   	.byte 0xf
  3b:	1f                   	(bad)
  3c:	84 00                	test   %al,(%rax)
	...

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	5b                   	pop    %rbx
   5:	5d                   	pop    %rbp
   6:	41 5c                	pop    %r12
   8:	c3                   	ret
   9:	cc                   	int3
   a:	cc                   	int3
   b:	cc                   	int3
   c:	cc                   	int3
   d:	66                   	data16
   e:	66                   	data16
   f:	2e                   	cs
  10:	0f                   	.byte 0xf
  11:	1f                   	(bad)
  12:	84 00                	test   %al,(%rax)
	...
[   66.882574] RSP: 0018:ffffb03c80063d70 EFLAGS: 00010286
[   66.883355] RAX: 0000000000000000 RBX: ffffffffa83472c0 RCX: 00000000ffffdfff
[   66.884351] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   66.885449] RBP: 0000000000000000 R08: ffffffffa8b78508 R09: 00000000ffffdfff
[   66.886578] R10: ffffffffa8a98520 R11: ffffffffa8b48520 R12: ffff88a7c4fa4610
[   66.887784] R13: ffffb03c80063e08 R14: ffff88a7c4fa4b80 R15: ffff88a7c223dc50
[   66.888271] FS:  0000000000000000(0000) GS:ffff88a7ffc80000(0000) knlGS:0000000000000000
[   66.888912] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   66.889281] CR2: 000055748232ddec CR3: 000000003da60005 CR4: 0000000000770ef0
[   66.890007] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   66.890654] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   66.891628] PKRU: 55555554
[   66.891926] Call Trace:
[   66.892228]  <TASK>
[   66.892472] ? __warn (kernel/panic.c:677) 
[   66.892883] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   66.893381] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[   66.893806] ? handle_bug (arch/x86/kernel/traps.c:238) 
[   66.894250] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[   66.894663] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[   66.895211] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   66.895692] br_dev_delete (net/bridge/br_if.c:396) 
[   66.896109] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[   66.896634] cleanup_net (net/core/net_namespace.c:630) 
[   66.897044] ? process_one_work (kernel/workqueue.c:2606) 
[   66.897548] process_one_work (kernel/workqueue.c:2633) 
[   66.898036] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[   66.898460] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[   66.898880] kthread (kernel/kthread.c:388) 
[   66.899289] ? __pfx_kthread (kernel/kthread.c:341) 
[   66.899688] ret_from_fork (arch/x86/kernel/process.c:147) 
[   66.900050] ? __pfx_kthread (kernel/kthread.c:341) 
[   66.900412] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   66.904694] ------------[ cut here ]------------
| [   66.905134] sysfs group 'bridge' not found for kobject 'br2'
| [   66.905570] WARNING: CPU: 1 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [   66.906041] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel
[   66.907289] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   66.908288] Workqueue: netns cleanup_net
[   66.908691] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 66.909185] Code: 48 89 ef 5d 41 5c e9 7a ad ff ff 48 89 ef e8 12 9b ff ff eb d1 90 49 8b 14 24 48 8b 33 48 c7 c7 d0 cd 72 a8 e8 ac 67 c5 ff 90 <0f> 0b 90 90 5b 5d 41 5c c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00
All code
========
   0:	48 89 ef             	mov    %rbp,%rdi
   3:	5d                   	pop    %rbp
   4:	41 5c                	pop    %r12
   6:	e9 7a ad ff ff       	jmp    0xffffffffffffad85
   b:	48 89 ef             	mov    %rbp,%rdi
   e:	e8 12 9b ff ff       	call   0xffffffffffff9b25
  13:	eb d1                	jmp    0xffffffffffffffe6
  15:	90                   	nop
  16:	49 8b 14 24          	mov    (%r12),%rdx
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 d0 cd 72 a8 	mov    $0xffffffffa872cdd0,%rdi
  24:	e8 ac 67 c5 ff       	call   0xffffffffffc567d5
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	5b                   	pop    %rbx
  2f:	5d                   	pop    %rbp
  30:	41 5c                	pop    %r12
  32:	c3                   	ret
  33:	cc                   	int3
  34:	cc                   	int3
  35:	cc                   	int3
  36:	cc                   	int3
  37:	66                   	data16
  38:	66                   	data16
  39:	2e                   	cs
  3a:	0f                   	.byte 0xf
  3b:	1f                   	(bad)
  3c:	84 00                	test   %al,(%rax)
	...

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	5b                   	pop    %rbx
   5:	5d                   	pop    %rbp
   6:	41 5c                	pop    %r12
   8:	c3                   	ret
   9:	cc                   	int3
   a:	cc                   	int3
   b:	cc                   	int3
   c:	cc                   	int3
   d:	66                   	data16
   e:	66                   	data16
   f:	2e                   	cs
  10:	0f                   	.byte 0xf
  11:	1f                   	(bad)
  12:	84 00                	test   %al,(%rax)
	...
[   66.911325] RSP: 0018:ffffb03c80063d70 EFLAGS: 00010286
[   66.911927] RAX: 0000000000000000 RBX: ffffffffa83472c0 RCX: 00000000ffffdfff
[   66.912753] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   66.913570] RBP: 0000000000000000 R08: ffffffffa8b78508 R09: 00000000ffffdfff
[   66.914287] R10: ffffffffa8a98520 R11: ffffffffa8b48520 R12: ffff88a7c4fa6610
[   66.914982] R13: ffffb03c80063e08 R14: ffff88a7c4fa6b80 R15: ffff88a7c223dc50
[   66.915665] FS:  0000000000000000(0000) GS:ffff88a7ffc80000(0000) knlGS:0000000000000000
[   66.916391] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   66.916928] CR2: 000055748232ddec CR3: 000000003da60005 CR4: 0000000000770ef0
[   66.917628] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   66.918310] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   66.918955] PKRU: 55555554
[   66.919245] Call Trace:
[   66.919490]  <TASK>
[   66.919624] ? __warn (kernel/panic.c:677) 
[   66.919835] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   66.920111] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[   66.920349] ? handle_bug (arch/x86/kernel/traps.c:238) 
[   66.920561] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[   66.920799] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[   66.921052] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   66.921294] br_dev_delete (net/bridge/br_if.c:396) 
[   66.921512] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[   66.921763] cleanup_net (net/core/net_namespace.c:630) 
[   66.921991] ? process_one_work (kernel/workqueue.c:2606) 
[   66.922236] process_one_work (kernel/workqueue.c:2633) 
[   66.922466] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[   66.922688] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[   66.922944] kthread (kernel/kthread.c:388) 
[   66.923141] ? __pfx_kthread (kernel/kthread.c:341) 
[   66.923360] ret_from_fork (arch/x86/kernel/process.c:147) 
[   66.923577] ? __pfx_kthread (kernel/kthread.c:341) 
[   66.923802] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   67.102993] ------------[ cut here ]------------
| [   67.103264] sysfs group 'bridge' not found for kobject 'br1'
| [   67.103588] WARNING: CPU: 1 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [   67.104036] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel
[   67.104820] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   67.105423] Workqueue: netns cleanup_net
[   67.105651] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 67.105929] Code: 48 89 ef 5d 41 5c e9 7a ad ff ff 48 89 ef e8 12 9b ff ff eb d1 90 49 8b 14 24 48 8b 33 48 c7 c7 d0 cd 72 a8 e8 ac 67 c5 ff 90 <0f> 0b 90 90 5b 5d 41 5c c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00
All code
========
   0:	48 89 ef             	mov    %rbp,%rdi
   3:	5d                   	pop    %rbp
   4:	41 5c                	pop    %r12
   6:	e9 7a ad ff ff       	jmp    0xffffffffffffad85
   b:	48 89 ef             	mov    %rbp,%rdi
   e:	e8 12 9b ff ff       	call   0xffffffffffff9b25
  13:	eb d1                	jmp    0xffffffffffffffe6
  15:	90                   	nop
  16:	49 8b 14 24          	mov    (%r12),%rdx
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 d0 cd 72 a8 	mov    $0xffffffffa872cdd0,%rdi
  24:	e8 ac 67 c5 ff       	call   0xffffffffffc567d5
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	5b                   	pop    %rbx
  2f:	5d                   	pop    %rbp
  30:	41 5c                	pop    %r12
  32:	c3                   	ret
  33:	cc                   	int3
  34:	cc                   	int3
  35:	cc                   	int3
  36:	cc                   	int3
  37:	66                   	data16
  38:	66                   	data16
  39:	2e                   	cs
  3a:	0f                   	.byte 0xf
  3b:	1f                   	(bad)
  3c:	84 00                	test   %al,(%rax)
	...

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	5b                   	pop    %rbx
   5:	5d                   	pop    %rbp
   6:	41 5c                	pop    %r12
   8:	c3                   	ret
   9:	cc                   	int3
   a:	cc                   	int3
   b:	cc                   	int3
   c:	cc                   	int3
   d:	66                   	data16
   e:	66                   	data16
   f:	2e                   	cs
  10:	0f                   	.byte 0xf
  11:	1f                   	(bad)
  12:	84 00                	test   %al,(%rax)
	...
[   67.106901] RSP: 0018:ffffb03c80063d70 EFLAGS: 00010286
[   67.107172] RAX: 0000000000000000 RBX: ffffffffa83472c0 RCX: 00000000ffffdfff
[   67.107533] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   67.107921] RBP: 0000000000000000 R08: ffffffffa8b78508 R09: 00000000ffffdfff
[   67.108300] R10: ffffffffa8a98520 R11: ffffffffa8b48520 R12: ffff88a7c5418610
[   67.108671] R13: ffffb03c80063e08 R14: ffff88a7c5418b80 R15: ffff88a7c2239750
[   67.109273] FS:  0000000000000000(0000) GS:ffff88a7ffc80000(0000) knlGS:0000000000000000
[   67.109684] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   67.109988] CR2: 000055748232ddec CR3: 000000003da60005 CR4: 0000000000770ef0
[   67.110375] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   67.110741] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   67.111111] PKRU: 55555554
[   67.111263] Call Trace:
[   67.111398]  <TASK>
[   67.111518] ? __warn (kernel/panic.c:677) 
[   67.111693] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   67.111934] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[   67.112133] ? handle_bug (arch/x86/kernel/traps.c:238) 
[   67.112330] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[   67.112533] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[   67.112767] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   67.112996] br_dev_delete (net/bridge/br_if.c:396) 
[   67.113194] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[   67.113429] cleanup_net (net/core/net_namespace.c:630) 
[   67.113625] ? process_one_work (kernel/workqueue.c:2606) 
[   67.113888] process_one_work (kernel/workqueue.c:2633) 
[   67.114173] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[   67.114380] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[   67.114635] kthread (kernel/kthread.c:388) 
[   67.114820] ? __pfx_kthread (kernel/kthread.c:341) 
[   67.115028] ret_from_fork (arch/x86/kernel/process.c:147) 
[   67.115221] ? __pfx_kthread (kernel/kthread.c:341) 
[   67.115419] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   67.118062] ------------[ cut here ]------------
| [   67.118316] sysfs group 'bridge' not found for kobject 'br2'
| [   67.118635] WARNING: CPU: 1 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [   67.119094] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel
[   67.119885] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   67.120486] Workqueue: netns cleanup_net
[   67.120701] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 67.120973] Code: 48 89 ef 5d 41 5c e9 7a ad ff ff 48 89 ef e8 12 9b ff ff eb d1 90 49 8b 14 24 48 8b 33 48 c7 c7 d0 cd 72 a8 e8 ac 67 c5 ff 90 <0f> 0b 90 90 5b 5d 41 5c c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00
All code
========
   0:	48 89 ef             	mov    %rbp,%rdi
   3:	5d                   	pop    %rbp
   4:	41 5c                	pop    %r12
   6:	e9 7a ad ff ff       	jmp    0xffffffffffffad85
   b:	48 89 ef             	mov    %rbp,%rdi
   e:	e8 12 9b ff ff       	call   0xffffffffffff9b25
  13:	eb d1                	jmp    0xffffffffffffffe6
  15:	90                   	nop
  16:	49 8b 14 24          	mov    (%r12),%rdx
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 d0 cd 72 a8 	mov    $0xffffffffa872cdd0,%rdi
  24:	e8 ac 67 c5 ff       	call   0xffffffffffc567d5
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	5b                   	pop    %rbx
  2f:	5d                   	pop    %rbp
  30:	41 5c                	pop    %r12
  32:	c3                   	ret
  33:	cc                   	int3
  34:	cc                   	int3
  35:	cc                   	int3
  36:	cc                   	int3
  37:	66                   	data16
  38:	66                   	data16
  39:	2e                   	cs
  3a:	0f                   	.byte 0xf
  3b:	1f                   	(bad)
  3c:	84 00                	test   %al,(%rax)
	...

