======================================
| xx__-> [   17.806627][  T226] packetdrill (226) used greatest stack depth: 23664 bytes left
| [   18.200154][  T258] ------------[ cut here ]------------
| [ 18.200730][ T258] WARNING: CPU: 2 PID: 258 at ./include/net/netdev_lock.h:17 netif_set_mtu_ext (./include/net/netdev_lock.h:17 ./include/net/netdev_lock.h:15 ./include/net/netdev_lock.h:25 net/core/dev.c:9610) 
| [   18.201384][  T258] Modules linked in:
[   18.202236][  T258] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[ 18.202643][ T258] RIP: 0010:netif_set_mtu_ext (./include/net/netdev_lock.h:17 ./include/net/netdev_lock.h:15 ./include/net/netdev_lock.h:25 net/core/dev.c:9610) 
[ 18.202974][ T258] Code: 00 00 8b 05 a7 0e 19 02 85 c0 0f 84 52 fe ff ff 48 8d bb 80 0c 00 00 be ff ff ff ff e8 ea 9c 74 00 85 c0 0f 85 39 fe ff ff 90 <0f> 0b 90 e9 30 fe ff ff 48 b8 00 00 00 00 00 fc ff df 4c 89 fa 48
All code
========
   0:	00 00                	add    %al,(%rax)
   2:	8b 05 a7 0e 19 02    	mov    0x2190ea7(%rip),%eax        # 0x2190eaf
   8:	85 c0                	test   %eax,%eax
   a:	0f 84 52 fe ff ff    	je     0xfffffffffffffe62
  10:	48 8d bb 80 0c 00 00 	lea    0xc80(%rbx),%rdi
  17:	be ff ff ff ff       	mov    $0xffffffff,%esi
  1c:	e8 ea 9c 74 00       	call   0x749d0b
  21:	85 c0                	test   %eax,%eax
  23:	0f 85 39 fe ff ff    	jne    0xfffffffffffffe62
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	e9 30 fe ff ff       	jmp    0xfffffffffffffe62
  32:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  39:	fc ff df 
  3c:	4c 89 fa             	mov    %r15,%rdx
  3f:	48                   	rex.W

