======================================
| [   40.022460][   T11] ==================================================================
| [ 40.022903][ T11] BUG: KASAN: slab-use-after-free in kobject_put (lib/kobject.c:729) 
| [   40.023305][   T11] Read of size 1 at addr ffff88800200a6bc by task kworker/u8:0/11
| [   40.023718][   T11]
[   40.024263][   T11] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   40.024902][   T11] Workqueue: netns cleanup_net
[   40.025157][   T11] Call Trace:
[   40.025339][   T11]  <TASK>
[ 40.025500][ T11] dump_stack_lvl (lib/dump_stack.c:107) 
[ 40.025743][ T11] print_address_description.constprop.0 (mm/kasan/report.c:378) 
[ 40.026095][ T11] ? kobject_put (lib/kobject.c:729) 
[ 40.026331][ T11] print_report (mm/kasan/report.c:489) 
[ 40.026572][ T11] ? kasan_addr_to_slab (./arch/x86/include/asm/bitops.h:206 ./arch/x86/include/asm/bitops.h:238 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 ./include/linux/page-flags.h:481 mm/kasan/../slab.h:206 mm/kasan/common.c:38) 
[ 40.026839][ T11] kasan_report (mm/kasan/report.c:603) 
[ 40.027070][ T11] ? kobject_put (lib/kobject.c:729) 
[ 40.027308][ T11] kobject_put (lib/kobject.c:729) 
[ 40.027537][ T11] br_sysfs_delbr (net/bridge/br_sysfs_br.c:1086) 
[ 40.027775][ T11] br_dev_delete (net/bridge/br_if.c:396) 
[ 40.028021][ T11] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[ 40.028308][ T11] cleanup_net (net/core/net_namespace.c:628 (discriminator 2)) 
[ 40.028545][ T11] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5719) 
[ 40.028847][ T11] ? __pfx_cleanup_net (net/core/net_namespace.c:581) 
[ 40.029110][ T11] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5725) 
[ 40.029360][ T11] ? process_one_work (kernel/workqueue.c:2609) 
[ 40.029636][ T11] process_one_work (kernel/workqueue.c:2638) 
[ 40.029898][ T11] ? hlock_class (./arch/x86/include/asm/bitops.h:227 ./arch/x86/include/asm/bitops.h:239 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 kernel/locking/lockdep.c:228) 
[ 40.030143][ T11] ? __pfx_process_one_work (kernel/workqueue.c:2542) 
[ 40.030431][ T11] ? assign_work (kernel/workqueue.c:1101) 
[ 40.030684][ T11] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[ 40.030936][ T11] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[ 40.031207][ T11] kthread (kernel/kthread.c:388) 
[ 40.031428][ T11] ? __pfx_kthread (kernel/kthread.c:341) 
[ 40.031675][ T11] ret_from_fork (arch/x86/kernel/process.c:153) 
[ 40.031916][ T11] ? __pfx_kthread (kernel/kthread.c:341) 
[ 40.032172][ T11] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   40.051077][   T11] ------------[ cut here ]------------
| [   40.051371][   T11] refcount_t: underflow; use-after-free.