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	5b                   	pop    %rbx
   5:	5d                   	pop    %rbp
   6:	41 5c                	pop    %r12
   8:	c3                   	ret
   9:	cc                   	int3
   a:	cc                   	int3
   b:	cc                   	int3
   c:	cc                   	int3
   d:	66                   	data16
   e:	66                   	data16
   f:	2e                   	cs
  10:	0f                   	.byte 0xf
  11:	1f                   	(bad)
  12:	84 00                	test   %al,(%rax)
	...
[   67.121939] RSP: 0018:ffffb03c80063d70 EFLAGS: 00010286
[   67.122232] RAX: 0000000000000000 RBX: ffffffffa83472c0 RCX: 00000000ffffdfff
[   67.122603] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   67.122996] RBP: 0000000000000000 R08: ffffffffa8b78508 R09: 00000000ffffdfff
[   67.123366] R10: ffffffffa8a98520 R11: ffffffffa8b48520 R12: ffff88a7c2716610
[   67.123735] R13: ffffb03c80063e08 R14: ffff88a7c2716b80 R15: ffff88a7c2239750
[   67.124120] FS:  0000000000000000(0000) GS:ffff88a7ffc80000(0000) knlGS:0000000000000000
[   67.124531] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   67.124841] CR2: 000055748232ddec CR3: 000000003da60005 CR4: 0000000000770ef0
[   67.125214] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   67.125575] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   67.125945] PKRU: 55555554
[   67.126090] Call Trace:
[   67.126225]  <TASK>
[   67.126342] ? __warn (kernel/panic.c:677) 
[   67.126519] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   67.126758] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[   67.126983] ? handle_bug (arch/x86/kernel/traps.c:238) 
[   67.127174] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[   67.127376] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[   67.127598] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   67.127834] br_dev_delete (net/bridge/br_if.c:396) 
[   67.128055] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[   67.128311] cleanup_net (net/core/net_namespace.c:630) 
[   67.128519] ? process_one_work (kernel/workqueue.c:2606) 
[   67.128753] process_one_work (kernel/workqueue.c:2633) 
[   67.129061] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[   67.129262] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[   67.129493] kthread (kernel/kthread.c:388) 
[   67.129673] ? __pfx_kthread (kernel/kthread.c:341) 
[   67.129879] ret_from_fork (arch/x86/kernel/process.c:147) 
[   67.130101] ? __pfx_kthread (kernel/kthread.c:341) 
[   67.130316] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   71.336983] ------------[ cut here ]------------
| [   71.337419] sysfs group 'bridge' not found for kobject 'br1'
| [   71.337957] WARNING: CPU: 3 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [   71.338748] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel
[   71.340302] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   71.341227] Workqueue: netns cleanup_net
[   71.341612] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 71.342065] Code: 48 89 ef 5d 41 5c e9 7a ad ff ff 48 89 ef e8 12 9b ff ff eb d1 90 49 8b 14 24 48 8b 33 48 c7 c7 d0 cd 72 a8 e8 ac 67 c5 ff 90 <0f> 0b 90 90 5b 5d 41 5c c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00
All code
========
   0:	48 89 ef             	mov    %rbp,%rdi
   3:	5d                   	pop    %rbp
   4:	41 5c                	pop    %r12
   6:	e9 7a ad ff ff       	jmp    0xffffffffffffad85
   b:	48 89 ef             	mov    %rbp,%rdi
   e:	e8 12 9b ff ff       	call   0xffffffffffff9b25
  13:	eb d1                	jmp    0xffffffffffffffe6
  15:	90                   	nop
  16:	49 8b 14 24          	mov    (%r12),%rdx
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 d0 cd 72 a8 	mov    $0xffffffffa872cdd0,%rdi
  24:	e8 ac 67 c5 ff       	call   0xffffffffffc567d5
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	5b                   	pop    %rbx
  2f:	5d                   	pop    %rbp
  30:	41 5c                	pop    %r12
  32:	c3                   	ret
  33:	cc                   	int3
  34:	cc                   	int3
  35:	cc                   	int3
  36:	cc                   	int3
  37:	66                   	data16
  38:	66                   	data16
  39:	2e                   	cs
  3a:	0f                   	.byte 0xf
  3b:	1f                   	(bad)
  3c:	84 00                	test   %al,(%rax)
	...

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	5b                   	pop    %rbx
   5:	5d                   	pop    %rbp
   6:	41 5c                	pop    %r12
   8:	c3                   	ret
   9:	cc                   	int3
   a:	cc                   	int3
   b:	cc                   	int3
   c:	cc                   	int3
   d:	66                   	data16
   e:	66                   	data16
   f:	2e                   	cs
  10:	0f                   	.byte 0xf
  11:	1f                   	(bad)
  12:	84 00                	test   %al,(%rax)
	...
[   71.343694] RSP: 0018:ffffb03c80063d70 EFLAGS: 00010286
[   71.344212] RAX: 0000000000000000 RBX: ffffffffa83472c0 RCX: 00000000ffffdfff
[   71.344584] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   71.345006] RBP: 0000000000000000 R08: ffffffffa8b78508 R09: 00000000ffffdfff
[   71.345369] R10: ffffffffa8a98520 R11: ffffffffa8b48520 R12: ffff88a7c4fa0610
[   71.345741] R13: ffffb03c80063e08 R14: ffff88a7c4fa0b80 R15: ffff88a7c126ae50
[   71.346125] FS:  0000000000000000(0000) GS:ffff88a7ffd80000(0000) knlGS:0000000000000000
[   71.346540] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   71.346851] CR2: 0000557483ba1e50 CR3: 000000003da60004 CR4: 0000000000770ef0
[   71.347218] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   71.347580] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   71.347955] PKRU: 55555554
[   71.348101] Call Trace:
[   71.348235]  <TASK>
[   71.348354] ? __warn (kernel/panic.c:677) 
[   71.348532] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   71.348752] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[   71.348977] ? handle_bug (arch/x86/kernel/traps.c:238) 
[   71.349167] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[   71.349371] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[   71.349595] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   71.349834] br_dev_delete (net/bridge/br_if.c:396) 
[   71.350040] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[   71.350272] cleanup_net (net/core/net_namespace.c:630) 
[   71.350466] ? process_one_work (kernel/workqueue.c:2606) 
[   71.350690] process_one_work (kernel/workqueue.c:2633) 
[   71.350918] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[   71.351141] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[   71.351383] kthread (kernel/kthread.c:388) 
[   71.351564] ? __pfx_kthread (kernel/kthread.c:341) 
[   71.351795] ret_from_fork (arch/x86/kernel/process.c:147) 
[   71.351996] ? __pfx_kthread (kernel/kthread.c:341) 
[   71.352197] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   71.354743] ------------[ cut here ]------------
| [   71.355038] kobject: '' (00000000df597171): is not initialized, yet kobject_put() is being called.
| [   71.355707] WARNING: CPU: 3 PID: 11 at lib/kobject.c:730 kobject_put (lib/kobject.c:730 (discriminator 1)) 
| [   71.356248] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel
[   71.357297] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   71.358203] Workqueue: netns cleanup_net
[   71.358558] RIP: 0010:kobject_put (lib/kobject.c:730 (discriminator 1)) 
[ 71.358943] Code: 89 ef e8 fe ad 4f ff 4d 85 e4 74 c0 4c 89 e5 f6 45 3c 01 75 a3 90 48 8b 75 00 48 89 ea 48 c7 c7 88 ce 7a a8 e8 dc 42 2a ff 90 <0f> 0b 90 90 eb 88 c3 cc cc cc cc 5b be 03 00 00 00 5d 41 5c 41 5d
All code
========
   0:	89 ef                	mov    %ebp,%edi
   2:	e8 fe ad 4f ff       	call   0xffffffffff4fae05
   7:	4d 85 e4             	test   %r12,%r12
   a:	74 c0                	je     0xffffffffffffffcc
   c:	4c 89 e5             	mov    %r12,%rbp
   f:	f6 45 3c 01          	testb  $0x1,0x3c(%rbp)
  13:	75 a3                	jne    0xffffffffffffffb8
  15:	90                   	nop
  16:	48 8b 75 00          	mov    0x0(%rbp),%rsi
  1a:	48 89 ea             	mov    %rbp,%rdx
  1d:	48 c7 c7 88 ce 7a a8 	mov    $0xffffffffa87ace88,%rdi
  24:	e8 dc 42 2a ff       	call   0xffffffffff2a4305
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	eb 88                	jmp    0xffffffffffffffb8
  30:	c3                   	ret
  31:	cc                   	int3
  32:	cc                   	int3
  33:	cc                   	int3
  34:	cc                   	int3
  35:	5b                   	pop    %rbx
  36:	be 03 00 00 00       	mov    $0x3,%esi
  3b:	5d                   	pop    %rbp
  3c:	41 5c                	pop    %r12
  3e:	41 5d                	pop    %r13

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	eb 88                	jmp    0xffffffffffffff8e
   6:	c3                   	ret
   7:	cc                   	int3
   8:	cc                   	int3
   9:	cc                   	int3
   a:	cc                   	int3
   b:	5b                   	pop    %rbx
   c:	be 03 00 00 00       	mov    $0x3,%esi
  11:	5d                   	pop    %rbp
  12:	41 5c                	pop    %r12
  14:	41 5d                	pop    %r13
[   71.360293] RSP: 0018:ffffb03c80063d50 EFLAGS: 00010286
[   71.360748] RAX: 0000000000000000 RBX: 00000000ffffffff RCX: 00000000ffffdfff
[   71.361443] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   71.362073] RBP: ffff88a7c4ee3c00 R08: ffffffffa8b78508 R09: 00000000ffffdfff
[   71.362736] R10: ffffffffa8a98520 R11: ffffffffa8b48520 R12: ffff88a7c1fe6000
[   71.363368] R13: ffffb03c80063e08 R14: ffff88a7c1fe6b80 R15: ffff88a7c126ae50
[   71.363965] FS:  0000000000000000(0000) GS:ffff88a7ffd80000(0000) knlGS:0000000000000000
[   71.364696] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   71.365202] CR2: 0000557483ba1e50 CR3: 000000003da60004 CR4: 0000000000770ef0
[   71.365845] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   71.366464] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   71.367086] PKRU: 55555554
[   71.367291] Call Trace:
[   71.367441]  <TASK>
[   71.367560] ? __warn (kernel/panic.c:677) 
[   71.367738] ? kobject_put (lib/kobject.c:730 (discriminator 1)) 
[   71.367969] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[   71.368210] ? handle_bug (arch/x86/kernel/traps.c:238) 
[   71.368401] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[   71.368603] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[   71.368848] ? kobject_put (lib/kobject.c:730 (discriminator 1)) 
[   71.369115] br_sysfs_delbr (net/bridge/br_sysfs_br.c:1086) 
[   71.369416] br_dev_delete (net/bridge/br_if.c:396) 
[   71.369787] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[   71.370048] cleanup_net (net/core/net_namespace.c:630) 
[   71.370358] ? process_one_work (kernel/workqueue.c:2606) 
[   71.370769] process_one_work (kernel/workqueue.c:2633) 
[   71.371255] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[   71.371718] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[   71.372265] kthread (kernel/kthread.c:388) 
[   71.372660] ? __pfx_kthread (kernel/kthread.c:341) 
[   71.373138] ret_from_fork (arch/x86/kernel/process.c:147) 
[   71.373565] ? __pfx_kthread (kernel/kthread.c:341) 
[   71.374066] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   71.379695] ------------[ cut here ]------------
| [   71.380170] sysfs group 'bridge' not found for kobject 'br2'
| [   71.380700] WARNING: CPU: 3 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [   71.381333] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel
[   71.382415] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   71.383191] Workqueue: netns cleanup_net
[   71.383494] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 71.383848] Code: 48 89 ef 5d 41 5c e9 7a ad ff ff 48 89 ef e8 12 9b ff ff eb d1 90 49 8b 14 24 48 8b 33 48 c7 c7 d0 cd 72 a8 e8 ac 67 c5 ff 90 <0f> 0b 90 90 5b 5d 41 5c c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00
All code
========
   0:	48 89 ef             	mov    %rbp,%rdi
   3:	5d                   	pop    %rbp
   4:	41 5c                	pop    %r12
   6:	e9 7a ad ff ff       	jmp    0xffffffffffffad85
   b:	48 89 ef             	mov    %rbp,%rdi
   e:	e8 12 9b ff ff       	call   0xffffffffffff9b25
  13:	eb d1                	jmp    0xffffffffffffffe6
  15:	90                   	nop
  16:	49 8b 14 24          	mov    (%r12),%rdx
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 d0 cd 72 a8 	mov    $0xffffffffa872cdd0,%rdi
  24:	e8 ac 67 c5 ff       	call   0xffffffffffc567d5
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	5b                   	pop    %rbx
  2f:	5d                   	pop    %rbp
  30:	41 5c                	pop    %r12
  32:	c3                   	ret
  33:	cc                   	int3
  34:	cc                   	int3
  35:	cc                   	int3
  36:	cc                   	int3
  37:	66                   	data16
  38:	66                   	data16
  39:	2e                   	cs
  3a:	0f                   	.byte 0xf
  3b:	1f                   	(bad)
  3c:	84 00                	test   %al,(%rax)
	...

