======================================
| [   16.948355][  T253] ==================================================================
| [   16.948704][  T253] BUG: KASAN: null-ptr-deref in try_to_grab_pending (./arch/x86/include/asm/bitops.h:136 ./include/asm-generic/bitops/instrumented-atomic.h:72 kernel/workqueue.c:2072)
| [   16.949014][  T253] Write of size 8 at addr 0000000000000000 by task tfo_passive.sh/253
| [   16.949316][  T253]
[   16.949424][  T253] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   16.949426][  T253] Call Trace:
[   16.949428][  T253]  <TASK>
[   16.949430][  T253]  dump_stack_lvl (lib/dump_stack.c:123)
[   16.949437][  T253]  ? try_to_grab_pending (./arch/x86/include/asm/bitops.h:136 ./include/asm-generic/bitops/instrumented-atomic.h:72 kernel/workqueue.c:2072)
[   16.949440][  T253]  kasan_report (mm/kasan/report.c:597)
[   16.949446][  T253]  ? try_to_grab_pending (./arch/x86/include/asm/bitops.h:136 ./include/asm-generic/bitops/instrumented-atomic.h:72 kernel/workqueue.c:2072)
[   16.949452][  T253]  kasan_check_range (mm/kasan/generic.c:194 mm/kasan/generic.c:200)
[   16.949456][  T253]  try_to_grab_pending (./arch/x86/include/asm/bitops.h:136 ./include/asm-generic/bitops/instrumented-atomic.h:72 kernel/workqueue.c:2072)
[   16.949459][  T253]  ? page_pool_release (net/core/page_pool.c:1196)
[   16.949465][  T253]  __cancel_work (kernel/workqueue.c:2161 kernel/workqueue.c:4364)
[   16.949469][  T253]  ? enable_delayed_work (kernel/workqueue.c:4359)
[   16.949472][  T253]  ? page_pool_release (net/core/page_pool.c:1196)
[   16.949476][  T253]  ? page_pool_destroy (net/core/page_pool.c:1296)
[   16.949481][  T253]  __cancel_work_sync (kernel/workqueue.c:4383)
[   16.949485][  T253]  __dev_close_many (net/core/dev.c:1879 (discriminator 2) net/core/dev.c:1932 (discriminator 2))
[   16.949490][  T253]  ? netdev_notify_peers (net/core/dev.c:1891)
[   16.949494][  T253]  ? __mutex_lock (./arch/x86/include/asm/preempt.h:104 kernel/locking/mutex.c:739 kernel/locking/mutex.c:760)
[   16.949502][  T253]  netif_close_many (net/core/dev.c:1959)
[   16.949505][  T253]  ? ww_mutex_lock (kernel/locking/mutex.c:759)
[   16.949509][  T253]  ? __dev_close_many (net/core/dev.c:1949)
[   16.949511][  T253]  ? validate_chain (kernel/locking/lockdep.c:3801 kernel/locking/lockdep.c:3821 kernel/locking/lockdep.c:3876)
[   16.949516][  T253]  ? find_held_lock (kernel/locking/lockdep.c:5350)
[   16.949522][  T253]  netif_close_many_and_unlock (net/core/dev.c:12476)
[   16.949527][  T253]  unregister_netdevice_many_notify (net/core/dev.c:12539)
[   16.949530][  T253]  ? __mutex_handoff (kernel/locking/mutex.c:88)
[   16.949533][  T253]  ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:751)
[   16.949540][  T253]  ? dev_ingress_queue_create (net/core/dev.c:12499)
[   16.949543][  T253]  ? __mutex_lock (./arch/x86/include/asm/preempt.h:104 kernel/locking/mutex.c:739 kernel/locking/mutex.c:760)
[   16.949546][  T253]  ? __rtnl_unlock (net/core/rtnetlink.c:145 (discriminator 3))
[   16.949550][  T253]  ? nsim_destroy (drivers/net/netdevsim/netdev.c:1174) netdevsim
[   16.949564][  T253]  ? ww_mutex_lock (kernel/locking/mutex.c:759)
[   16.949569][  T253]  unregister_netdevice_queue (net/core/dev.c:12452)
[   16.949573][  T253]  ? unregister_netdevice_many (net/core/dev.c:12441)