| [ 40.051719][ T11] WARNING: CPU: 0 PID: 11 at lib/refcount.c:28 refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) 
| [   40.052300][   T11] Modules linked in:
[   40.053083][   T11] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   40.053789][   T11] Workqueue: netns cleanup_net
[ 40.054055][ T11] RIP: 0010:refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) 
[ 40.054421][ T11] Code: f9 82 03 80 fb 01 0f 87 ee 02 b1 01 83 e3 01 0f 85 4d ff ff ff c6 05 9a f9 82 03 01 90 48 c7 c7 20 7a 62 9e e8 3e 05 2a ff 90 <0f> 0b 90 90 e9 2f ff ff ff 48 89 df e8 8c 68 a6 ff e9 b6 fe ff ff
All code
========
   0:	f9                   	stc
   1:	82                   	(bad)
   2:	03 80 fb 01 0f 87    	add    -0x78f0fe05(%rax),%eax
   8:	ee                   	out    %al,(%dx)
   9:	02 b1 01 83 e3 01    	add    0x1e38301(%rcx),%dh
   f:	0f 85 4d ff ff ff    	jne    0xffffffffffffff62
  15:	c6 05 9a f9 82 03 01 	movb   $0x1,0x382f99a(%rip)        # 0x382f9b6
  1c:	90                   	nop
  1d:	48 c7 c7 20 7a 62 9e 	mov    $0xffffffff9e627a20,%rdi
  24:	e8 3e 05 2a ff       	call   0xffffffffff2a0567
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	e9 2f ff ff ff       	jmp    0xffffffffffffff62
  33:	48 89 df             	mov    %rbx,%rdi
  36:	e8 8c 68 a6 ff       	call   0xffffffffffa668c7
  3b:	e9 b6 fe ff ff       	jmp    0xfffffffffffffef6

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	e9 2f ff ff ff       	jmp    0xffffffffffffff38
   9:	48 89 df             	mov    %rbx,%rdi
   c:	e8 8c 68 a6 ff       	call   0xffffffffffa6689d
  11:	e9 b6 fe ff ff       	jmp    0xfffffffffffffecc
[   40.055481][   T11] RSP: 0018:ffffc900000bfb98 EFLAGS: 00010282
[   40.055866][   T11] RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff9b91056f
[   40.056313][   T11] RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000001
[   40.056771][   T11] RBP: 0000000000000003 R08: 0000000000000000 R09: fffff52000017f18
[   40.057237][   T11] R10: ffffc900000bf8c7 R11: 205d313154202020 R12: ffff8880087d2000
[   40.057692][   T11] R13: ffff8880087d2df8 R14: ffffc900000bfc98 R15: ffff8880087d2bc0
[   40.058139][   T11] FS:  0000000000000000(0000) GS:ffff888035200000(0000) knlGS:0000000000000000
[   40.058642][   T11] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   40.059041][   T11] CR2: 0000000001ca7528 CR3: 0000000016534002 CR4: 00000000001706f0
[   40.059499][   T11] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   40.059947][   T11] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   40.060394][   T11] Call Trace:
[   40.060591][   T11]  <TASK>
[ 40.060770][ T11] ? __warn (kernel/panic.c:677) 
[ 40.060995][ T11] ? refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) 
[ 40.061289][ T11] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[ 40.061532][ T11] ? vprintk_emit (kernel/printk/printk.c:2313) 
[ 40.061781][ T11] ? handle_bug (arch/x86/kernel/traps.c:238) 
[ 40.062026][ T11] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[ 40.062277][ T11] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[ 40.062548][ T11] ? desc_read (./arch/x86/include/asm/atomic64_64.h:20 ./include/linux/atomic/atomic-arch-fallback.h:2615 ./include/linux/atomic/atomic-long.h:79 ./include/linux/atomic/atomic-instrumented.h:3196 kernel/printk/printk_ringbuffer.c:534) 
[ 40.062824][ T11] ? refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) 
[ 40.063150][ T11] ? refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) 
[ 40.063481][ T11] br_sysfs_delbr (net/bridge/br_sysfs_br.c:1086) 
[ 40.063740][ T11] br_dev_delete (net/bridge/br_if.c:396) 