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	5b                   	pop    %rbx
   5:	5d                   	pop    %rbp
   6:	41 5c                	pop    %r12
   8:	c3                   	ret
   9:	cc                   	int3
   a:	cc                   	int3
   b:	cc                   	int3
   c:	cc                   	int3
   d:	66                   	data16
   e:	66                   	data16
   f:	2e                   	cs
  10:	0f                   	.byte 0xf
  11:	1f                   	(bad)
  12:	84 00                	test   %al,(%rax)
	...
[   71.385086] RSP: 0018:ffffb03c80063d70 EFLAGS: 00010286
[   71.385582] RAX: 0000000000000000 RBX: ffffffffa83472c0 RCX: 00000000ffffdfff
[   71.386047] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   71.386702] RBP: 0000000000000000 R08: ffffffffa8b78508 R09: 00000000ffffdfff
[   71.387402] R10: ffffffffa8a98520 R11: ffffffffa8b48520 R12: ffff88a7c1fe6610
[   71.388107] R13: ffffb03c80063e08 R14: ffff88a7c1fe6b80 R15: ffff88a7c126ae50
[   71.388824] FS:  0000000000000000(0000) GS:ffff88a7ffd80000(0000) knlGS:0000000000000000
[   71.389695] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   71.390334] CR2: 0000557483ba1e50 CR3: 000000003da60004 CR4: 0000000000770ef0
[   71.391031] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   71.391689] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   71.392357] PKRU: 55555554
[   71.392708] Call Trace:
[   71.392979]  <TASK>
[   71.393190] ? __warn (kernel/panic.c:677) 
[   71.393446] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   71.393842] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[   71.394192] ? handle_bug (arch/x86/kernel/traps.c:238) 
[   71.394532] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[   71.394885] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[   71.395256] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   71.395685] br_dev_delete (net/bridge/br_if.c:396) 
[   71.395961] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[   71.396380] cleanup_net (net/core/net_namespace.c:630) 
[   71.396701] ? process_one_work (kernel/workqueue.c:2606) 
[   71.397094] process_one_work (kernel/workqueue.c:2633) 
[   71.397340] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[   71.397592] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[   71.397893] kthread (kernel/kthread.c:388) 
[   71.398084] ? __pfx_kthread (kernel/kthread.c:341) 
[   71.398317] ret_from_fork (arch/x86/kernel/process.c:147) 
[   71.398535] ? __pfx_kthread (kernel/kthread.c:341) 
[   71.398767] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   71.596088] ------------[ cut here ]------------
| [   71.596542] sysfs group 'bridge' not found for kobject 'br1'
| [   71.597118] WARNING: CPU: 3 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [   71.597976] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel
[   71.599234] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   71.600078] Workqueue: netns cleanup_net
[   71.600578] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 71.601104] Code: 48 89 ef 5d 41 5c e9 7a ad ff ff 48 89 ef e8 12 9b ff ff eb d1 90 49 8b 14 24 48 8b 33 48 c7 c7 d0 cd 72 a8 e8 ac 67 c5 ff 90 <0f> 0b 90 90 5b 5d 41 5c c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00
All code
========
   0:	48 89 ef             	mov    %rbp,%rdi
   3:	5d                   	pop    %rbp
   4:	41 5c                	pop    %r12
   6:	e9 7a ad ff ff       	jmp    0xffffffffffffad85
   b:	48 89 ef             	mov    %rbp,%rdi
   e:	e8 12 9b ff ff       	call   0xffffffffffff9b25
  13:	eb d1                	jmp    0xffffffffffffffe6
  15:	90                   	nop
  16:	49 8b 14 24          	mov    (%r12),%rdx
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 d0 cd 72 a8 	mov    $0xffffffffa872cdd0,%rdi
  24:	e8 ac 67 c5 ff       	call   0xffffffffffc567d5
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	5b                   	pop    %rbx
  2f:	5d                   	pop    %rbp
  30:	41 5c                	pop    %r12
  32:	c3                   	ret
  33:	cc                   	int3
  34:	cc                   	int3
  35:	cc                   	int3
  36:	cc                   	int3
  37:	66                   	data16
  38:	66                   	data16
  39:	2e                   	cs
  3a:	0f                   	.byte 0xf
  3b:	1f                   	(bad)
  3c:	84 00                	test   %al,(%rax)
	...

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	5b                   	pop    %rbx
   5:	5d                   	pop    %rbp
   6:	41 5c                	pop    %r12
   8:	c3                   	ret
   9:	cc                   	int3
   a:	cc                   	int3
   b:	cc                   	int3
   c:	cc                   	int3
   d:	66                   	data16
   e:	66                   	data16
   f:	2e                   	cs
  10:	0f                   	.byte 0xf
  11:	1f                   	(bad)
  12:	84 00                	test   %al,(%rax)
	...
[   71.603626] RSP: 0018:ffffb03c80063d70 EFLAGS: 00010286
[   71.604341] RAX: 0000000000000000 RBX: ffffffffa83472c0 RCX: 00000000ffffdfff
[   71.605127] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   71.605798] RBP: 0000000000000000 R08: ffffffffa8b78508 R09: 00000000ffffdfff
[   71.606394] R10: ffffffffa8a98520 R11: ffffffffa8b48520 R12: ffff88a7c4fa2610
[   71.606957] R13: ffffb03c80063e08 R14: ffff88a7c4fa2b80 R15: ffff88a7c2239750
[   71.607703] FS:  0000000000000000(0000) GS:ffff88a7ffd80000(0000) knlGS:0000000000000000
[   71.608548] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   71.608995] CR2: 0000557483ba1e50 CR3: 000000003da60005 CR4: 0000000000770ef0
[   71.609397] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   71.609838] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   71.610203] PKRU: 55555554
[   71.610353] Call Trace:
[   71.610489]  <TASK>
[   71.610607] ? __warn (kernel/panic.c:677) 
[   71.610791] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   71.611012] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[   71.611210] ? handle_bug (arch/x86/kernel/traps.c:238) 
[   71.611406] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[   71.611610] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[   71.611840] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   71.612063] br_dev_delete (net/bridge/br_if.c:396) 
[   71.612257] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[   71.612527] cleanup_net (net/core/net_namespace.c:630) 
[   71.612722] ? process_one_work (kernel/workqueue.c:2606) 
[   71.612951] process_one_work (kernel/workqueue.c:2633) 
[   71.613165] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[   71.613374] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[   71.613601] kthread (kernel/kthread.c:388) 
[   71.613773] ? __pfx_kthread (kernel/kthread.c:341) 
[   71.613989] ret_from_fork (arch/x86/kernel/process.c:147) 
[   71.614182] ? __pfx_kthread (kernel/kthread.c:341) 
[   71.614389] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   71.616968] ------------[ cut here ]------------
| [   71.617210] sysfs group 'bridge' not found for kobject 'br2'
| [   71.617517] WARNING: CPU: 3 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [   71.617934] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel
[   71.618682] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   71.619277] Workqueue: netns cleanup_net
[   71.619502] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 71.619751] Code: 48 89 ef 5d 41 5c e9 7a ad ff ff 48 89 ef e8 12 9b ff ff eb d1 90 49 8b 14 24 48 8b 33 48 c7 c7 d0 cd 72 a8 e8 ac 67 c5 ff 90 <0f> 0b 90 90 5b 5d 41 5c c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00
All code
========
   0:	48 89 ef             	mov    %rbp,%rdi
   3:	5d                   	pop    %rbp
   4:	41 5c                	pop    %r12
   6:	e9 7a ad ff ff       	jmp    0xffffffffffffad85
   b:	48 89 ef             	mov    %rbp,%rdi
   e:	e8 12 9b ff ff       	call   0xffffffffffff9b25
  13:	eb d1                	jmp    0xffffffffffffffe6
  15:	90                   	nop
  16:	49 8b 14 24          	mov    (%r12),%rdx
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 d0 cd 72 a8 	mov    $0xffffffffa872cdd0,%rdi
  24:	e8 ac 67 c5 ff       	call   0xffffffffffc567d5
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	5b                   	pop    %rbx
  2f:	5d                   	pop    %rbp
  30:	41 5c                	pop    %r12
  32:	c3                   	ret
  33:	cc                   	int3
  34:	cc                   	int3
  35:	cc                   	int3
  36:	cc                   	int3
  37:	66                   	data16
  38:	66                   	data16
  39:	2e                   	cs
  3a:	0f                   	.byte 0xf
  3b:	1f                   	(bad)
  3c:	84 00                	test   %al,(%rax)
	...

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	5b                   	pop    %rbx
   5:	5d                   	pop    %rbp
   6:	41 5c                	pop    %r12
   8:	c3                   	ret
   9:	cc                   	int3
   a:	cc                   	int3
   b:	cc                   	int3
   c:	cc                   	int3
   d:	66                   	data16
   e:	66                   	data16
   f:	2e                   	cs
  10:	0f                   	.byte 0xf
  11:	1f                   	(bad)
  12:	84 00                	test   %al,(%rax)
	...
[   71.620687] RSP: 0018:ffffb03c80063d70 EFLAGS: 00010286
[   71.620966] RAX: 0000000000000000 RBX: ffffffffa83472c0 RCX: 00000000ffffdfff
[   71.621328] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   71.621691] RBP: 0000000000000000 R08: ffffffffa8b78508 R09: 00000000ffffdfff
[   71.622060] R10: ffffffffa8a98520 R11: ffffffffa8b48520 R12: ffff88a7c1fe4610
[   71.622424] R13: ffffb03c80063e08 R14: ffff88a7c1fe4b80 R15: ffff88a7c2239750
[   71.622795] FS:  0000000000000000(0000) GS:ffff88a7ffd80000(0000) knlGS:0000000000000000
[   71.623205] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   71.623501] CR2: 0000557483ba1e50 CR3: 000000003da60005 CR4: 0000000000770ef0
[   71.623870] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   71.624233] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   71.624594] PKRU: 55555554
[   71.624741] Call Trace:
[   71.624879]  <TASK>
[   71.624998] ? __warn (kernel/panic.c:677) 
[   71.625172] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   71.625391] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[   71.625588] ? handle_bug (arch/x86/kernel/traps.c:238) 
[   71.625783] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[   71.625987] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[   71.626213] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   71.626432] br_dev_delete (net/bridge/br_if.c:396) 
[   71.626623] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[   71.626862] cleanup_net (net/core/net_namespace.c:630) 
[   71.627055] ? process_one_work (kernel/workqueue.c:2606) 
[   71.627273] process_one_work (kernel/workqueue.c:2633) 
[   71.627489] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[   71.627689] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[   71.627920] kthread (kernel/kthread.c:388) 
[   71.628090] ? __pfx_kthread (kernel/kthread.c:341) 
[   71.628288] ret_from_fork (arch/x86/kernel/process.c:147) 
[   71.628479] ? __pfx_kthread (kernel/kthread.c:341) 
[   71.628678] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   75.921013] ------------[ cut here ]------------
| [   75.921445] sysfs group 'bridge' not found for kobject 'br1'
| [   75.921891] WARNING: CPU: 1 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [   75.922563] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel
[   75.923728] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   75.924700] Workqueue: netns cleanup_net
[   75.925004] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 75.925260] Code: 48 89 ef 5d 41 5c e9 7a ad ff ff 48 89 ef e8 12 9b ff ff eb d1 90 49 8b 14 24 48 8b 33 48 c7 c7 d0 cd 72 a8 e8 ac 67 c5 ff 90 <0f> 0b 90 90 5b 5d 41 5c c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00
All code
========
   0:	48 89 ef             	mov    %rbp,%rdi
   3:	5d                   	pop    %rbp
   4:	41 5c                	pop    %r12
   6:	e9 7a ad ff ff       	jmp    0xffffffffffffad85
   b:	48 89 ef             	mov    %rbp,%rdi
   e:	e8 12 9b ff ff       	call   0xffffffffffff9b25
  13:	eb d1                	jmp    0xffffffffffffffe6
  15:	90                   	nop
  16:	49 8b 14 24          	mov    (%r12),%rdx
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 d0 cd 72 a8 	mov    $0xffffffffa872cdd0,%rdi
  24:	e8 ac 67 c5 ff       	call   0xffffffffffc567d5
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	5b                   	pop    %rbx
  2f:	5d                   	pop    %rbp
  30:	41 5c                	pop    %r12
  32:	c3                   	ret
  33:	cc                   	int3
  34:	cc                   	int3
  35:	cc                   	int3
  36:	cc                   	int3
  37:	66                   	data16
  38:	66                   	data16
  39:	2e                   	cs
  3a:	0f                   	.byte 0xf
  3b:	1f                   	(bad)
  3c:	84 00                	test   %al,(%rax)
	...