[   16.949579][  T253] nsim_destroy (drivers/net/netdevsim/netdev.c:1179 (discriminator 2)) netdevsim
[   16.949596][  T253] __nsim_dev_port_del (drivers/net/netdevsim/dev.c:443 drivers/net/netdevsim/dev.c:1528) netdevsim
[   16.949611][  T253] nsim_dev_reload_destroy (drivers/net/netdevsim/dev.c:1537 drivers/net/netdevsim/dev.c:1762) netdevsim
[   16.949623][  T253] nsim_drv_remove (drivers/net/netdevsim/dev.c:1779) netdevsim
[   16.949634][  T253]  device_release_driver_internal (drivers/base/dd.c:1276 drivers/base/dd.c:1297)
[   16.949640][  T253]  ? klist_put (lib/klist.c:220)
[   16.949644][  T253]  bus_remove_device (./include/linux/kobject.h:193 drivers/base/base.h:73 drivers/base/bus.c:586)
[   16.949649][  T253]  device_del (drivers/base/core.c:3879)
[   16.949653][  T253]  ? __device_link_del (drivers/base/core.c:3833)
[   16.949659][  T253]  device_unregister (drivers/base/core.c:3796 drivers/base/core.c:3920)
[   16.949662][  T253] del_device_store (drivers/net/netdevsim/bus.c:248) netdevsim
[   16.949674][  T253]  ? nsim_bus_dev_numvfs_show (drivers/net/netdevsim/bus.c:215) netdevsim
[   16.949683][  T253]  ? sysfs_file_kobj (./include/linux/rcupdate.h:341 ./include/linux/rcupdate.h:897 ./include/linux/rcupdate.h:1195 fs/sysfs/file.c:24)
[   16.949688][  T253]  ? sysfs_file_kobj (fs/sysfs/file.c:26)
[   16.949692][  T253]  ? sysfs_file_ops (fs/sysfs/file.c:135)
[   16.949694][  T253]  kernfs_fop_write_iter (fs/kernfs/file.c:88 fs/kernfs/file.c:356)
[   16.949698][  T253]  vfs_write (fs/read_write.c:594 fs/read_write.c:686)
[   16.949704][  T253]  ? kernel_write (fs/read_write.c:667)
[   16.949709][  T253]  ? __lock_acquire (kernel/locking/lockdep.c:5237)
[   16.949715][  T253]  ksys_write (fs/read_write.c:738)
[   16.949719][  T253]  ? __ia32_sys_read (fs/read_write.c:728)
[   16.949725][  T253]  do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94)
[   16.949729][  T253]  entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[   16.949733][  T253] RIP: 0033:0x7f021fd6e257
[   16.949736][  T253] Code: 0f 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24
All code
========
   0:	0f 00                	(bad)
   2:	f7 d8                	neg    %eax
   4:	64 89 02             	mov    %eax,%fs:(%rdx)
   7:	48 c7 c0 ff ff ff ff 	mov    $0xffffffffffffffff,%rax
   e:	eb b7                	jmp    0xffffffffffffffc7
  10:	0f 1f 00             	nopl   (%rax)
  13:	f3 0f 1e fa          	endbr64
  17:	64 8b 04 25 18 00 00 	mov    %fs:0x18,%eax
  1e:	00 
  1f:	85 c0                	test   %eax,%eax
  21:	75 10                	jne    0x33
  23:	b8 01 00 00 00       	mov    $0x1,%eax
  28:	0f 05                	syscall
  2a:*	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax		<-- trapping instruction
  30:	77 51                	ja     0x83
  32:	c3                   	ret
  33:	48 83 ec 28          	sub    $0x28,%rsp
  37:	48 89 54 24 18       	mov    %rdx,0x18(%rsp)
  3c:	48                   	rex.W
  3d:	89                   	.byte 0x89
  3e:	74 24                	je     0x64

Code starting with the faulting instruction
===========================================
   0:	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax
   6:	77 51                	ja     0x59
   8:	c3                   	ret
   9:	48 83 ec 28          	sub    $0x28,%rsp