[ 40.064018][ T11] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[ 40.064335][ T11] cleanup_net (net/core/net_namespace.c:628 (discriminator 2)) 
[ 40.064597][ T11] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5719) 
[ 40.064956][ T11] ? __pfx_cleanup_net (net/core/net_namespace.c:581) 
[ 40.065240][ T11] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5725) 
[ 40.065510][ T11] ? process_one_work (kernel/workqueue.c:2609) 
[ 40.065817][ T11] process_one_work (kernel/workqueue.c:2638) 
[ 40.066112][ T11] ? hlock_class (./arch/x86/include/asm/bitops.h:227 ./arch/x86/include/asm/bitops.h:239 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 kernel/locking/lockdep.c:228) 
[ 40.066386][ T11] ? __pfx_process_one_work (kernel/workqueue.c:2542) 
[ 40.066711][ T11] ? assign_work (kernel/workqueue.c:1101) 
[ 40.066994][ T11] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[ 40.067267][ T11] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[ 40.067568][ T11] kthread (kernel/kthread.c:388) 
[ 40.067800][ T11] ? __pfx_kthread (kernel/kthread.c:341) 
[ 40.068082][ T11] ret_from_fork (arch/x86/kernel/process.c:153) 
[ 40.068357][ T11] ? __pfx_kthread (kernel/kthread.c:341) 
[ 40.068620][ T11] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   40.071796][   T11] ------------[ cut here ]------------
| [   40.072138][   T11] sysfs group 'bridge' not found for kobject 'br0'
| [ 40.072536][ T11] WARNING: CPU: 0 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [   40.073133][   T11] Modules linked in:
[   40.073883][   T11] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   40.074559][   T11] Workqueue: netns cleanup_net
[ 40.074863][ T11] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 40.075211][ T11] Code: 89 d9 49 8b 14 24 48 b8 00 00 00 00 00 fc ff df 48 c1 e9 03 80 3c 01 00 75 45 48 8b 33 48 c7 c7 a0 a7 5c 9e e8 60 65 5e ff 90 <0f> 0b 90 90 48 83 c4 08 5b 5d 41 5c c3 cc cc cc cc e8 e9 c7 da ff
All code
========
   0:	89 d9                	mov    %ebx,%ecx
   2:	49 8b 14 24          	mov    (%r12),%rdx
   6:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
   d:	fc ff df 
  10:	48 c1 e9 03          	shr    $0x3,%rcx
  14:	80 3c 01 00          	cmpb   $0x0,(%rcx,%rax,1)
  18:	75 45                	jne    0x5f
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 a0 a7 5c 9e 	mov    $0xffffffff9e5ca7a0,%rdi
  24:	e8 60 65 5e ff       	call   0xffffffffff5e6589
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	48 83 c4 08          	add    $0x8,%rsp
  32:	5b                   	pop    %rbx
  33:	5d                   	pop    %rbp
  34:	41 5c                	pop    %r12
  36:	c3                   	ret
  37:	cc                   	int3
  38:	cc                   	int3
  39:	cc                   	int3
  3a:	cc                   	int3
  3b:	e8 e9 c7 da ff       	call   0xffffffffffdac829

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	48 83 c4 08          	add    $0x8,%rsp
   8:	5b                   	pop    %rbx
   9:	5d                   	pop    %rbp
   a:	41 5c                	pop    %r12
   c:	c3                   	ret
   d:	cc                   	int3
   e:	cc                   	int3
   f:	cc                   	int3
  10:	cc                   	int3
  11:	e8 e9 c7 da ff       	call   0xffffffffffdac7ff
[   40.076244][   T11] RSP: 0018:ffffc900000bfba0 EFLAGS: 00010282
[   40.076604][   T11] RAX: 0000000000000000 RBX: ffffffff9e9be220 RCX: ffffffff9b91056f
[   40.077069][   T11] RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000001
[   40.077521][   T11] RBP: 0000000000000000 R08: 0000000000000000 R09: fffff52000017f19
[   40.077967][   T11] R10: ffffc900000bf8cf R11: 205d313154202020 R12: ffff8880087d2628