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	5b                   	pop    %rbx
   5:	5d                   	pop    %rbp
   6:	41 5c                	pop    %r12
   8:	c3                   	ret
   9:	cc                   	int3
   a:	cc                   	int3
   b:	cc                   	int3
   c:	cc                   	int3
   d:	66                   	data16
   e:	66                   	data16
   f:	2e                   	cs
  10:	0f                   	.byte 0xf
  11:	1f                   	(bad)
  12:	84 00                	test   %al,(%rax)
	...
[   75.926279] RSP: 0018:ffffb03c80063d70 EFLAGS: 00010286
[   75.926551] RAX: 0000000000000000 RBX: ffffffffa83472c0 RCX: 00000000ffffdfff
[   75.926923] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   75.927287] RBP: 0000000000000000 R08: ffffffffa8b78508 R09: 00000000ffffdfff
[   75.927646] R10: ffffffffa8a98520 R11: ffffffffa8b48520 R12: ffff88a7c21e6610
[   75.928017] R13: ffffb03c80063e08 R14: ffff88a7c21e6b80 R15: ffff88a7c3e4dc50
[   75.928405] FS:  0000000000000000(0000) GS:ffff88a7ffc80000(0000) knlGS:0000000000000000
[   75.928836] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   75.929146] CR2: 00007f023e8b0000 CR3: 000000003da60004 CR4: 0000000000770ef0
[   75.929674] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   75.930129] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   75.930494] PKRU: 55555554
[   75.930638] Call Trace:
[   75.930771]  <TASK>
[   75.930898] ? __warn (kernel/panic.c:677) 
[   75.931074] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   75.931293] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[   75.931488] ? handle_bug (arch/x86/kernel/traps.c:238) 
[   75.931673] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[   75.931884] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[   75.932107] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   75.932328] br_dev_delete (net/bridge/br_if.c:396) 
[   75.932520] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[   75.932751] cleanup_net (net/core/net_namespace.c:630) 
[   75.932951] ? process_one_work (kernel/workqueue.c:2606) 
[   75.933173] process_one_work (kernel/workqueue.c:2633) 
[   75.933387] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[   75.933587] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[   75.933818] kthread (kernel/kthread.c:388) 
[   75.934000] ? __pfx_kthread (kernel/kthread.c:341) 
[   75.934216] ret_from_fork (arch/x86/kernel/process.c:147) 
[   75.934408] ? __pfx_kthread (kernel/kthread.c:341) 
[   75.934605] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   75.937142] ------------[ cut here ]------------
| [   75.937422] sysfs group 'bridge' not found for kobject 'br2'
| [   75.937890] WARNING: CPU: 1 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [   75.938329] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel
[   75.939135] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   75.940123] Workqueue: netns cleanup_net
[   75.940461] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 75.940869] Code: 48 89 ef 5d 41 5c e9 7a ad ff ff 48 89 ef e8 12 9b ff ff eb d1 90 49 8b 14 24 48 8b 33 48 c7 c7 d0 cd 72 a8 e8 ac 67 c5 ff 90 <0f> 0b 90 90 5b 5d 41 5c c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00
All code
========
   0:	48 89 ef             	mov    %rbp,%rdi
   3:	5d                   	pop    %rbp
   4:	41 5c                	pop    %r12
   6:	e9 7a ad ff ff       	jmp    0xffffffffffffad85
   b:	48 89 ef             	mov    %rbp,%rdi
   e:	e8 12 9b ff ff       	call   0xffffffffffff9b25
  13:	eb d1                	jmp    0xffffffffffffffe6
  15:	90                   	nop
  16:	49 8b 14 24          	mov    (%r12),%rdx
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 d0 cd 72 a8 	mov    $0xffffffffa872cdd0,%rdi
  24:	e8 ac 67 c5 ff       	call   0xffffffffffc567d5
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	5b                   	pop    %rbx
  2f:	5d                   	pop    %rbp
  30:	41 5c                	pop    %r12
  32:	c3                   	ret
  33:	cc                   	int3
  34:	cc                   	int3
  35:	cc                   	int3
  36:	cc                   	int3
  37:	66                   	data16
  38:	66                   	data16
  39:	2e                   	cs
  3a:	0f                   	.byte 0xf
  3b:	1f                   	(bad)
  3c:	84 00                	test   %al,(%rax)
	...

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	5b                   	pop    %rbx
   5:	5d                   	pop    %rbp
   6:	41 5c                	pop    %r12
   8:	c3                   	ret
   9:	cc                   	int3
   a:	cc                   	int3
   b:	cc                   	int3
   c:	cc                   	int3
   d:	66                   	data16
   e:	66                   	data16
   f:	2e                   	cs
  10:	0f                   	.byte 0xf
  11:	1f                   	(bad)
  12:	84 00                	test   %al,(%rax)
	...
[   75.942180] RSP: 0018:ffffb03c80063d70 EFLAGS: 00010286
[   75.942660] RAX: 0000000000000000 RBX: ffffffffa83472c0 RCX: 00000000ffffdfff
[   75.943322] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   75.944003] RBP: 0000000000000000 R08: ffffffffa8b78508 R09: 00000000ffffdfff
[   75.944744] R10: ffffffffa8a98520 R11: ffffffffa8b48520 R12: ffff88a7c541e610
[   75.945454] R13: ffffb03c80063e08 R14: ffff88a7c541eb80 R15: ffff88a7c3e4dc50
[   75.946178] FS:  0000000000000000(0000) GS:ffff88a7ffc80000(0000) knlGS:0000000000000000
[   75.946986] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   75.947554] CR2: 00007f023e8b0000 CR3: 000000003da60004 CR4: 0000000000770ef0
[   75.948251] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   75.948739] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   75.949164] PKRU: 55555554
[   75.949343] Call Trace:
[   75.949476]  <TASK>
[   75.949595] ? __warn (kernel/panic.c:677) 
[   75.949772] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   75.950019] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[   75.950229] ? handle_bug (arch/x86/kernel/traps.c:238) 
[   75.950493] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[   75.950823] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[   75.951148] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   75.951370] br_dev_delete (net/bridge/br_if.c:396) 
[   75.951642] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[   75.952006] cleanup_net (net/core/net_namespace.c:630) 
[   75.952349] ? process_one_work (kernel/workqueue.c:2606) 
[   75.952724] process_one_work (kernel/workqueue.c:2633) 
[   75.953104] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[   75.953485] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[   75.953865] kthread (kernel/kthread.c:388) 
[   75.954197] ? __pfx_kthread (kernel/kthread.c:341) 
[   75.954546] ret_from_fork (arch/x86/kernel/process.c:147) 
[   75.954884] ? __pfx_kthread (kernel/kthread.c:341) 
[   75.955216] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   76.134029] ------------[ cut here ]------------
| [   76.134544] sysfs group 'bridge' not found for kobject 'br1'
| [   76.134977] WARNING: CPU: 1 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [   76.135461] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel
[   76.136608] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   76.137260] Workqueue: netns cleanup_net
[   76.137594] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 76.138031] Code: 48 89 ef 5d 41 5c e9 7a ad ff ff 48 89 ef e8 12 9b ff ff eb d1 90 49 8b 14 24 48 8b 33 48 c7 c7 d0 cd 72 a8 e8 ac 67 c5 ff 90 <0f> 0b 90 90 5b 5d 41 5c c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00
All code
========
   0:	48 89 ef             	mov    %rbp,%rdi
   3:	5d                   	pop    %rbp
   4:	41 5c                	pop    %r12
   6:	e9 7a ad ff ff       	jmp    0xffffffffffffad85
   b:	48 89 ef             	mov    %rbp,%rdi
   e:	e8 12 9b ff ff       	call   0xffffffffffff9b25
  13:	eb d1                	jmp    0xffffffffffffffe6
  15:	90                   	nop
  16:	49 8b 14 24          	mov    (%r12),%rdx
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 d0 cd 72 a8 	mov    $0xffffffffa872cdd0,%rdi
  24:	e8 ac 67 c5 ff       	call   0xffffffffffc567d5
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	5b                   	pop    %rbx
  2f:	5d                   	pop    %rbp
  30:	41 5c                	pop    %r12
  32:	c3                   	ret
  33:	cc                   	int3
  34:	cc                   	int3
  35:	cc                   	int3
  36:	cc                   	int3
  37:	66                   	data16
  38:	66                   	data16
  39:	2e                   	cs
  3a:	0f                   	.byte 0xf
  3b:	1f                   	(bad)
  3c:	84 00                	test   %al,(%rax)
	...

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	5b                   	pop    %rbx
   5:	5d                   	pop    %rbp
   6:	41 5c                	pop    %r12
   8:	c3                   	ret
   9:	cc                   	int3
   a:	cc                   	int3
   b:	cc                   	int3
   c:	cc                   	int3
   d:	66                   	data16
   e:	66                   	data16
   f:	2e                   	cs
  10:	0f                   	.byte 0xf
  11:	1f                   	(bad)
  12:	84 00                	test   %al,(%rax)
	...
[   76.139428] RSP: 0018:ffffb03c80063d70 EFLAGS: 00010286
[   76.139951] RAX: 0000000000000000 RBX: ffffffffa83472c0 RCX: 00000000ffffdfff
[   76.140652] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   76.141317] RBP: 0000000000000000 R08: ffffffffa8b78508 R09: 00000000ffffdfff
[   76.142063] R10: ffffffffa8a98520 R11: ffffffffa8b48520 R12: ffff88a7c541a610
[   76.142832] R13: ffffb03c80063e08 R14: ffff88a7c541ab80 R15: ffff88a7c2239750
[   76.143765] FS:  0000000000000000(0000) GS:ffff88a7ffc80000(0000) knlGS:0000000000000000
[   76.144638] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   76.145291] CR2: 00007f023e8b0000 CR3: 000000003da60004 CR4: 0000000000770ef0
[   76.146020] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   76.146787] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   76.147524] PKRU: 55555554
[   76.147798] Call Trace:
[   76.147975]  <TASK>
[   76.148201] ? __warn (kernel/panic.c:677) 
[   76.148540] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   76.148897] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[   76.149276] ? handle_bug (arch/x86/kernel/traps.c:238) 
[   76.149618] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[   76.150045] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[   76.150421] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   76.150860] br_dev_delete (net/bridge/br_if.c:396) 
[   76.151150] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[   76.151628] cleanup_net (net/core/net_namespace.c:630) 
[   76.151966] ? process_one_work (kernel/workqueue.c:2606) 
[   76.152361] process_one_work (kernel/workqueue.c:2633) 
[   76.152579] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[   76.152790] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[   76.153058] kthread (kernel/kthread.c:388) 
[   76.153313] ? __pfx_kthread (kernel/kthread.c:341) 
[   76.153549] ret_from_fork (arch/x86/kernel/process.c:147) 
[   76.153741] ? __pfx_kthread (kernel/kthread.c:341) 
[   76.153953] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   76.156580] ------------[ cut here ]------------
| [   76.156829] sysfs group 'bridge' not found for kobject 'br2'
| [   76.157148] WARNING: CPU: 1 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [   76.157590] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel
[   76.158385] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   76.159063] Workqueue: netns cleanup_net
[   76.159276] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 76.159542] Code: 48 89 ef 5d 41 5c e9 7a ad ff ff 48 89 ef e8 12 9b ff ff eb d1 90 49 8b 14 24 48 8b 33 48 c7 c7 d0 cd 72 a8 e8 ac 67 c5 ff 90 <0f> 0b 90 90 5b 5d 41 5c c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00
All code
========
   0:	48 89 ef             	mov    %rbp,%rdi
   3:	5d                   	pop    %rbp
   4:	41 5c                	pop    %r12
   6:	e9 7a ad ff ff       	jmp    0xffffffffffffad85
   b:	48 89 ef             	mov    %rbp,%rdi
   e:	e8 12 9b ff ff       	call   0xffffffffffff9b25
  13:	eb d1                	jmp    0xffffffffffffffe6
  15:	90                   	nop
  16:	49 8b 14 24          	mov    (%r12),%rdx
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 d0 cd 72 a8 	mov    $0xffffffffa872cdd0,%rdi
  24:	e8 ac 67 c5 ff       	call   0xffffffffffc567d5
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	5b                   	pop    %rbx
  2f:	5d                   	pop    %rbp
  30:	41 5c                	pop    %r12
  32:	c3                   	ret
  33:	cc                   	int3
  34:	cc                   	int3
  35:	cc                   	int3
  36:	cc                   	int3
  37:	66                   	data16
  38:	66                   	data16
  39:	2e                   	cs
  3a:	0f                   	.byte 0xf
  3b:	1f                   	(bad)
  3c:	84 00                	test   %al,(%rax)
	...

