======================================
| 0
| xx__-> [   12.013698][  T218] ------------[ cut here ]------------
| [ 12.014080][ T218] WARNING: CPU: 3 PID: 218 at ./include/net/netdev_lock.h:52 __netdev_update_features (./include/net/netdev_lock.h:52 ./include/net/netdev_lock.h:49 net/core/dev.c:10566) 
| [   12.014544][  T218] Modules linked in: netdevsim
[   12.015108][  T218] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[ 12.015392][ T218] RIP: 0010:__netdev_update_features (./include/net/netdev_lock.h:52 ./include/net/netdev_lock.h:49 net/core/dev.c:10566) 
[ 12.015670][ T218] Code: 00 e8 a3 4a fe ff 48 8b 5c 24 58 e9 87 fb ff ff 49 8d bf 90 0c 00 00 be ff ff ff ff e8 08 e9 78 00 85 c0 0f 85 99 00 00 00 90 <0f> 0b 90 48 b8 00 00 00 00 00 fc ff df 48 8b 54 24 20 48 c1 ea 03
All code
========
   0:	00 e8                	add    %ch,%al
   2:	a3 4a fe ff 48 8b 5c 	movabs %eax,0x58245c8b48fffe4a
   9:	24 58 
   b:	e9 87 fb ff ff       	jmp    0xfffffffffffffb97
  10:	49 8d bf 90 0c 00 00 	lea    0xc90(%r15),%rdi
  17:	be ff ff ff ff       	mov    $0xffffffff,%esi
  1c:	e8 08 e9 78 00       	call   0x78e929
  21:	85 c0                	test   %eax,%eax
  23:	0f 85 99 00 00 00    	jne    0xc2
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  34:	fc ff df 
  37:	48 8b 54 24 20       	mov    0x20(%rsp),%rdx
  3c:	48 c1 ea 03          	shr    $0x3,%rdx

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
   a:	fc ff df 
   d:	48 8b 54 24 20       	mov    0x20(%rsp),%rdx
  12:	48 c1 ea 03          	shr    $0x3,%rdx
[   12.016429][  T218] RSP: 0018:ffffc900007e7548 EFLAGS: 00010246
[   12.016688][  T218] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000001
[   12.017008][  T218] RDX: 0000000000000000 RSI: ffff888005b0ac90 RDI: ffff8880053ed0f8
[   12.017425][  T218] RBP: ffffffffadd28600 R08: 0000000000000000 R09: fffffbfff577d944
[   12.017899][  T218] R10: ffffffffabbeca27 R11: ffff8880053ec5c0 R12: 0000000000000000
[   12.018365][  T218] R13: ffff888005b0a128 R14: ffff888005b0a008 R15: ffff888005b0a000
[   12.018821][  T218] FS:  00007f65be31e1c0(0000) GS:ffff888036180000(0000) knlGS:0000000000000000
[   12.019418][  T218] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   12.019839][  T218] CR2: 00007f65b0452830 CR3: 000000000504e006 CR4: 0000000000772ef0
[   12.020366][  T218] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   12.021150][  T218] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   12.021687][  T218] PKRU: 55555554
[   12.021957][  T218] Call Trace:
[   12.022248][  T218]  <TASK>
[ 12.022446][ T218] ? __netdev_update_features (./include/net/netdev_lock.h:52 ./include/net/netdev_lock.h:49 net/core/dev.c:10566) 
[ 12.022802][ T218] ? __warn (kernel/panic.c:748) 
[ 12.023067][ T218] ? __netdev_update_features (./include/net/netdev_lock.h:52 ./include/net/netdev_lock.h:49 net/core/dev.c:10566) 
[ 12.023447][ T218] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[ 12.023814][ T218] ? handle_bug (arch/x86/kernel/traps.c:285) 
[ 12.024075][ T218] ? exc_invalid_op (arch/x86/kernel/traps.c:309 (discriminator 1)) 
[ 12.024439][ T218] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:621) 
[ 12.024816][ T218] ? __netdev_update_features (./include/net/netdev_lock.h:52 ./include/net/netdev_lock.h:49 net/core/dev.c:10566) 
[ 12.025172][ T218] ? __netdev_update_features (./include/net/netdev_lock.h:52 net/core/dev.c:10566) 
[ 12.025551][ T218] ? __pfx___netdev_update_features (net/core/dev.c:10559) 
[ 12.025980][ T218] ? _raw_spin_unlock_irq (./arch/x86/include/asm/irqflags.h:42 ./arch/x86/include/asm/irqflags.h:97 ./include/linux/spinlock_api_smp.h:159 kernel/locking/spinlock.c:202) 
[ 12.026358][ T218] ? netdev_register_kobject (net/core/net-sysfs.c:2344) 
[ 12.026724][ T218] register_netdevice (net/core/dev.c:11003) 
[ 12.027070][ T218] ? __pfx_register_netdevice (net/core/dev.c:10881) 
[ 12.027316][ T218] nsim_create (drivers/net/netdevsim/netdev.c:958 drivers/net/netdevsim/netdev.c:1018) netdevsim 
[ 12.027559][ T218] __nsim_dev_port_add (drivers/net/netdevsim/dev.c:1393) netdevsim 
[ 12.027851][ T218] ? __pfx___nsim_dev_port_add (drivers/net/netdevsim/dev.c:1357) netdevsim 