   d:	48 89 54 24 18       	mov    %rdx,0x18(%rsp)
  12:	48                   	rex.W
  13:	89                   	.byte 0x89
  14:	74 24                	je     0x3a
[   16.949739][  T253] RSP: 002b:00007ffcfe74df68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[   16.949743][  T253] RAX: ffffffffffffffda RBX: 00007f021fe6a780 RCX: 00007f021fd6e257
[   16.949745][  T253] RDX: 0000000000000004 RSI: 00005645a43e7ac0 RDI: 0000000000000001
[   16.949747][  T253] RBP: 0000000000000004 R08: 0000000000000000 R09: 00007f021fe20d20
[   16.949748][  T253] R10: 00007f021fe20c20 R11: 0000000000000246 R12: 0000000000000004
[   16.949750][  T253] R13: 00005645a43e7ac0 R14: 0000000000000004 R15: 00007f021fe659c0
| [   16.965094][  T253] #PF: error_code(0x0002) - not-present page
| [   16.965331][  T253] PGD 0 P4D 0
| [   16.965479][  T253] Oops: Oops: 0002 [#1] SMP KASAN
| [   16.966125][  T253] Tainted: [B]=BAD_PAGE
[   16.966272][  T253] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   16.966515][  T253] RIP: 0010:try_to_grab_pending (./arch/x86/include/asm/bitops.h:136 ./include/asm-generic/bitops/instrumented-atomic.h:72 kernel/workqueue.c:2072)
[   16.966774][  T253] Code: 00 41 89 c0 b8 01 00 00 00 45 85 c0 74 0f 48 83 c4 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3 be 08 00 00 00 48 89 df e8 1f 93 82 00 <f0> 48 0f ba 2b 00 72 11 48 83 c4 10 31 c0 5b 5d 41 5c 41 5d 41 5e
All code
========
   0:	00 41 89             	add    %al,-0x77(%rcx)
   3:	c0 b8 01 00 00 00 45 	sarb   $0x45,0x1(%rax)
   a:	85 c0                	test   %eax,%eax
   c:	74 0f                	je     0x1d
   e:	48 83 c4 10          	add    $0x10,%rsp
  12:	5b                   	pop    %rbx
  13:	5d                   	pop    %rbp
  14:	41 5c                	pop    %r12
  16:	41 5d                	pop    %r13
  18:	41 5e                	pop    %r14
  1a:	41 5f                	pop    %r15
  1c:	c3                   	ret
  1d:	be 08 00 00 00       	mov    $0x8,%esi
  22:	48 89 df             	mov    %rbx,%rdi
  25:	e8 1f 93 82 00       	call   0x829349
  2a:*	f0 48 0f ba 2b 00    	lock btsq $0x0,(%rbx)		<-- trapping instruction
  30:	72 11                	jb     0x43
  32:	48 83 c4 10          	add    $0x10,%rsp
  36:	31 c0                	xor    %eax,%eax
  38:	5b                   	pop    %rbx
  39:	5d                   	pop    %rbp
  3a:	41 5c                	pop    %r12
  3c:	41 5d                	pop    %r13
  3e:	41 5e                	pop    %r14

Code starting with the faulting instruction
===========================================
   0:	f0 48 0f ba 2b 00    	lock btsq $0x0,(%rbx)
   6:	72 11                	jb     0x19
   8:	48 83 c4 10          	add    $0x10,%rsp
   c:	31 c0                	xor    %eax,%eax
   e:	5b                   	pop    %rbx
   f:	5d                   	pop    %rbp
  10:	41 5c                	pop    %r12
  12:	41 5d                	pop    %r13
  14:	41 5e                	pop    %r14
[   16.967450][  T253] RSP: 0018:ffffc90000ba7510 EFLAGS: 00010046
[   16.967706][  T253] RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff93249b8a
[   16.967993][  T253] RDX: fffffbfff2fecacd RSI: 0000000000000008 RDI: ffffffff97f65660
[   16.968279][  T253] RBP: ffffc90000ba7578 R08: 0000000000000001 R09: fffffbfff2fecacc
[   16.968563][  T253] R10: ffffffff97f65667 R11: ffffc90000ba7000 R12: 0000000000000000