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	5b                   	pop    %rbx
   5:	5d                   	pop    %rbp
   6:	41 5c                	pop    %r12
   8:	c3                   	ret
   9:	cc                   	int3
   a:	cc                   	int3
   b:	cc                   	int3
   c:	cc                   	int3
   d:	66                   	data16
   e:	66                   	data16
   f:	2e                   	cs
  10:	0f                   	.byte 0xf
  11:	1f                   	(bad)
  12:	84 00                	test   %al,(%rax)
	...
[   76.160514] RSP: 0018:ffffb03c80063d70 EFLAGS: 00010286
[   76.160807] RAX: 0000000000000000 RBX: ffffffffa83472c0 RCX: 00000000ffffdfff
[   76.161189] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   76.161567] RBP: 0000000000000000 R08: ffffffffa8b78508 R09: 00000000ffffdfff
[   76.161964] R10: ffffffffa8a98520 R11: ffffffffa8b48520 R12: ffff88a7c541c610
[   76.162344] R13: ffffb03c80063e08 R14: ffff88a7c541cb80 R15: ffff88a7c2239750
[   76.162728] FS:  0000000000000000(0000) GS:ffff88a7ffc80000(0000) knlGS:0000000000000000
[   76.163186] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   76.163490] CR2: 00007f023e8b0000 CR3: 000000003da60004 CR4: 0000000000770ef0
[   76.163870] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   76.164236] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   76.164607] PKRU: 55555554
[   76.164755] Call Trace:
[   76.164896]  <TASK>
[   76.165015] ? __warn (kernel/panic.c:677) 
[   76.165194] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   76.165420] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[   76.165622] ? handle_bug (arch/x86/kernel/traps.c:238) 
[   76.165816] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[   76.166021] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[   76.166244] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   76.166466] br_dev_delete (net/bridge/br_if.c:396) 
[   76.166658] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[   76.166908] cleanup_net (net/core/net_namespace.c:630) 
[   76.167110] ? process_one_work (kernel/workqueue.c:2606) 
[   76.167348] process_one_work (kernel/workqueue.c:2633) 
[   76.167570] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[   76.167769] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[   76.168014] kthread (kernel/kthread.c:388) 
[   76.168184] ? __pfx_kthread (kernel/kthread.c:341) 
[   76.168384] ret_from_fork (arch/x86/kernel/process.c:147) 
[   76.168588] ? __pfx_kthread (kernel/kthread.c:341) 
[   76.168799] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   80.649012] ------------[ cut here ]------------
| [   80.649509] sysfs group 'bridge' not found for kobject 'br1'
| [   80.650080] WARNING: CPU: 1 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [   80.650850] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel
[   80.652040] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   80.653230] Workqueue: netns cleanup_net
[   80.653644] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 80.654174] Code: 48 89 ef 5d 41 5c e9 7a ad ff ff 48 89 ef e8 12 9b ff ff eb d1 90 49 8b 14 24 48 8b 33 48 c7 c7 d0 cd 72 a8 e8 ac 67 c5 ff 90 <0f> 0b 90 90 5b 5d 41 5c c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00
All code
========
   0:	48 89 ef             	mov    %rbp,%rdi
   3:	5d                   	pop    %rbp
   4:	41 5c                	pop    %r12
   6:	e9 7a ad ff ff       	jmp    0xffffffffffffad85
   b:	48 89 ef             	mov    %rbp,%rdi
   e:	e8 12 9b ff ff       	call   0xffffffffffff9b25
  13:	eb d1                	jmp    0xffffffffffffffe6
  15:	90                   	nop
  16:	49 8b 14 24          	mov    (%r12),%rdx
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 d0 cd 72 a8 	mov    $0xffffffffa872cdd0,%rdi
  24:	e8 ac 67 c5 ff       	call   0xffffffffffc567d5
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	5b                   	pop    %rbx
  2f:	5d                   	pop    %rbp
  30:	41 5c                	pop    %r12
  32:	c3                   	ret
  33:	cc                   	int3
  34:	cc                   	int3
  35:	cc                   	int3
  36:	cc                   	int3
  37:	66                   	data16
  38:	66                   	data16
  39:	2e                   	cs
  3a:	0f                   	.byte 0xf
  3b:	1f                   	(bad)
  3c:	84 00                	test   %al,(%rax)
	...

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	5b                   	pop    %rbx
   5:	5d                   	pop    %rbp
   6:	41 5c                	pop    %r12
   8:	c3                   	ret
   9:	cc                   	int3
   a:	cc                   	int3
   b:	cc                   	int3
   c:	cc                   	int3
   d:	66                   	data16
   e:	66                   	data16
   f:	2e                   	cs
  10:	0f                   	.byte 0xf
  11:	1f                   	(bad)
  12:	84 00                	test   %al,(%rax)
	...
[   80.656124] RSP: 0018:ffffb03c80063d70 EFLAGS: 00010286
[   80.656722] RAX: 0000000000000000 RBX: ffffffffa83472c0 RCX: 00000000ffffdfff
[   80.657628] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   80.658413] RBP: 0000000000000000 R08: ffffffffa8b78508 R09: 00000000ffffdfff
[   80.659133] R10: ffffffffa8a98520 R11: ffffffffa8b48520 R12: ffff88a7c4fa6610
[   80.659798] R13: ffffb03c80063e08 R14: ffff88a7c4fa6b80 R15: ffff88a7c4cf1750
[   80.660449] FS:  0000000000000000(0000) GS:ffff88a7ffc80000(0000) knlGS:0000000000000000
[   80.660915] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   80.661334] CR2: 0000557483b31428 CR3: 000000003da60001 CR4: 0000000000770ef0
[   80.661733] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   80.662129] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   80.662707] PKRU: 55555554
[   80.663049] Call Trace:
[   80.663295]  <TASK>
[   80.663429] ? __warn (kernel/panic.c:677) 
[   80.663685] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   80.664132] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[   80.664483] ? handle_bug (arch/x86/kernel/traps.c:238) 
[   80.664895] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[   80.665328] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[   80.665729] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   80.666211] br_dev_delete (net/bridge/br_if.c:396) 
[   80.666583] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[   80.667061] cleanup_net (net/core/net_namespace.c:630) 
[   80.667397] ? process_one_work (kernel/workqueue.c:2606) 
[   80.667796] process_one_work (kernel/workqueue.c:2633) 
[   80.668195] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[   80.668616] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[   80.669047] kthread (kernel/kthread.c:388) 
[   80.669477] ? __pfx_kthread (kernel/kthread.c:341) 
[   80.669999] ret_from_fork (arch/x86/kernel/process.c:147) 
[   80.670418] ? __pfx_kthread (kernel/kthread.c:341) 
[   80.670848] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   80.676347] ------------[ cut here ]------------
| [   80.676628] sysfs group 'bridge' not found for kobject 'br2'
| [   80.677113] WARNING: CPU: 2 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [   80.677879] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel
[   80.679244] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   80.680370] Workqueue: netns cleanup_net
[   80.680596] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 80.680869] Code: 48 89 ef 5d 41 5c e9 7a ad ff ff 48 89 ef e8 12 9b ff ff eb d1 90 49 8b 14 24 48 8b 33 48 c7 c7 d0 cd 72 a8 e8 ac 67 c5 ff 90 <0f> 0b 90 90 5b 5d 41 5c c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00
All code
========
   0:	48 89 ef             	mov    %rbp,%rdi
   3:	5d                   	pop    %rbp
   4:	41 5c                	pop    %r12
   6:	e9 7a ad ff ff       	jmp    0xffffffffffffad85
   b:	48 89 ef             	mov    %rbp,%rdi
   e:	e8 12 9b ff ff       	call   0xffffffffffff9b25
  13:	eb d1                	jmp    0xffffffffffffffe6
  15:	90                   	nop
  16:	49 8b 14 24          	mov    (%r12),%rdx
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 d0 cd 72 a8 	mov    $0xffffffffa872cdd0,%rdi
  24:	e8 ac 67 c5 ff       	call   0xffffffffffc567d5
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	5b                   	pop    %rbx
  2f:	5d                   	pop    %rbp
  30:	41 5c                	pop    %r12
  32:	c3                   	ret
  33:	cc                   	int3
  34:	cc                   	int3
  35:	cc                   	int3
  36:	cc                   	int3
  37:	66                   	data16
  38:	66                   	data16
  39:	2e                   	cs
  3a:	0f                   	.byte 0xf
  3b:	1f                   	(bad)
  3c:	84 00                	test   %al,(%rax)
	...

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	5b                   	pop    %rbx
   5:	5d                   	pop    %rbp
   6:	41 5c                	pop    %r12
   8:	c3                   	ret
   9:	cc                   	int3
   a:	cc                   	int3
   b:	cc                   	int3
   c:	cc                   	int3
   d:	66                   	data16
   e:	66                   	data16
   f:	2e                   	cs
  10:	0f                   	.byte 0xf
  11:	1f                   	(bad)
  12:	84 00                	test   %al,(%rax)
	...
[   80.682189] RSP: 0018:ffffb03c80063d70 EFLAGS: 00010286
[   80.682497] RAX: 0000000000000000 RBX: ffffffffa83472c0 RCX: 00000000ffffdfff
[   80.683328] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   80.683868] RBP: 0000000000000000 R08: ffffffffa8b78508 R09: 00000000ffffdfff
[   80.684752] R10: ffffffffa8a98520 R11: ffffffffa8b48520 R12: ffff88a7c3e50610
[   80.685463] R13: ffffb03c80063e08 R14: ffff88a7c3e50b80 R15: ffff88a7c4cf1750
[   80.686392] FS:  0000000000000000(0000) GS:ffff88a7ffd00000(0000) knlGS:0000000000000000
[   80.687272] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   80.687895] CR2: 00007fd26bb6b270 CR3: 000000003da60005 CR4: 0000000000770ef0
[   80.688612] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   80.689366] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   80.690086] PKRU: 55555554
[   80.690370] Call Trace:
[   80.690646]  <TASK>
[   80.690892] ? __warn (kernel/panic.c:677) 
[   80.691258] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   80.691660] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[   80.692064] ? handle_bug (arch/x86/kernel/traps.c:238) 
[   80.692408] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[   80.692803] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[   80.693211] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   80.693626] br_dev_delete (net/bridge/br_if.c:396) 
[   80.693979] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[   80.694356] cleanup_net (net/core/net_namespace.c:630) 
[   80.694758] ? process_one_work (kernel/workqueue.c:2606) 
[   80.695100] process_one_work (kernel/workqueue.c:2633) 
[   80.695508] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[   80.695864] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[   80.696268] kthread (kernel/kthread.c:388) 
[   80.696551] ? __pfx_kthread (kernel/kthread.c:341) 
[   80.696945] ret_from_fork (arch/x86/kernel/process.c:147) 
[   80.697255] ? __pfx_kthread (kernel/kthread.c:341) 
[   80.697610] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   80.872027] ------------[ cut here ]------------
| [   80.872325] sysfs group 'bridge' not found for kobject 'br1'
| [   80.872717] WARNING: CPU: 0 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [   80.873172] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel
[   80.874086] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   80.874784] Workqueue: netns cleanup_net
[   80.875038] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 80.875334] Code: 48 89 ef 5d 41 5c e9 7a ad ff ff 48 89 ef e8 12 9b ff ff eb d1 90 49 8b 14 24 48 8b 33 48 c7 c7 d0 cd 72 a8 e8 ac 67 c5 ff 90 <0f> 0b 90 90 5b 5d 41 5c c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00
All code
========
   0:	48 89 ef             	mov    %rbp,%rdi
   3:	5d                   	pop    %rbp
   4:	41 5c                	pop    %r12
   6:	e9 7a ad ff ff       	jmp    0xffffffffffffad85
   b:	48 89 ef             	mov    %rbp,%rdi
   e:	e8 12 9b ff ff       	call   0xffffffffffff9b25
  13:	eb d1                	jmp    0xffffffffffffffe6
  15:	90                   	nop
  16:	49 8b 14 24          	mov    (%r12),%rdx
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 d0 cd 72 a8 	mov    $0xffffffffa872cdd0,%rdi
  24:	e8 ac 67 c5 ff       	call   0xffffffffffc567d5
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	5b                   	pop    %rbx
  2f:	5d                   	pop    %rbp
  30:	41 5c                	pop    %r12
  32:	c3                   	ret
  33:	cc                   	int3
  34:	cc                   	int3
  35:	cc                   	int3
  36:	cc                   	int3
  37:	66                   	data16
  38:	66                   	data16
  39:	2e                   	cs
  3a:	0f                   	.byte 0xf
  3b:	1f                   	(bad)
  3c:	84 00                	test   %al,(%rax)
	...