[   40.078420][   T11] R13: ffff8880087d2df8 R14: ffffc900000bfc98 R15: ffff8880087d2bc0
[   40.078886][   T11] FS:  0000000000000000(0000) GS:ffff888035200000(0000) knlGS:0000000000000000
[   40.079393][   T11] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   40.079744][   T11] CR2: 0000000001ca7528 CR3: 0000000016534002 CR4: 00000000001706f0
[   40.080168][   T11] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   40.080588][   T11] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   40.081012][   T11] Call Trace:
[   40.081195][   T11]  <TASK>
[ 40.081354][ T11] ? __warn (kernel/panic.c:677) 
[ 40.081572][ T11] ? console_trylock (kernel/printk/printk.c:2659 kernel/printk/printk.c:2654) 
[ 40.081824][ T11] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 40.082141][ T11] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[ 40.082420][ T11] ? handle_bug (arch/x86/kernel/traps.c:238) 
[ 40.082689][ T11] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[ 40.082974][ T11] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[ 40.083267][ T11] ? desc_read (./arch/x86/include/asm/atomic64_64.h:20 ./include/linux/atomic/atomic-arch-fallback.h:2615 ./include/linux/atomic/atomic-long.h:79 ./include/linux/atomic/atomic-instrumented.h:3196 kernel/printk/printk_ringbuffer.c:534) 
[ 40.083517][ T11] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 40.083814][ T11] br_dev_delete (net/bridge/br_if.c:396) 
[ 40.084093][ T11] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[ 40.084393][ T11] cleanup_net (net/core/net_namespace.c:628 (discriminator 2)) 
[ 40.084665][ T11] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5719) 
[ 40.084989][ T11] ? __pfx_cleanup_net (net/core/net_namespace.c:581) 
[ 40.085299][ T11] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5725) 
[ 40.085596][ T11] ? process_one_work (kernel/workqueue.c:2609) 
[ 40.085913][ T11] process_one_work (kernel/workqueue.c:2638) 
[ 40.086203][ T11] ? hlock_class (./arch/x86/include/asm/bitops.h:227 ./arch/x86/include/asm/bitops.h:239 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 kernel/locking/lockdep.c:228) 
[ 40.086486][ T11] ? __pfx_process_one_work (kernel/workqueue.c:2542) 
[ 40.086806][ T11] ? assign_work (kernel/workqueue.c:1101) 
[ 40.087091][ T11] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[ 40.087365][ T11] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[ 40.087675][ T11] kthread (kernel/kthread.c:388) 
[ 40.087932][ T11] ? __pfx_kthread (kernel/kthread.c:341) 
[ 40.088213][ T11] ret_from_fork (arch/x86/kernel/process.c:153) 
[ 40.088479][ T11] ? __pfx_kthread (kernel/kthread.c:341) 
[ 40.088731][ T11] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   61.355644][   T11] ------------[ cut here ]------------
| [   61.356034][   T11] sysfs group 'bridge' not found for kobject 'br0'
| [ 61.356415][ T11] WARNING: CPU: 0 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [   61.356952][   T11] Modules linked in:
[   61.357667][   T11] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   61.358448][   T11] Workqueue: netns cleanup_net
[ 61.358744][ T11] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 61.359092][ T11] Code: 89 d9 49 8b 14 24 48 b8 00 00 00 00 00 fc ff df 48 c1 e9 03 80 3c 01 00 75 45 48 8b 33 48 c7 c7 a0 a7 5c 9e e8 60 65 5e ff 90 <0f> 0b 90 90 48 83 c4 08 5b 5d 41 5c c3 cc cc cc cc e8 e9 c7 da ff
All code
========
   0:	89 d9                	mov    %ebx,%ecx
   2:	49 8b 14 24          	mov    (%r12),%rdx
   6:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
   d:	fc ff df 
  10:	48 c1 e9 03          	shr    $0x3,%rcx