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	e9 30 fe ff ff       	jmp    0xfffffffffffffe38
   8:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
   f:	fc ff df 
  12:	4c 89 fa             	mov    %r15,%rdx
  15:	48                   	rex.W
[   18.204069][  T258] RSP: 0018:ffffc90000a87930 EFLAGS: 00010246
[   18.204497][  T258] RAX: 0000000000000000 RBX: ffff88800ab90000 RCX: 0000000000000001
[   18.204965][  T258] RDX: 0000000000000000 RSI: ffffffff85288ba1 RDI: ffffffff84a555a0
[   18.205444][  T258] RBP: ffffc90000a87a18 R08: ffff88800ab90008 R09: 0000000000000000
[   18.206207][  T258] R10: ffffc90000a87a48 R11: ffffffff86050068 R12: 1ffff92000150f2a
[   18.206683][  T258] R13: 00000000000005f0 R14: ffffc90000a87a48 R15: ffffc90000a87d40
[   18.207149][  T258] FS:  00007f0edafd6740(0000) GS:ffff8880aeff1000(0000) knlGS:0000000000000000
[   18.207693][  T258] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   18.208083][  T258] CR2: 000055a1f713e5e6 CR3: 00000000050db003 CR4: 0000000000772ef0
[   18.208576][  T258] PKRU: 55555554
[   18.208822][  T258] Call Trace:
[   18.209060][  T258]  <TASK>
[ 18.209234][ T258] ? __pfx_netif_set_mtu_ext (net/core/dev.c:9607) 
[ 18.209565][ T258] ? rcu_read_lock_any_held (kernel/rcu/update.c:386 kernel/rcu/update.c:380) 
[ 18.209884][ T258] ? validate_chain (kernel/locking/lockdep.c:3804 kernel/locking/lockdep.c:3824 kernel/locking/lockdep.c:3879) 
[ 18.210203][ T258] ? rcu_read_lock_any_held (kernel/rcu/update.c:386 kernel/rcu/update.c:380) 
[ 18.210522][ T258] ? validate_chain (kernel/locking/lockdep.c:3804 kernel/locking/lockdep.c:3824 kernel/locking/lockdep.c:3879) 
[ 18.210834][ T258] netif_set_mtu (net/core/dev.c:9652) 
[ 18.211151][ T258] ? __pfx_netif_set_mtu (net/core/dev.c:9647) 
[ 18.211485][ T258] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 18.211814][ T258] dev_set_mtu (./include/net/netdev_lock.h:30 ./include/net/netdev_lock.h:47 net/core/dev_api.c:249) 
[ 18.212059][ T258] dev_ifsioc (net/core/dev_ioctl.c:572) 
[ 18.212382][ T258] ? __pfx_dev_ifsioc (net/core/dev_ioctl.c:553) 
[ 18.212697][ T258] ? __pfx___mutex_lock (kernel/locking/mutex.c:746) 
[ 18.213017][ T258] ? find_held_lock (kernel/locking/lockdep.c:5353) 
[ 18.213342][ T258] ? dev_load (./include/linux/rcupdate.h:341 ./include/linux/rcupdate.h:871 net/core/dev_ioctl.c:678) 
[ 18.213584][ T258] ? __lock_release (kernel/locking/lockdep.c:5539) 
[ 18.213913][ T258] dev_ioctl (net/core/dev_ioctl.c:824) 
[ 18.214161][ T258] sock_do_ioctl (net/socket.c:1252) 
[ 18.214494][ T258] ? __pfx_sock_do_ioctl (net/socket.c:1230) 
[ 18.214804][ T258] ? __pmd_alloc (./include/linux/mm.h:1512 ./include/linux/mm.h:1738 ./include/linux/mm.h:1748 ./include/linux/vmstat.h:578 ./include/linux/vmstat.h:610 ./include/linux/mm.h:2971 ./include/linux/mm.h:2976 ./include/asm-generic/pgalloc.h:160 mm/memory.c:6477) 
[ 18.215114][ T258] ? lock_vma_under_rcu (./include/linux/rcupdate.h:341 ./include/linux/rcupdate.h:871 mm/mmap_lock.c:171) 
[ 18.215436][ T258] ? __lock_release (kernel/locking/lockdep.c:5585) 
[ 18.215766][ T258] sock_ioctl (net/socket.c:1362) 
[ 18.216008][ T258] ? __pfx_sock_ioctl (net/socket.c:1266) 
[ 18.216329][ T258] ? find_held_lock (kernel/locking/lockdep.c:5353) 
[ 18.216648][ T258] ? exc_page_fault (./arch/x86/include/asm/irqflags.h:26 ./arch/x86/include/asm/irqflags.h:109 ./arch/x86/include/asm/irqflags.h:151 arch/x86/mm/fault.c:1484 arch/x86/mm/fault.c:1532) 
[ 18.216960][ T258] ? __lock_release (kernel/locking/lockdep.c:5539) 
[ 18.217289][ T258] ? exc_page_fault (./arch/x86/include/asm/irqflags.h:26 ./arch/x86/include/asm/irqflags.h:109 ./arch/x86/include/asm/irqflags.h:151 arch/x86/mm/fault.c:1484 arch/x86/mm/fault.c:1532) 
[ 18.217614][ T258] __x64_sys_ioctl (fs/ioctl.c:52 fs/ioctl.c:907 fs/ioctl.c:893 fs/ioctl.c:893) 
[ 18.217941][ T258] do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94) 
[ 18.218257][ T258] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
[   18.218652][  T258] RIP: 0033:0x7f0edb0dce4b
[ 18.218975][ T258] Code: ff ff ff 85 c0 79 9b 49 c7 c4 ff ff ff ff 5b 5d 4c 89 e0 41 5c c3 66 0f 1f 84 00 00 00 00 00 f3 0f 1e fa b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 7d 4f 0f 00 f7 d8 64 89 01 48
All code
========
   0:	ff                   	(bad)
   1:	ff                   	(bad)
   2:	ff 85 c0 79 9b 49    	incl   0x499b79c0(%rbp)
   8:	c7 c4 ff ff ff ff    	mov    $0xffffffff,%esp
   e:	5b                   	pop    %rbx
   f:	5d                   	pop    %rbp
  10:	4c 89 e0             	mov    %r12,%rax
  13:	41 5c                	pop    %r12
  15:	c3                   	ret
  16:	66 0f 1f 84 00 00 00 	nopw   0x0(%rax,%rax,1)
  1d:	00 00 
  1f:	f3 0f 1e fa          	endbr64
  23:	b8 10 00 00 00       	mov    $0x10,%eax
  28:	0f 05                	syscall
  2a:*	48 3d 01 f0 ff ff    	cmp    $0xfffffffffffff001,%rax		<-- trapping instruction
  30:	73 01                	jae    0x33
  32:	c3                   	ret
  33:	48 8b 0d 7d 4f 0f 00 	mov    0xf4f7d(%rip),%rcx        # 0xf4fb7
  3a:	f7 d8                	neg    %eax
  3c:	64 89 01             	mov    %eax,%fs:(%rcx)
  3f:	48                   	rex.W

Code starting with the faulting instruction
===========================================
   0:	48 3d 01 f0 ff ff    	cmp    $0xfffffffffffff001,%rax
   6:	73 01                	jae    0x9
   8:	c3                   	ret
   9:	48 8b 0d 7d 4f 0f 00 	mov    0xf4f7d(%rip),%rcx        # 0xf4f8d
  10:	f7 d8                	neg    %eax
  12:	64 89 01             	mov    %eax,%fs:(%rcx)
  15:	48                   	rex.W
[   18.220056][  T258] RSP: 002b:00007ffec5f9f738 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
[   18.220540][  T258] RAX: ffffffffffffffda RBX: 00007ffec5f9fa98 RCX: 00007f0edb0dce4b
[   18.221011][  T258] RDX: 00007ffec5f9f790 RSI: 0000000000008922 RDI: 0000000000000007
[   18.221483][  T258] RBP: 00007ffec5f9faa8 R08: 1999999999999999 R09: 0000000000000000
[   18.221966][  T258] R10: 00007f0edb177ac0 R11: 0000000000000246 R12: 00007ffec5fa09a2


Finger prints:
netif_set_mtu_ext:netif_set_mtu:dev_set_mtu:dev_ifsioc:dev_ioctl