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	5b                   	pop    %rbx
   5:	5d                   	pop    %rbp
   6:	41 5c                	pop    %r12
   8:	c3                   	ret
   9:	cc                   	int3
   a:	cc                   	int3
   b:	cc                   	int3
   c:	cc                   	int3
   d:	66                   	data16
   e:	66                   	data16
   f:	2e                   	cs
  10:	0f                   	.byte 0xf
  11:	1f                   	(bad)
  12:	84 00                	test   %al,(%rax)
	...
[   80.876379] RSP: 0018:ffffb03c80063d70 EFLAGS: 00010286
[   80.876714] RAX: 0000000000000000 RBX: ffffffffa83472c0 RCX: 00000000ffffdfff
[   80.877161] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   80.877560] RBP: 0000000000000000 R08: ffffffffa8b78508 R09: 00000000ffffdfff
[   80.878001] R10: ffffffffa8a98520 R11: ffffffffa8b48520 R12: ffff88a7c1932610
[   80.878510] R13: ffffb03c80063e08 R14: ffff88a7c1932b80 R15: ffff88a7c4cf1750
[   80.878972] FS:  0000000000000000(0000) GS:ffff88a7ffc00000(0000) knlGS:0000000000000000
[   80.879417] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   80.879810] CR2: 00007f6e0bee8000 CR3: 000000003da60002 CR4: 0000000000770ef0
[   80.880263] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   80.880692] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   80.881086] PKRU: 55555554
[   80.881303] Call Trace:
[   80.881519]  <TASK>
[   80.881667] ? __warn (kernel/panic.c:677) 
[   80.881915] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   80.882181] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[   80.882465] ? handle_bug (arch/x86/kernel/traps.c:238) 
[   80.882763] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[   80.883033] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[   80.883296] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   80.883570] br_dev_delete (net/bridge/br_if.c:396) 
[   80.883865] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[   80.884191] cleanup_net (net/core/net_namespace.c:630) 
[   80.884467] ? process_one_work (kernel/workqueue.c:2606) 
[   80.884765] process_one_work (kernel/workqueue.c:2633) 
[   80.885075] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[   80.885329] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[   80.885659] kthread (kernel/kthread.c:388) 
[   80.885908] ? __pfx_kthread (kernel/kthread.c:341) 
[   80.886240] ret_from_fork (arch/x86/kernel/process.c:147) 
[   80.886484] ? __pfx_kthread (kernel/kthread.c:341) 
[   80.886751] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   80.889912] ------------[ cut here ]------------
| [   80.890529] sysfs group 'bridge' not found for kobject 'br2'
| [   80.891139] WARNING: CPU: 3 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [   80.891958] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel
[   80.893401] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   80.894519] Workqueue: netns cleanup_net
[   80.894910] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 80.895396] Code: 48 89 ef 5d 41 5c e9 7a ad ff ff 48 89 ef e8 12 9b ff ff eb d1 90 49 8b 14 24 48 8b 33 48 c7 c7 d0 cd 72 a8 e8 ac 67 c5 ff 90 <0f> 0b 90 90 5b 5d 41 5c c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00
All code
========
   0:	48 89 ef             	mov    %rbp,%rdi
   3:	5d                   	pop    %rbp
   4:	41 5c                	pop    %r12
   6:	e9 7a ad ff ff       	jmp    0xffffffffffffad85
   b:	48 89 ef             	mov    %rbp,%rdi
   e:	e8 12 9b ff ff       	call   0xffffffffffff9b25
  13:	eb d1                	jmp    0xffffffffffffffe6
  15:	90                   	nop
  16:	49 8b 14 24          	mov    (%r12),%rdx
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 d0 cd 72 a8 	mov    $0xffffffffa872cdd0,%rdi
  24:	e8 ac 67 c5 ff       	call   0xffffffffffc567d5
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	5b                   	pop    %rbx
  2f:	5d                   	pop    %rbp
  30:	41 5c                	pop    %r12
  32:	c3                   	ret
  33:	cc                   	int3
  34:	cc                   	int3
  35:	cc                   	int3
  36:	cc                   	int3
  37:	66                   	data16
  38:	66                   	data16
  39:	2e                   	cs
  3a:	0f                   	.byte 0xf
  3b:	1f                   	(bad)
  3c:	84 00                	test   %al,(%rax)
	...

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	5b                   	pop    %rbx
   5:	5d                   	pop    %rbp
   6:	41 5c                	pop    %r12
   8:	c3                   	ret
   9:	cc                   	int3
   a:	cc                   	int3
   b:	cc                   	int3
   c:	cc                   	int3
   d:	66                   	data16
   e:	66                   	data16
   f:	2e                   	cs
  10:	0f                   	.byte 0xf
  11:	1f                   	(bad)
  12:	84 00                	test   %al,(%rax)
	...
[   80.897249] RSP: 0018:ffffb03c80063d70 EFLAGS: 00010286
[   80.897815] RAX: 0000000000000000 RBX: ffffffffa83472c0 RCX: 00000000ffffdfff
[   80.898480] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   80.899115] RBP: 0000000000000000 R08: ffffffffa8b78508 R09: 00000000ffffdfff
[   80.899729] R10: ffffffffa8a98520 R11: ffffffffa8b48520 R12: ffff88a7c4fa4610
[   80.900416] R13: ffffb03c80063e08 R14: ffff88a7c4fa4b80 R15: ffff88a7c4cf1750
[   80.901041] FS:  0000000000000000(0000) GS:ffff88a7ffd80000(0000) knlGS:0000000000000000
[   80.901825] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   80.902336] CR2: 000055748232ddec CR3: 00000000025f0003 CR4: 0000000000770ef0
[   80.903040] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   80.903706] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   80.904346] PKRU: 55555554
[   80.904599] Call Trace:
[   80.904886]  <TASK>
[   80.905122] ? __warn (kernel/panic.c:677) 
[   80.905298] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   80.905524] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[   80.905769] ? handle_bug (arch/x86/kernel/traps.c:238) 
[   80.905963] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[   80.906258] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[   80.906576] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   80.906951] br_dev_delete (net/bridge/br_if.c:396) 
[   80.907231] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[   80.907474] cleanup_net (net/core/net_namespace.c:630) 
[   80.907672] ? process_one_work (kernel/workqueue.c:2606) 
[   80.907902] process_one_work (kernel/workqueue.c:2633) 
[   80.908118] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[   80.908329] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[   80.908557] kthread (kernel/kthread.c:388) 
[   80.908736] ? __pfx_kthread (kernel/kthread.c:341) 
[   80.909009] ret_from_fork (arch/x86/kernel/process.c:147) 
[   80.909332] ? __pfx_kthread (kernel/kthread.c:341) 
[   80.909706] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   87.463986] ------------[ cut here ]------------
| [   87.464504] sysfs group 'bridge' not found for kobject 'br1'
| [   87.465191] WARNING: CPU: 3 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [   87.466093] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel
[   87.467532] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   87.468570] Workqueue: netns cleanup_net
[   87.469048] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 87.469521] Code: 48 89 ef 5d 41 5c e9 7a ad ff ff 48 89 ef e8 12 9b ff ff eb d1 90 49 8b 14 24 48 8b 33 48 c7 c7 d0 cd 72 a8 e8 ac 67 c5 ff 90 <0f> 0b 90 90 5b 5d 41 5c c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00
All code
========
   0:	48 89 ef             	mov    %rbp,%rdi
   3:	5d                   	pop    %rbp
   4:	41 5c                	pop    %r12
   6:	e9 7a ad ff ff       	jmp    0xffffffffffffad85
   b:	48 89 ef             	mov    %rbp,%rdi
   e:	e8 12 9b ff ff       	call   0xffffffffffff9b25
  13:	eb d1                	jmp    0xffffffffffffffe6
  15:	90                   	nop
  16:	49 8b 14 24          	mov    (%r12),%rdx
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 d0 cd 72 a8 	mov    $0xffffffffa872cdd0,%rdi
  24:	e8 ac 67 c5 ff       	call   0xffffffffffc567d5
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	5b                   	pop    %rbx
  2f:	5d                   	pop    %rbp
  30:	41 5c                	pop    %r12
  32:	c3                   	ret
  33:	cc                   	int3
  34:	cc                   	int3
  35:	cc                   	int3
  36:	cc                   	int3
  37:	66                   	data16
  38:	66                   	data16
  39:	2e                   	cs
  3a:	0f                   	.byte 0xf
  3b:	1f                   	(bad)
  3c:	84 00                	test   %al,(%rax)
	...

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	5b                   	pop    %rbx
   5:	5d                   	pop    %rbp
   6:	41 5c                	pop    %r12
   8:	c3                   	ret
   9:	cc                   	int3
   a:	cc                   	int3
   b:	cc                   	int3
   c:	cc                   	int3
   d:	66                   	data16
   e:	66                   	data16
   f:	2e                   	cs
  10:	0f                   	.byte 0xf
  11:	1f                   	(bad)
  12:	84 00                	test   %al,(%rax)
	...
[   87.471087] RSP: 0018:ffffb03c80063d70 EFLAGS: 00010286
[   87.471437] RAX: 0000000000000000 RBX: ffffffffa83472c0 RCX: 00000000ffffdfff
[   87.471846] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   87.472224] RBP: 0000000000000000 R08: ffffffffa8b78508 R09: 00000000ffffdfff
[   87.472609] R10: ffffffffa8a98520 R11: ffffffffa8b48520 R12: ffff88a7c1fe4610
[   87.472998] R13: ffffb03c80063e08 R14: ffff88a7c1fe4b80 R15: ffff88a7c223c550
[   87.473376] FS:  0000000000000000(0000) GS:ffff88a7ffd80000(0000) knlGS:0000000000000000
[   87.473846] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   87.474160] CR2: 00007fe62a9b5c08 CR3: 0000000002436003 CR4: 0000000000770ef0
[   87.474542] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   87.474932] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   87.475295] PKRU: 55555554
[   87.475440] Call Trace:
[   87.475587]  <TASK>
[   87.475711] ? __warn (kernel/panic.c:677) 
[   87.475913] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   87.476148] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[   87.476351] ? handle_bug (arch/x86/kernel/traps.c:238) 
[   87.476544] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[   87.476761] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[   87.477029] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   87.477261] br_dev_delete (net/bridge/br_if.c:396) 
[   87.477465] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[   87.477698] cleanup_net (net/core/net_namespace.c:630) 
[   87.477914] ? process_one_work (kernel/workqueue.c:2606) 
[   87.478146] process_one_work (kernel/workqueue.c:2633) 
[   87.478383] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[   87.478585] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[   87.478832] kthread (kernel/kthread.c:388) 
[   87.479005] ? __pfx_kthread (kernel/kthread.c:341) 
[   87.479204] ret_from_fork (arch/x86/kernel/process.c:147) 
[   87.479409] ? __pfx_kthread (kernel/kthread.c:341) 
[   87.479606] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   87.482211] ------------[ cut here ]------------
| [   87.482503] kobject: '' (0000000048742cf5): is not initialized, yet kobject_put() is being called.
| [   87.483285] WARNING: CPU: 3 PID: 11 at lib/kobject.c:730 kobject_put (lib/kobject.c:730 (discriminator 1)) 
| [   87.483668] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel
[   87.484560] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   87.485707] Workqueue: netns cleanup_net
[   87.486079] RIP: 0010:kobject_put (lib/kobject.c:730 (discriminator 1)) 
[ 87.486372] Code: 89 ef e8 fe ad 4f ff 4d 85 e4 74 c0 4c 89 e5 f6 45 3c 01 75 a3 90 48 8b 75 00 48 89 ea 48 c7 c7 88 ce 7a a8 e8 dc 42 2a ff 90 <0f> 0b 90 90 eb 88 c3 cc cc cc cc 5b be 03 00 00 00 5d 41 5c 41 5d
All code
========
   0:	89 ef                	mov    %ebp,%edi
   2:	e8 fe ad 4f ff       	call   0xffffffffff4fae05
   7:	4d 85 e4             	test   %r12,%r12
   a:	74 c0                	je     0xffffffffffffffcc
   c:	4c 89 e5             	mov    %r12,%rbp
   f:	f6 45 3c 01          	testb  $0x1,0x3c(%rbp)
  13:	75 a3                	jne    0xffffffffffffffb8
  15:	90                   	nop
  16:	48 8b 75 00          	mov    0x0(%rbp),%rsi
  1a:	48 89 ea             	mov    %rbp,%rdx
  1d:	48 c7 c7 88 ce 7a a8 	mov    $0xffffffffa87ace88,%rdi
  24:	e8 dc 42 2a ff       	call   0xffffffffff2a4305
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	eb 88                	jmp    0xffffffffffffffb8
  30:	c3                   	ret
  31:	cc                   	int3
  32:	cc                   	int3
  33:	cc                   	int3
  34:	cc                   	int3
  35:	5b                   	pop    %rbx
  36:	be 03 00 00 00       	mov    $0x3,%esi
  3b:	5d                   	pop    %rbp
  3c:	41 5c                	pop    %r12
  3e:	41 5d                	pop    %r13