  14:	80 3c 01 00          	cmpb   $0x0,(%rcx,%rax,1)
  18:	75 45                	jne    0x5f
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 a0 a7 5c 9e 	mov    $0xffffffff9e5ca7a0,%rdi
  24:	e8 60 65 5e ff       	call   0xffffffffff5e6589
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	48 83 c4 08          	add    $0x8,%rsp
  32:	5b                   	pop    %rbx
  33:	5d                   	pop    %rbp
  34:	41 5c                	pop    %r12
  36:	c3                   	ret
  37:	cc                   	int3
  38:	cc                   	int3
  39:	cc                   	int3
  3a:	cc                   	int3
  3b:	e8 e9 c7 da ff       	call   0xffffffffffdac829

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	48 83 c4 08          	add    $0x8,%rsp
   8:	5b                   	pop    %rbx
   9:	5d                   	pop    %rbp
   a:	41 5c                	pop    %r12
   c:	c3                   	ret
   d:	cc                   	int3
   e:	cc                   	int3
   f:	cc                   	int3
  10:	cc                   	int3
  11:	e8 e9 c7 da ff       	call   0xffffffffffdac7ff
[   61.360168][   T11] RSP: 0018:ffffc900000bfba0 EFLAGS: 00010282
[   61.360540][   T11] RAX: 0000000000000000 RBX: ffffffff9e9be220 RCX: ffffffff9b91056f
[   61.361002][   T11] RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000001
[   61.361443][   T11] RBP: 0000000000000000 R08: 0000000000000000 R09: fffff52000017f19
[   61.361892][   T11] R10: ffffc900000bf8cf R11: 205d313154202020 R12: ffff888017e0a628
[   61.362326][   T11] R13: ffff888017e0adf8 R14: ffffc900000bfc98 R15: ffff888017e0abc0
[   61.362743][   T11] FS:  0000000000000000(0000) GS:ffff888035200000(0000) knlGS:0000000000000000
[   61.363216][   T11] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   61.363574][   T11] CR2: 00007fd6401b8000 CR3: 0000000016534006 CR4: 00000000001706f0
[   61.364088][   T11] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   61.364538][   T11] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   61.364987][   T11] Call Trace:
[   61.365180][   T11]  <TASK>
[ 61.365367][ T11] ? __warn (kernel/panic.c:677) 
[ 61.365627][ T11] ? console_trylock (kernel/printk/printk.c:2659 kernel/printk/printk.c:2654) 
[ 61.365913][ T11] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 61.366220][ T11] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[ 61.366504][ T11] ? handle_bug (arch/x86/kernel/traps.c:238) 
[ 61.366767][ T11] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[ 61.367052][ T11] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[ 61.367361][ T11] ? desc_read (./arch/x86/include/asm/atomic64_64.h:20 ./include/linux/atomic/atomic-arch-fallback.h:2615 ./include/linux/atomic/atomic-long.h:79 ./include/linux/atomic/atomic-instrumented.h:3196 kernel/printk/printk_ringbuffer.c:534) 
[ 61.367634][ T11] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 61.367957][ T11] br_dev_delete (net/bridge/br_if.c:396) 
[ 61.368238][ T11] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[ 61.368563][ T11] cleanup_net (net/core/net_namespace.c:628 (discriminator 2)) 
[ 61.368829][ T11] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5725) 
[ 61.369088][ T11] ? __pfx_cleanup_net (net/core/net_namespace.c:581) 
[ 61.369352][ T11] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5725) 
[ 61.369606][ T11] ? process_one_work (kernel/workqueue.c:2609) 
[ 61.369881][ T11] process_one_work (kernel/workqueue.c:2638) 
[ 61.370152][ T11] ? hlock_class (./arch/x86/include/asm/bitops.h:227 ./arch/x86/include/asm/bitops.h:239 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 kernel/locking/lockdep.c:228) 