[ 12.028141][ T218] ? nsim_dev_hwstats_init (./include/linux/workqueue.h:817 drivers/net/netdevsim/hwstats.c:442) netdevsim 
[ 12.028437][ T218] nsim_drv_probe (drivers/net/netdevsim/dev.c:1450 drivers/net/netdevsim/dev.c:1607) netdevsim 
[ 12.028673][ T218] ? __pfx_nsim_drv_probe (drivers/net/netdevsim/dev.c:1528) netdevsim 
[ 12.028972][ T218] ? kernfs_create_link (fs/kernfs/symlink.c:48) 
[ 12.029217][ T218] ? kernfs_put (./arch/x86/include/asm/atomic.h:67 (discriminator 1) ./include/linux/atomic/atomic-arch-fallback.h:2278 (discriminator 1) ./include/linux/atomic/atomic-instrumented.h:1384 (discriminator 1) fs/kernfs/dir.c:557 (discriminator 1)) 
[ 12.029386][ T218] ? sysfs_do_create_link_sd (fs/sysfs/symlink.c:48) 
[ 12.029616][ T218] really_probe (drivers/base/dd.c:579 drivers/base/dd.c:658) 
[ 12.029849][ T218] __driver_probe_device (drivers/base/dd.c:800) 
[ 12.030071][ T218] driver_probe_device (drivers/base/dd.c:830) 
[ 12.030305][ T218] __device_attach_driver (drivers/base/dd.c:959) 
[ 12.030528][ T218] ? __pfx___device_attach_driver (drivers/base/dd.c:922) 
[ 12.030820][ T218] bus_for_each_drv (drivers/base/bus.c:462) 
[ 12.031035][ T218] ? __pfx_bus_for_each_drv (drivers/base/bus.c:450) 
[ 12.031249][ T218] ? bus_to_subsys (drivers/base/bus.c:85) 
[ 12.031455][ T218] ? __pfx___lock_release (kernel/locking/lockdep.c:5503) 
[ 12.031668][ T218] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5816) 
[ 12.031883][ T218] __device_attach (drivers/base/dd.c:1030) 
[ 12.032082][ T218] ? __pfx___device_attach (drivers/base/dd.c:1001) 
[ 12.032299][ T218] ? bus_to_subsys (drivers/base/bus.c:85) 
[ 12.032498][ T218] ? do_raw_spin_unlock (./arch/x86/include/asm/atomic.h:23 ./include/linux/atomic/atomic-arch-fallback.h:457 ./include/linux/atomic/atomic-instrumented.h:33 ./include/asm-generic/qspinlock.h:57 kernel/locking/spinlock_debug.c:101 kernel/locking/spinlock_debug.c:141) 
[ 12.032705][ T218] bus_probe_device (drivers/base/bus.c:537) 
[ 12.032922][ T218] device_add (drivers/base/core.c:3672) 
[ 12.033128][ T218] ? __pfx_device_add (drivers/base/core.c:3548) 
[ 12.033341][ T218] ? __init_waitqueue_head (./include/linux/list.h:37 kernel/sched/wait.c:12) 
[ 12.033548][ T218] new_device_store (drivers/net/netdevsim/bus.c:443 drivers/net/netdevsim/bus.c:173) netdevsim 
[ 12.033826][ T218] ? __pfx_new_device_store (drivers/net/netdevsim/bus.c:142) netdevsim 
[ 12.034084][ T218] ? __pfx_sysfs_kf_write (fs/sysfs/file.c:132) 
[ 12.034292][ T218] ? sysfs_file_ops (fs/sysfs/file.c:31 (discriminator 1)) 
[ 12.034518][ T218] ? __pfx_sysfs_kf_write (fs/sysfs/file.c:132) 
[ 12.034723][ T218] kernfs_fop_write_iter (fs/kernfs/file.c:334) 
[ 12.034934][ T218] vfs_write (fs/read_write.c:586 fs/read_write.c:679) 
[ 12.035094][ T218] ? __pfx_vfs_write (fs/read_write.c:660) 
[ 12.035434][ T218] ? __lock_release (kernel/locking/lockdep.c:5527) 
[ 12.035633][ T218] ? do_user_addr_fault (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 ./include/linux/mm.h:742 arch/x86/mm/fault.c:1339) 
[ 12.035885][ T218] ? __pfx___up_read (kernel/locking/rwsem.c:1337) 
[ 12.036154][ T218] ksys_write (fs/read_write.c:731) 
[ 12.036402][ T218] ? __pfx_ksys_write (fs/read_write.c:721) 
[ 12.036708][ T218] ? do_user_addr_fault (./include/linux/rcupdate.h:882 ./include/linux/mm.h:742 arch/x86/mm/fault.c:1339) 
[ 12.037018][ T218] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[ 12.037380][ T218] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
[   12.037775][  T218] RIP: 0033:0x7f65be538b77
[ 12.038129][ T218] Code: 0b 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:	0b 00                	or     (%rax),%eax
   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
[   12.039332][  T218] RSP: 002b:00007ffd33736568 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[   12.039854][  T218] RAX: ffffffffffffffda RBX: 00007f65be31e140 RCX: 00007f65be538b77
[   12.040371][  T218] RDX: 0000000000000008 RSI: 0000555d871115b0 RDI: 0000000000000005
[   12.040886][  T218] RBP: 0000000000000008 R08: 0000000000000000 R09: 0000000000000000
[   12.041390][  T218] R10: 0000000000000002 R11: 0000000000000246 R12: 00007f65b01cf580


Finger prints:
__netdev_update_features:register_netdevice:nsim_create:__nsim_dev_port_add:nsim_drv_probe