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	eb 88                	jmp    0xffffffffffffff8e
   6:	c3                   	ret
   7:	cc                   	int3
   8:	cc                   	int3
   9:	cc                   	int3
   a:	cc                   	int3
   b:	5b                   	pop    %rbx
   c:	be 03 00 00 00       	mov    $0x3,%esi
  11:	5d                   	pop    %rbp
  12:	41 5c                	pop    %r12
  14:	41 5d                	pop    %r13
[   87.487844] RSP: 0018:ffffb03c80063d50 EFLAGS: 00010286
[   87.488296] RAX: 0000000000000000 RBX: 00000000ffffffff RCX: 00000000ffffdfff
[   87.488999] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   87.489749] RBP: ffff88a7c4d67d00 R08: ffffffffa8b78508 R09: 00000000ffffdfff
[   87.490546] R10: ffffffffa8a98520 R11: ffffffffa8b48520 R12: ffff88a7c3da0000
[   87.491247] R13: ffffb03c80063e08 R14: ffff88a7c3da0b80 R15: ffff88a7c223c550
[   87.491914] FS:  0000000000000000(0000) GS:ffff88a7ffd80000(0000) knlGS:0000000000000000
[   87.493048] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   87.493918] CR2: 00007fe62a9b5c08 CR3: 0000000002436003 CR4: 0000000000770ef0
[   87.494989] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   87.496062] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   87.496927] PKRU: 55555554
[   87.497141] Call Trace:
[   87.497382]  <TASK>
[   87.497593] ? __warn (kernel/panic.c:677) 
[   87.497862] ? kobject_put (lib/kobject.c:730 (discriminator 1)) 
[   87.498147] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[   87.498439] ? handle_bug (arch/x86/kernel/traps.c:238) 
[   87.499103] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[   87.499648] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[   87.500014] ? kobject_put (lib/kobject.c:730 (discriminator 1)) 
[   87.500591] br_sysfs_delbr (net/bridge/br_sysfs_br.c:1086) 
[   87.501324] br_dev_delete (net/bridge/br_if.c:396) 
[   87.502004] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[   87.502734] cleanup_net (net/core/net_namespace.c:630) 
[   87.503329] ? process_one_work (kernel/workqueue.c:2606) 
[   87.503830] process_one_work (kernel/workqueue.c:2633) 
[   87.504276] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[   87.504694] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[   87.505122] kthread (kernel/kthread.c:388) 
[   87.505431] ? __pfx_kthread (kernel/kthread.c:341) 
[   87.505891] ret_from_fork (arch/x86/kernel/process.c:147) 
[   87.506273] ? __pfx_kthread (kernel/kthread.c:341) 
[   87.506701] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   87.511522] ------------[ cut here ]------------
| [   87.512067] sysfs group 'bridge' not found for kobject 'br2'
| [   87.512660] WARNING: CPU: 3 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [   87.513375] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel
[   87.514819] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   87.516028] Workqueue: netns cleanup_net
[   87.516541] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 87.516935] Code: 48 89 ef 5d 41 5c e9 7a ad ff ff 48 89 ef e8 12 9b ff ff eb d1 90 49 8b 14 24 48 8b 33 48 c7 c7 d0 cd 72 a8 e8 ac 67 c5 ff 90 <0f> 0b 90 90 5b 5d 41 5c c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00
All code
========
   0:	48 89 ef             	mov    %rbp,%rdi
   3:	5d                   	pop    %rbp
   4:	41 5c                	pop    %r12
   6:	e9 7a ad ff ff       	jmp    0xffffffffffffad85
   b:	48 89 ef             	mov    %rbp,%rdi
   e:	e8 12 9b ff ff       	call   0xffffffffffff9b25
  13:	eb d1                	jmp    0xffffffffffffffe6
  15:	90                   	nop
  16:	49 8b 14 24          	mov    (%r12),%rdx
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 d0 cd 72 a8 	mov    $0xffffffffa872cdd0,%rdi
  24:	e8 ac 67 c5 ff       	call   0xffffffffffc567d5
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	5b                   	pop    %rbx
  2f:	5d                   	pop    %rbp
  30:	41 5c                	pop    %r12
  32:	c3                   	ret
  33:	cc                   	int3
  34:	cc                   	int3
  35:	cc                   	int3
  36:	cc                   	int3
  37:	66                   	data16
  38:	66                   	data16
  39:	2e                   	cs
  3a:	0f                   	.byte 0xf
  3b:	1f                   	(bad)
  3c:	84 00                	test   %al,(%rax)
	...

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	5b                   	pop    %rbx
   5:	5d                   	pop    %rbp
   6:	41 5c                	pop    %r12
   8:	c3                   	ret
   9:	cc                   	int3
   a:	cc                   	int3
   b:	cc                   	int3
   c:	cc                   	int3
   d:	66                   	data16
   e:	66                   	data16
   f:	2e                   	cs
  10:	0f                   	.byte 0xf
  11:	1f                   	(bad)
  12:	84 00                	test   %al,(%rax)
	...
[   87.518737] RSP: 0018:ffffb03c80063d70 EFLAGS: 00010286
[   87.519224] RAX: 0000000000000000 RBX: ffffffffa83472c0 RCX: 00000000ffffdfff
[   87.520070] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   87.521068] RBP: 0000000000000000 R08: ffffffffa8b78508 R09: 00000000ffffdfff
[   87.522002] R10: ffffffffa8a98520 R11: ffffffffa8b48520 R12: ffff88a7c3da0610
[   87.522967] R13: ffffb03c80063e08 R14: ffff88a7c3da0b80 R15: ffff88a7c223c550
[   87.523857] FS:  0000000000000000(0000) GS:ffff88a7ffd80000(0000) knlGS:0000000000000000
[   87.524878] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   87.525365] CR2: 00007fe62a9b5c08 CR3: 0000000002436003 CR4: 0000000000770ef0
[   87.526022] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   87.526658] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   87.527345] PKRU: 55555554
[   87.527619] Call Trace:
[   87.527839]  <TASK>
[   87.528028] ? __warn (kernel/panic.c:677) 
[   87.528320] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   87.528768] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[   87.529084] ? handle_bug (arch/x86/kernel/traps.c:238) 
[   87.529449] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[   87.529762] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[   87.530098] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   87.530458] br_dev_delete (net/bridge/br_if.c:396) 
[   87.530736] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[   87.531092] cleanup_net (net/core/net_namespace.c:630) 
[   87.531439] ? process_one_work (kernel/workqueue.c:2606) 
[   87.531772] process_one_work (kernel/workqueue.c:2633) 
[   87.532159] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[   87.532502] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[   87.532924] kthread (kernel/kthread.c:388) 
[   87.533184] ? __pfx_kthread (kernel/kthread.c:341) 
[   87.533497] ret_from_fork (arch/x86/kernel/process.c:147) 
[   87.533857] ? __pfx_kthread (kernel/kthread.c:341) 
[   87.534192] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   87.537287] ------------[ cut here ]------------
| [   87.537560] sysfs group 'bridge' not found for kobject 'br3'
| [   87.537932] WARNING: CPU: 3 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [   87.538569] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel
[   87.539335] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   87.540305] Workqueue: netns cleanup_net
[   87.540734] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 87.541342] Code: 48 89 ef 5d 41 5c e9 7a ad ff ff 48 89 ef e8 12 9b ff ff eb d1 90 49 8b 14 24 48 8b 33 48 c7 c7 d0 cd 72 a8 e8 ac 67 c5 ff 90 <0f> 0b 90 90 5b 5d 41 5c c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00
All code
========
   0:	48 89 ef             	mov    %rbp,%rdi
   3:	5d                   	pop    %rbp
   4:	41 5c                	pop    %r12
   6:	e9 7a ad ff ff       	jmp    0xffffffffffffad85
   b:	48 89 ef             	mov    %rbp,%rdi
   e:	e8 12 9b ff ff       	call   0xffffffffffff9b25
  13:	eb d1                	jmp    0xffffffffffffffe6
  15:	90                   	nop
  16:	49 8b 14 24          	mov    (%r12),%rdx
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 d0 cd 72 a8 	mov    $0xffffffffa872cdd0,%rdi
  24:	e8 ac 67 c5 ff       	call   0xffffffffffc567d5
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	5b                   	pop    %rbx
  2f:	5d                   	pop    %rbp
  30:	41 5c                	pop    %r12
  32:	c3                   	ret
  33:	cc                   	int3
  34:	cc                   	int3
  35:	cc                   	int3
  36:	cc                   	int3
  37:	66                   	data16
  38:	66                   	data16
  39:	2e                   	cs
  3a:	0f                   	.byte 0xf
  3b:	1f                   	(bad)
  3c:	84 00                	test   %al,(%rax)
	...

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	5b                   	pop    %rbx
   5:	5d                   	pop    %rbp
   6:	41 5c                	pop    %r12
   8:	c3                   	ret
   9:	cc                   	int3
   a:	cc                   	int3
   b:	cc                   	int3
   c:	cc                   	int3
   d:	66                   	data16
   e:	66                   	data16
   f:	2e                   	cs
  10:	0f                   	.byte 0xf
  11:	1f                   	(bad)
  12:	84 00                	test   %al,(%rax)
	...
[   87.542994] RSP: 0018:ffffb03c80063d70 EFLAGS: 00010286
[   87.543445] RAX: 0000000000000000 RBX: ffffffffa83472c0 RCX: 00000000ffffdfff
[   87.543884] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   87.544447] RBP: 0000000000000000 R08: ffffffffa8b78508 R09: 00000000ffffdfff
[   87.545184] R10: ffffffffa8a98520 R11: ffffffffa8b48520 R12: ffff88a7c3da2610
[   87.546200] R13: ffffb03c80063e08 R14: ffff88a7c3da2b80 R15: ffff88a7c223c550
[   87.547270] FS:  0000000000000000(0000) GS:ffff88a7ffd80000(0000) knlGS:0000000000000000
[   87.548461] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   87.549167] CR2: 00007fe62a9b5c08 CR3: 0000000002436003 CR4: 0000000000770ef0
[   87.550251] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   87.551299] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   87.552382] PKRU: 55555554
[   87.552787] Call Trace:
[   87.552991]  <TASK>
[   87.553170] ? __warn (kernel/panic.c:677) 
[   87.553540] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   87.553883] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[   87.554182] ? handle_bug (arch/x86/kernel/traps.c:238) 
[   87.554468] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[   87.554788] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[   87.555371] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   87.556013] br_dev_delete (net/bridge/br_if.c:396) 
[   87.556312] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[   87.556870] cleanup_net (net/core/net_namespace.c:630) 
[   87.557348] ? process_one_work (kernel/workqueue.c:2606) 
[   87.558036] process_one_work (kernel/workqueue.c:2633) 
[   87.558646] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[   87.559209] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[   87.559761] kthread (kernel/kthread.c:388) 
[   87.560024] ? __pfx_kthread (kernel/kthread.c:341) 
[   87.560439] ret_from_fork (arch/x86/kernel/process.c:147) 
[   87.560939] ? __pfx_kthread (kernel/kthread.c:341) 
[   87.561468] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   87.875107] ------------[ cut here ]------------
| [   87.875643] sysfs group 'bridge' not found for kobject 'br1'
| [   87.876107] WARNING: CPU: 3 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [   87.876805] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel
[   87.878767] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   87.880364] Workqueue: netns cleanup_net
[   87.880911] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 87.881557] Code: 48 89 ef 5d 41 5c e9 7a ad ff ff 48 89 ef e8 12 9b ff ff eb d1 90 49 8b 14 24 48 8b 33 48 c7 c7 d0 cd 72 a8 e8 ac 67 c5 ff 90 <0f> 0b 90 90 5b 5d 41 5c c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00
All code
========
   0:	48 89 ef             	mov    %rbp,%rdi
   3:	5d                   	pop    %rbp
   4:	41 5c                	pop    %r12
   6:	e9 7a ad ff ff       	jmp    0xffffffffffffad85
   b:	48 89 ef             	mov    %rbp,%rdi
   e:	e8 12 9b ff ff       	call   0xffffffffffff9b25
  13:	eb d1                	jmp    0xffffffffffffffe6
  15:	90                   	nop
  16:	49 8b 14 24          	mov    (%r12),%rdx
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 d0 cd 72 a8 	mov    $0xffffffffa872cdd0,%rdi
  24:	e8 ac 67 c5 ff       	call   0xffffffffffc567d5
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	5b                   	pop    %rbx
  2f:	5d                   	pop    %rbp
  30:	41 5c                	pop    %r12
  32:	c3                   	ret
  33:	cc                   	int3
  34:	cc                   	int3
  35:	cc                   	int3
  36:	cc                   	int3
  37:	66                   	data16
  38:	66                   	data16
  39:	2e                   	cs
  3a:	0f                   	.byte 0xf
  3b:	1f                   	(bad)
  3c:	84 00                	test   %al,(%rax)
	...