[   16.968858][  T253] R13: 0000000000000282 R14: ffff888005a62000 R15: dffffc0000000000
[   16.969145][  T253] FS:  00007f021fc6e000(0000) GS:ffff8880d5187000(0000) knlGS:0000000000000000
[   16.969478][  T253] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   16.969726][  T253] CR2: 0000000000000000 CR3: 0000000004f07001 CR4: 0000000000772ef0
[   16.970016][  T253] PKRU: 55555554
[   16.970164][  T253] Call Trace:
[   16.970309][  T253]  <TASK>
[   16.970406][  T253]  ? page_pool_release (net/core/page_pool.c:1196)
[   16.970611][  T253]  __cancel_work (kernel/workqueue.c:2161 kernel/workqueue.c:4364)
[   16.970806][  T253]  ? enable_delayed_work (kernel/workqueue.c:4359)
[   16.970999][  T253]  ? page_pool_release (net/core/page_pool.c:1196)
[   16.971190][  T253]  ? page_pool_destroy (net/core/page_pool.c:1296)
[   16.971383][  T253]  __cancel_work_sync (kernel/workqueue.c:4383)
[   16.971579][  T253]  __dev_close_many (net/core/dev.c:1879 (discriminator 2) net/core/dev.c:1932 (discriminator 2))
[   16.971784][  T253]  ? netdev_notify_peers (net/core/dev.c:1891)
[   16.971977][  T253]  ? __mutex_lock (./arch/x86/include/asm/preempt.h:104 kernel/locking/mutex.c:739 kernel/locking/mutex.c:760)
[   16.972169][  T253]  netif_close_many (net/core/dev.c:1959)
[   16.972372][  T253]  ? ww_mutex_lock (kernel/locking/mutex.c:759)
[   16.972562][  T253]  ? __dev_close_many (net/core/dev.c:1949)
[   16.972759][  T253]  ? validate_chain (kernel/locking/lockdep.c:3801 kernel/locking/lockdep.c:3821 kernel/locking/lockdep.c:3876)
[   16.972950][  T253]  ? find_held_lock (kernel/locking/lockdep.c:5350)
[   16.973147][  T253]  netif_close_many_and_unlock (net/core/dev.c:12476)
[   16.973340][  T253]  unregister_netdevice_many_notify (net/core/dev.c:12539)
[   16.973578][  T253]  ? __mutex_handoff (kernel/locking/mutex.c:88)
[   16.973779][  T253]  ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:751)
[   16.973973][  T253]  ? dev_ingress_queue_create (net/core/dev.c:12499)
[   16.974162][  T253]  ? __mutex_lock (./arch/x86/include/asm/preempt.h:104 kernel/locking/mutex.c:739 kernel/locking/mutex.c:760)
[   16.974353][  T253]  ? __rtnl_unlock (net/core/rtnetlink.c:145 (discriminator 3))
[   16.974543][  T253]  ? nsim_destroy (drivers/net/netdevsim/netdev.c:1174) netdevsim
[   16.974754][  T253]  ? ww_mutex_lock (kernel/locking/mutex.c:759)
[   16.974947][  T253]  unregister_netdevice_queue (net/core/dev.c:12452)
[   16.975138][  T253]  ? unregister_netdevice_many (net/core/dev.c:12441)
[   16.975330][  T253] nsim_destroy (drivers/net/netdevsim/netdev.c:1179 (discriminator 2)) netdevsim
[   16.975531][  T253] __nsim_dev_port_del (drivers/net/netdevsim/dev.c:443 drivers/net/netdevsim/dev.c:1528) netdevsim
[   16.975784][  T253] nsim_dev_reload_destroy (drivers/net/netdevsim/dev.c:1537 drivers/net/netdevsim/dev.c:1762) netdevsim
[   16.976036][  T253] nsim_drv_remove (drivers/net/netdevsim/dev.c:1779) netdevsim
[   16.976234][  T253]  device_release_driver_internal (drivers/base/dd.c:1276 drivers/base/dd.c:1297)
[   16.976472][  T253]  ? klist_put (lib/klist.c:220)
[   16.976622][  T253]  bus_remove_device (./include/linux/kobject.h:193 drivers/base/base.h:73 drivers/base/bus.c:586)
[   16.976815][  T253]  device_del (drivers/base/core.c:3879)