[ 61.370397][ T11] ? __pfx_process_one_work (kernel/workqueue.c:2542) 
[ 61.370685][ T11] ? assign_work (kernel/workqueue.c:1101) 
[ 61.370970][ T11] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[ 61.371266][ T11] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[ 61.371565][ T11] kthread (kernel/kthread.c:388) 
[ 61.371819][ T11] ? __pfx_kthread (kernel/kthread.c:341) 
[ 61.372074][ T11] ret_from_fork (arch/x86/kernel/process.c:153) 
[ 61.372313][ T11] ? __pfx_kthread (kernel/kthread.c:341) 
[ 61.372561][ T11] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [   82.292959][   T11] ------------[ cut here ]------------
| [   82.293311][   T11] sysfs group 'bridge' not found for kobject 'br0'
| [ 82.293742][ T11] WARNING: CPU: 1 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [   82.294286][   T11] Modules linked in:
[   82.295108][   T11] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   82.295853][   T11] Workqueue: netns cleanup_net
[ 82.296119][ T11] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 82.296433][ T11] Code: 89 d9 49 8b 14 24 48 b8 00 00 00 00 00 fc ff df 48 c1 e9 03 80 3c 01 00 75 45 48 8b 33 48 c7 c7 a0 a7 5c 9e e8 60 65 5e ff 90 <0f> 0b 90 90 48 83 c4 08 5b 5d 41 5c c3 cc cc cc cc e8 e9 c7 da ff
All code
========
   0:	89 d9                	mov    %ebx,%ecx
   2:	49 8b 14 24          	mov    (%r12),%rdx
   6:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
   d:	fc ff df 
  10:	48 c1 e9 03          	shr    $0x3,%rcx
  14:	80 3c 01 00          	cmpb   $0x0,(%rcx,%rax,1)
  18:	75 45                	jne    0x5f
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 a0 a7 5c 9e 	mov    $0xffffffff9e5ca7a0,%rdi
  24:	e8 60 65 5e ff       	call   0xffffffffff5e6589
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	48 83 c4 08          	add    $0x8,%rsp
  32:	5b                   	pop    %rbx
  33:	5d                   	pop    %rbp
  34:	41 5c                	pop    %r12
  36:	c3                   	ret
  37:	cc                   	int3
  38:	cc                   	int3
  39:	cc                   	int3
  3a:	cc                   	int3
  3b:	e8 e9 c7 da ff       	call   0xffffffffffdac829

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	48 83 c4 08          	add    $0x8,%rsp
   8:	5b                   	pop    %rbx
   9:	5d                   	pop    %rbp
   a:	41 5c                	pop    %r12
   c:	c3                   	ret
   d:	cc                   	int3
   e:	cc                   	int3
   f:	cc                   	int3
  10:	cc                   	int3
  11:	e8 e9 c7 da ff       	call   0xffffffffffdac7ff
[   82.297544][   T11] RSP: 0018:ffffc900000bfba0 EFLAGS: 00010282
[   82.297886][   T11] RAX: 0000000000000000 RBX: ffffffff9e9be220 RCX: ffffffff9b91056f
[   82.298370][   T11] RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000001
[   82.298827][   T11] RBP: 0000000000000000 R08: 0000000000000000 R09: fffff52000017f19
[   82.299308][   T11] R10: ffffc900000bf8cf R11: 205d313154202020 R12: ffff8880069b2628
[   82.299777][   T11] R13: ffff8880069b2df8 R14: ffffc900000bfc98 R15: ffff8880069b2bc0
[   82.300245][   T11] FS:  0000000000000000(0000) GS:ffff888035600000(0000) knlGS:0000000000000000
[   82.300771][   T11] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   82.301137][   T11] CR2: 00007f126f989000 CR3: 0000000016534005 CR4: 00000000001706f0
[   82.301554][   T11] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   82.301984][   T11] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   82.302399][   T11] Call Trace:
[   82.302573][   T11]  <TASK>
[ 82.302738][ T11] ? __warn (kernel/panic.c:677) 