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	5b                   	pop    %rbx
   5:	5d                   	pop    %rbp
   6:	41 5c                	pop    %r12
   8:	c3                   	ret
   9:	cc                   	int3
   a:	cc                   	int3
   b:	cc                   	int3
   c:	cc                   	int3
   d:	66                   	data16
   e:	66                   	data16
   f:	2e                   	cs
  10:	0f                   	.byte 0xf
  11:	1f                   	(bad)
  12:	84 00                	test   %al,(%rax)
	...
[   87.883911] RSP: 0018:ffffb03c80063d70 EFLAGS: 00010286
[   87.884618] RAX: 0000000000000000 RBX: ffffffffa83472c0 RCX: 00000000ffffdfff
[   87.885549] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   87.886265] RBP: 0000000000000000 R08: ffffffffa8b78508 R09: 00000000ffffdfff
[   87.886988] R10: ffffffffa8a98520 R11: ffffffffa8b48520 R12: ffff88a7c3e50610
[   87.887705] R13: ffffb03c80063e08 R14: ffff88a7c3e50b80 R15: ffff88a7c2239750
[   87.888440] FS:  0000000000000000(0000) GS:ffff88a7ffd80000(0000) knlGS:0000000000000000
[   87.889275] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   87.889909] CR2: 00007fe62a9b5c08 CR3: 0000000002436003 CR4: 0000000000770ef0
[   87.890629] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   87.891145] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   87.891616] PKRU: 55555554
[   87.891799] Call Trace:
[   87.892029]  <TASK>
[   87.892172] ? __warn (kernel/panic.c:677) 
[   87.892449] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   87.892885] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[   87.893126] ? handle_bug (arch/x86/kernel/traps.c:238) 
[   87.893359] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[   87.893607] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[   87.893889] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   87.894315] br_dev_delete (net/bridge/br_if.c:396) 
[   87.894731] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[   87.895272] cleanup_net (net/core/net_namespace.c:630) 
[   87.895633] ? process_one_work (kernel/workqueue.c:2606) 
[   87.895907] process_one_work (kernel/workqueue.c:2633) 
[   87.896320] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[   87.896745] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[   87.897265] kthread (kernel/kthread.c:388) 
[   87.897472] ? __pfx_kthread (kernel/kthread.c:341) 
[   87.897890] ret_from_fork (arch/x86/kernel/process.c:147) 
[   87.898273] ? __pfx_kthread (kernel/kthread.c:341) 
[   87.898695] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   87.904500] ------------[ cut here ]------------
| [   87.905076] sysfs group 'bridge' not found for kobject 'br2'
| [   87.905840] WARNING: CPU: 3 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [   87.906839] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel
[   87.908445] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   87.909261] Workqueue: netns cleanup_net
[   87.909514] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 87.909824] Code: 48 89 ef 5d 41 5c e9 7a ad ff ff 48 89 ef e8 12 9b ff ff eb d1 90 49 8b 14 24 48 8b 33 48 c7 c7 d0 cd 72 a8 e8 ac 67 c5 ff 90 <0f> 0b 90 90 5b 5d 41 5c c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00
All code
========
   0:	48 89 ef             	mov    %rbp,%rdi
   3:	5d                   	pop    %rbp
   4:	41 5c                	pop    %r12
   6:	e9 7a ad ff ff       	jmp    0xffffffffffffad85
   b:	48 89 ef             	mov    %rbp,%rdi
   e:	e8 12 9b ff ff       	call   0xffffffffffff9b25
  13:	eb d1                	jmp    0xffffffffffffffe6
  15:	90                   	nop
  16:	49 8b 14 24          	mov    (%r12),%rdx
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 d0 cd 72 a8 	mov    $0xffffffffa872cdd0,%rdi
  24:	e8 ac 67 c5 ff       	call   0xffffffffffc567d5
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	5b                   	pop    %rbx
  2f:	5d                   	pop    %rbp
  30:	41 5c                	pop    %r12
  32:	c3                   	ret
  33:	cc                   	int3
  34:	cc                   	int3
  35:	cc                   	int3
  36:	cc                   	int3
  37:	66                   	data16
  38:	66                   	data16
  39:	2e                   	cs
  3a:	0f                   	.byte 0xf
  3b:	1f                   	(bad)
  3c:	84 00                	test   %al,(%rax)
	...

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	5b                   	pop    %rbx
   5:	5d                   	pop    %rbp
   6:	41 5c                	pop    %r12
   8:	c3                   	ret
   9:	cc                   	int3
   a:	cc                   	int3
   b:	cc                   	int3
   c:	cc                   	int3
   d:	66                   	data16
   e:	66                   	data16
   f:	2e                   	cs
  10:	0f                   	.byte 0xf
  11:	1f                   	(bad)
  12:	84 00                	test   %al,(%rax)
	...
[   87.911088] RSP: 0018:ffffb03c80063d70 EFLAGS: 00010286
[   87.911683] RAX: 0000000000000000 RBX: ffffffffa83472c0 RCX: 00000000ffffdfff
[   87.912261] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   87.913106] RBP: 0000000000000000 R08: ffffffffa8b78508 R09: 00000000ffffdfff
[   87.913957] R10: ffffffffa8a98520 R11: ffffffffa8b48520 R12: ffff88a7c1932610
[   87.914797] R13: ffffb03c80063e08 R14: ffff88a7c1932b80 R15: ffff88a7c2239750
[   87.915666] FS:  0000000000000000(0000) GS:ffff88a7ffd80000(0000) knlGS:0000000000000000
[   87.916652] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   87.917363] CR2: 00007fe62a9b5c08 CR3: 0000000002436003 CR4: 0000000000770ef0
[   87.918222] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   87.919021] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   87.919872] PKRU: 55555554
[   87.920182] Call Trace:
[   87.920500]  <TASK>
[   87.920755] ? __warn (kernel/panic.c:677) 
[   87.921112] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   87.921516] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[   87.921937] ? handle_bug (arch/x86/kernel/traps.c:238) 
[   87.922281] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[   87.922695] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[   87.923158] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   87.923560] br_dev_delete (net/bridge/br_if.c:396) 
[   87.923992] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[   87.924453] cleanup_net (net/core/net_namespace.c:630) 
[   87.924934] ? process_one_work (kernel/workqueue.c:2606) 
[   87.925382] process_one_work (kernel/workqueue.c:2633) 
[   87.925764] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[   87.926018] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[   87.926321] kthread (kernel/kthread.c:388) 
[   87.926561] ? __pfx_kthread (kernel/kthread.c:341) 
[   87.926874] ret_from_fork (arch/x86/kernel/process.c:147) 
[   87.927133] ? __pfx_kthread (kernel/kthread.c:341) 
[   87.927590] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   87.931689] ------------[ cut here ]------------
| [   87.932287] sysfs group 'bridge' not found for kobject 'br3'
| [   87.932925] WARNING: CPU: 3 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [   87.933885] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel
[   87.935535] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   87.936764] Workqueue: netns cleanup_net
[   87.937209] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 87.937764] Code: 48 89 ef 5d 41 5c e9 7a ad ff ff 48 89 ef e8 12 9b ff ff eb d1 90 49 8b 14 24 48 8b 33 48 c7 c7 d0 cd 72 a8 e8 ac 67 c5 ff 90 <0f> 0b 90 90 5b 5d 41 5c c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00
All code
========
   0:	48 89 ef             	mov    %rbp,%rdi
   3:	5d                   	pop    %rbp
   4:	41 5c                	pop    %r12
   6:	e9 7a ad ff ff       	jmp    0xffffffffffffad85
   b:	48 89 ef             	mov    %rbp,%rdi
   e:	e8 12 9b ff ff       	call   0xffffffffffff9b25
  13:	eb d1                	jmp    0xffffffffffffffe6
  15:	90                   	nop
  16:	49 8b 14 24          	mov    (%r12),%rdx
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 d0 cd 72 a8 	mov    $0xffffffffa872cdd0,%rdi
  24:	e8 ac 67 c5 ff       	call   0xffffffffffc567d5
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	5b                   	pop    %rbx
  2f:	5d                   	pop    %rbp
  30:	41 5c                	pop    %r12
  32:	c3                   	ret
  33:	cc                   	int3
  34:	cc                   	int3
  35:	cc                   	int3
  36:	cc                   	int3
  37:	66                   	data16
  38:	66                   	data16
  39:	2e                   	cs
  3a:	0f                   	.byte 0xf
  3b:	1f                   	(bad)
  3c:	84 00                	test   %al,(%rax)
	...

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	5b                   	pop    %rbx
   5:	5d                   	pop    %rbp
   6:	41 5c                	pop    %r12
   8:	c3                   	ret
   9:	cc                   	int3
   a:	cc                   	int3
   b:	cc                   	int3
   c:	cc                   	int3
   d:	66                   	data16
   e:	66                   	data16
   f:	2e                   	cs
  10:	0f                   	.byte 0xf
  11:	1f                   	(bad)
  12:	84 00                	test   %al,(%rax)
	...
[   87.939770] RSP: 0018:ffffb03c80063d70 EFLAGS: 00010286
[   87.940381] RAX: 0000000000000000 RBX: ffffffffa83472c0 RCX: 00000000ffffdfff
[   87.941140] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[   87.941856] RBP: 0000000000000000 R08: ffffffffa8b78508 R09: 00000000ffffdfff
[   87.942531] R10: ffffffffa8a98520 R11: ffffffffa8b48520 R12: ffff88a7c3e52610
[   87.943244] R13: ffffb03c80063e08 R14: ffff88a7c3e52b80 R15: ffff88a7c2239750
[   87.944067] FS:  0000000000000000(0000) GS:ffff88a7ffd80000(0000) knlGS:0000000000000000
[   87.944891] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   87.945488] CR2: 00007fe62a9b5c08 CR3: 0000000002436003 CR4: 0000000000770ef0
[   87.946186] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   87.946937] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   87.947559] PKRU: 55555554
[   87.947734] Call Trace:
[   87.947903]  <TASK>
[   87.948080] ? __warn (kernel/panic.c:677) 
[   87.948290] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   87.948623] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[   87.948881] ? handle_bug (arch/x86/kernel/traps.c:238) 
[   87.949209] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[   87.949663] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[   87.949941] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[   87.950212] br_dev_delete (net/bridge/br_if.c:396) 
[   87.950443] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[   87.950747] cleanup_net (net/core/net_namespace.c:630) 
[   87.951137] ? process_one_work (kernel/workqueue.c:2606) 
[   87.951582] process_one_work (kernel/workqueue.c:2633) 
[   87.952015] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[   87.952443] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[   87.952753] kthread (kernel/kthread.c:388) 
[   87.952966] ? __pfx_kthread (kernel/kthread.c:341) 
[   87.953357] ret_from_fork (arch/x86/kernel/process.c:147) 
[   87.953745] ? __pfx_kthread (kernel/kthread.c:341) 


Finger prints:
refcount_warn_saturate:br_sysfs_delbr:br_dev_delete:br_net_exit_batch_rtnl
sysfs_remove_group:br_dev_delete:br_net_exit_batch_rtnl:cleanup_net
sysfs_remove_group:br_dev_delete:br_net_exit_batch_rtnl:cleanup_net
sysfs_remove_group:br_dev_delete:br_net_exit_batch_rtnl:cleanup_net
sysfs_remove_group:br_dev_delete:br_net_exit_batch_rtnl:cleanup_net
sysfs_remove_group:br_dev_delete:br_net_exit_batch_rtnl:cleanup_net
kobject_put:br_sysfs_delbr:br_dev_delete:br_net_exit_batch_rtnl
sysfs_remove_group:br_dev_delete:br_net_exit_batch_rtnl:cleanup_net
sysfs_remove_group:br_dev_delete:br_net_exit_batch_rtnl:cleanup_net
sysfs_remove_group:br_dev_delete:br_net_exit_batch_rtnl:cleanup_net
sysfs_remove_group:br_dev_delete:br_net_exit_batch_rtnl:cleanup_net
sysfs_remove_group:br_dev_delete:br_net_exit_batch_rtnl:cleanup_net
sysfs_remove_group:br_dev_delete:br_net_exit_batch_rtnl:cleanup_net
sysfs_remove_group:br_dev_delete:br_net_exit_batch_rtnl:cleanup_net
sysfs_remove_group:br_dev_delete:br_net_exit_batch_rtnl:cleanup_net
sysfs_remove_group:br_dev_delete:br_net_exit_batch_rtnl:cleanup_net
sysfs_remove_group:br_dev_delete:br_net_exit_batch_rtnl:cleanup_net
sysfs_remove_group:br_dev_delete:br_net_exit_batch_rtnl:cleanup_net
sysfs_remove_group:br_dev_delete:br_net_exit_batch_rtnl:cleanup_net
kobject_put:br_sysfs_delbr:br_dev_delete:br_net_exit_batch_rtnl
sysfs_remove_group:br_dev_delete:br_net_exit_batch_rtnl:cleanup_net
sysfs_remove_group:br_dev_delete:br_net_exit_batch_rtnl:cleanup_net
sysfs_remove_group:br_dev_delete:br_net_exit_batch_rtnl:cleanup_net
sysfs_remove_group:br_dev_delete:br_net_exit_batch_rtnl:cleanup_net
sysfs_remove_group:br_dev_delete:br_net_exit_batch_rtnl:cleanup_net