[   16.976958][  T253]  ? __device_link_del (drivers/base/core.c:3833)
[   16.977151][  T253]  device_unregister (drivers/base/core.c:3796 drivers/base/core.c:3920)
[   16.977341][  T253] del_device_store (drivers/net/netdevsim/bus.c:248) netdevsim
[   16.977587][  T253]  ? nsim_bus_dev_numvfs_show (drivers/net/netdevsim/bus.c:215) netdevsim
[   16.977839][  T253]  ? sysfs_file_kobj (./include/linux/rcupdate.h:341 ./include/linux/rcupdate.h:897 ./include/linux/rcupdate.h:1195 fs/sysfs/file.c:24)
[   16.978029][  T253]  ? sysfs_file_kobj (fs/sysfs/file.c:26)
[   16.978219][  T253]  ? sysfs_file_ops (fs/sysfs/file.c:135)
[   16.978408][  T253]  kernfs_fop_write_iter (fs/kernfs/file.c:88 fs/kernfs/file.c:356)
[   16.978608][  T253]  vfs_write (fs/read_write.c:594 fs/read_write.c:686)
[   16.978760][  T253]  ? kernel_write (fs/read_write.c:667)
[   16.978954][  T253]  ? __lock_acquire (kernel/locking/lockdep.c:5237)
[   16.979146][  T253]  ksys_write (fs/read_write.c:738)
[   16.979289][  T253]  ? __ia32_sys_read (fs/read_write.c:728)
[   16.979481][  T253]  do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94)
[   16.979679][  T253]  entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[   16.979917][  T253] RIP: 0033:0x7f021fd6e257
[   16.980117][  T253] Code: 0f 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24
All code
========
   0:	0f 00                	(bad)
   2:	f7 d8                	neg    %eax
   4:	64 89 02             	mov    %eax,%fs:(%rdx)
   7:	48 c7 c0 ff ff ff ff 	mov    $0xffffffffffffffff,%rax
   e:	eb b7                	jmp    0xffffffffffffffc7
  10:	0f 1f 00             	nopl   (%rax)
  13:	f3 0f 1e fa          	endbr64
  17:	64 8b 04 25 18 00 00 	mov    %fs:0x18,%eax
  1e:	00 
  1f:	85 c0                	test   %eax,%eax
  21:	75 10                	jne    0x33
  23:	b8 01 00 00 00       	mov    $0x1,%eax
  28:	0f 05                	syscall
  2a:*	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax		<-- trapping instruction
  30:	77 51                	ja     0x83
  32:	c3                   	ret
  33:	48 83 ec 28          	sub    $0x28,%rsp
  37:	48 89 54 24 18       	mov    %rdx,0x18(%rsp)
  3c:	48                   	rex.W
  3d:	89                   	.byte 0x89
  3e:	74 24                	je     0x64

Code starting with the faulting instruction
===========================================
   0:	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax
   6:	77 51                	ja     0x59
   8:	c3                   	ret
   9:	48 83 ec 28          	sub    $0x28,%rsp
   d:	48 89 54 24 18       	mov    %rdx,0x18(%rsp)
  12:	48                   	rex.W
  13:	89                   	.byte 0x89
  14:	74 24                	je     0x3a
[   16.980805][  T253] RSP: 002b:00007ffcfe74df68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[   16.981094][  T253] RAX: ffffffffffffffda RBX: 00007f021fe6a780 RCX: 00007f021fd6e257
[   16.981381][  T253] RDX: 0000000000000004 RSI: 00005645a43e7ac0 RDI: 0000000000000001
[   16.981676][  T253] RBP: 0000000000000004 R08: 0000000000000000 R09: 00007f021fe20d20
[   16.981966][  T253] R10: 00007f021fe20c20 R11: 0000000000000246 R12: 0000000000000004


Finger prints:
kasan_report:kasan_check_range:try_to_grab_pending:__cancel_work:__cancel_work_sync
try_to_grab_pending:__cancel_work:__cancel_work_sync:__dev_close_many:netif_close_many