[ 82.302988][ T11] ? console_trylock (kernel/printk/printk.c:2659 kernel/printk/printk.c:2654) 
[ 82.303271][ T11] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 82.303576][ T11] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[ 82.303840][ T11] ? handle_bug (arch/x86/kernel/traps.c:238) 
[ 82.304110][ T11] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[ 82.304392][ T11] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[ 82.304693][ T11] ? desc_read (./arch/x86/include/asm/atomic64_64.h:20 ./include/linux/atomic/atomic-arch-fallback.h:2615 ./include/linux/atomic/atomic-long.h:79 ./include/linux/atomic/atomic-instrumented.h:3196 kernel/printk/printk_ringbuffer.c:534) 
[ 82.304959][ T11] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 82.305257][ T11] br_dev_delete (net/bridge/br_if.c:396) 
[ 82.305552][ T11] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[ 82.305850][ T11] cleanup_net (net/core/net_namespace.c:628 (discriminator 2)) 
[ 82.306124][ T11] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5725) 
[ 82.306402][ T11] ? __pfx_cleanup_net (net/core/net_namespace.c:581) 
[ 82.306684][ T11] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5725) 
[ 82.306952][ T11] ? process_one_work (kernel/workqueue.c:2609) 
[ 82.307266][ T11] process_one_work (kernel/workqueue.c:2638) 
[ 82.307540][ T11] ? hlock_class (./arch/x86/include/asm/bitops.h:227 ./arch/x86/include/asm/bitops.h:239 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 kernel/locking/lockdep.c:228) 
[ 82.307803][ T11] ? __pfx_process_one_work (kernel/workqueue.c:2542) 
[ 82.308135][ T11] ? assign_work (kernel/workqueue.c:1101) 
[ 82.308400][ T11] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[ 82.308677][ T11] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[ 82.308970][ T11] kthread (kernel/kthread.c:388) 
[ 82.309188][ T11] ? __pfx_kthread (kernel/kthread.c:341) 
[ 82.309430][ T11] ret_from_fork (arch/x86/kernel/process.c:153) 
[ 82.309670][ T11] ? __pfx_kthread (kernel/kthread.c:341) 
[ 82.309913][ T11] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [  104.035301][   T11] ------------[ cut here ]------------
| [  104.035634][   T11] sysfs group 'bridge' not found for kobject 'br0'
| [ 104.036049][ T11] WARNING: CPU: 2 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
| [  104.036563][   T11] Modules linked in:
[  104.037505][   T11] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[  104.038212][   T11] Workqueue: netns cleanup_net
[ 104.038469][ T11] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 104.038779][ T11] Code: 89 d9 49 8b 14 24 48 b8 00 00 00 00 00 fc ff df 48 c1 e9 03 80 3c 01 00 75 45 48 8b 33 48 c7 c7 a0 a7 5c 9e e8 60 65 5e ff 90 <0f> 0b 90 90 48 83 c4 08 5b 5d 41 5c c3 cc cc cc cc e8 e9 c7 da ff
All code
========
   0:	89 d9                	mov    %ebx,%ecx
   2:	49 8b 14 24          	mov    (%r12),%rdx
   6:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
   d:	fc ff df 
  10:	48 c1 e9 03          	shr    $0x3,%rcx
  14:	80 3c 01 00          	cmpb   $0x0,(%rcx,%rax,1)
  18:	75 45                	jne    0x5f
  1a:	48 8b 33             	mov    (%rbx),%rsi
  1d:	48 c7 c7 a0 a7 5c 9e 	mov    $0xffffffff9e5ca7a0,%rdi
  24:	e8 60 65 5e ff       	call   0xffffffffff5e6589
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	48 83 c4 08          	add    $0x8,%rsp
  32:	5b                   	pop    %rbx
  33:	5d                   	pop    %rbp
  34:	41 5c                	pop    %r12
  36:	c3                   	ret
  37:	cc                   	int3
  38:	cc                   	int3
  39:	cc                   	int3
  3a:	cc                   	int3
  3b:	e8 e9 c7 da ff       	call   0xffffffffffdac829

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	48 83 c4 08          	add    $0x8,%rsp
   8:	5b                   	pop    %rbx
   9:	5d                   	pop    %rbp
   a:	41 5c                	pop    %r12
   c:	c3                   	ret
   d:	cc                   	int3
   e:	cc                   	int3
   f:	cc                   	int3
  10:	cc                   	int3
  11:	e8 e9 c7 da ff       	call   0xffffffffffdac7ff
[  104.039871][   T11] RSP: 0018:ffffc900000bfba0 EFLAGS: 00010282
[  104.040218][   T11] RAX: 0000000000000000 RBX: ffffffff9e9be220 RCX: ffffffff9b91056f
[  104.040675][   T11] RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000001
[  104.041148][   T11] RBP: 0000000000000000 R08: 0000000000000000 R09: fffff52000017f19
[  104.041602][   T11] R10: ffffc900000bf8cf R11: 205d313154202020 R12: ffff888006b12628
[  104.042071][   T11] R13: ffff888006b12df8 R14: ffffc900000bfc98 R15: ffff888006b12bc0
[  104.042529][   T11] FS:  0000000000000000(0000) GS:ffff888035a00000(0000) knlGS:0000000000000000
[  104.043054][   T11] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  104.043429][   T11] CR2: 00007f6d8270d270 CR3: 0000000006470003 CR4: 00000000001706f0
[  104.043875][   T11] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  104.044329][   T11] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  104.044767][   T11] Call Trace:
[  104.044963][   T11]  <TASK>
[ 104.045131][ T11] ? __warn (kernel/panic.c:677) 
[ 104.045373][ T11] ? console_trylock (kernel/printk/printk.c:2659 kernel/printk/printk.c:2654) 
[ 104.045643][ T11] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 104.045963][ T11] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[ 104.046207][ T11] ? handle_bug (arch/x86/kernel/traps.c:238) 
[ 104.046442][ T11] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) 
[ 104.046688][ T11] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[ 104.046965][ T11] ? desc_read (./arch/x86/include/asm/atomic64_64.h:20 ./include/linux/atomic/atomic-arch-fallback.h:2615 ./include/linux/atomic/atomic-long.h:79 ./include/linux/atomic/atomic-instrumented.h:3196 kernel/printk/printk_ringbuffer.c:534) 
[ 104.047206][ T11] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) 
[ 104.047482][ T11] br_dev_delete (net/bridge/br_if.c:396) 
[ 104.047736][ T11] br_net_exit_batch_rtnl (net/bridge/br.c:369) 
[ 104.048028][ T11] cleanup_net (net/core/net_namespace.c:628 (discriminator 2)) 
[ 104.048297][ T11] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5725) 
[ 104.048570][ T11] ? __pfx_cleanup_net (net/core/net_namespace.c:581) 
[ 104.048862][ T11] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5725) 
[ 104.049161][ T11] ? process_one_work (kernel/workqueue.c:2609) 
[ 104.049454][ T11] process_one_work (kernel/workqueue.c:2638) 
[ 104.049749][ T11] ? hlock_class (./arch/x86/include/asm/bitops.h:227 ./arch/x86/include/asm/bitops.h:239 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 kernel/locking/lockdep.c:228) 
[ 104.050014][ T11] ? __pfx_process_one_work (kernel/workqueue.c:2542) 
[ 104.050296][ T11] ? assign_work (kernel/workqueue.c:1101) 
[ 104.050539][ T11] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[ 104.050796][ T11] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[ 104.051076][ T11] kthread (kernel/kthread.c:388) 
[ 104.051296][ T11] ? __pfx_kthread (kernel/kthread.c:341) 
[ 104.051540][ T11] ret_from_fork (arch/x86/kernel/process.c:153) 
[ 104.051785][ T11] ? __pfx_kthread (kernel/kthread.c:341) 


Finger prints:
dump_stack_lvl:print_report:kasan_report:kobject_put
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