======================================
| [   37.658959][  T307] l2tp_ip6: L2TP IP encapsulation support for IPv6 (L2TPv3)
| [   39.283017][    C3] ------------[ cut here ]------------
| [   39.283458][    C3] kernel BUG at net/core/skbuff.c:3505!
| [   39.283755][    C3] invalid opcode: 0000 [#1] PREEMPT SMP KASAN NOPTI
[   39.284375][    C3] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[ 39.284920][ C3] RIP: 0010:__skb_checksum (net/core/skbuff.c:3505 (discriminator 1)) 
[ 39.285158][ C3] Code: 44 89 14 24 ff d0 0f 1f 00 4c 8b 44 24 08 44 8b 14 24 41 89 c1 eb a5 89 e8 e9 2d fe ff ff 41 ff d5 0f 1f 00 e9 1f fa ff ff 90 <0f> 0b 48 8b 7c 24 10 89 54 24 48 48 89 44 24 40 e8 e7 53 8d fe 8b
All code
========
   0:	44 89 14 24          	mov    %r10d,(%rsp)
   4:	ff d0                	call   *%rax
   6:	0f 1f 00             	nopl   (%rax)
   9:	4c 8b 44 24 08       	mov    0x8(%rsp),%r8
   e:	44 8b 14 24          	mov    (%rsp),%r10d
  12:	41 89 c1             	mov    %eax,%r9d
  15:	eb a5                	jmp    0xffffffffffffffbc
  17:	89 e8                	mov    %ebp,%eax
  19:	e9 2d fe ff ff       	jmp    0xfffffffffffffe4b
  1e:	41 ff d5             	call   *%r13
  21:	0f 1f 00             	nopl   (%rax)
  24:	e9 1f fa ff ff       	jmp    0xfffffffffffffa48
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	48 8b 7c 24 10       	mov    0x10(%rsp),%rdi
  31:	89 54 24 48          	mov    %edx,0x48(%rsp)
  35:	48 89 44 24 40       	mov    %rax,0x40(%rsp)
  3a:	e8 e7 53 8d fe       	call   0xfffffffffe8d5426
  3f:	8b                   	.byte 0x8b

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	48 8b 7c 24 10       	mov    0x10(%rsp),%rdi
   7:	89 54 24 48          	mov    %edx,0x48(%rsp)
   b:	48 89 44 24 40       	mov    %rax,0x40(%rsp)
  10:	e8 e7 53 8d fe       	call   0xfffffffffe8d53fc
  15:	8b                   	.byte 0x8b
[   39.285951][    C3] RSP: 0018:ffffc90000278920 EFLAGS: 00010202
[   39.286244][    C3] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 1ffff1100106f6d9
[   39.286570][    C3] RDX: 0000000000000040 RSI: 0000000000000000 RDI: ffff88800837b6c8
[   39.286898][    C3] RBP: 0000000000000000 R08: ffffc900002789e0 R09: fffffbfff40ea5a2
[   39.287234][    C3] R10: ffffffffa0752d17 R11: ffffc90000278b20 R12: 0000000000000000
[   39.287588][    C3] R13: 0000000000000000 R14: ffffc900002789e0 R15: ffff888002a29408
[   39.287938][    C3] FS:  00007f431cf28300(0000) GS:ffff88802f780000(0000) knlGS:0000000000000000
[   39.288347][    C3] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   39.288650][    C3] CR2: 00007ffc6af00fb0 CR3: 0000000002c0c002 CR4: 0000000000770ef0
[   39.288995][    C3] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   39.289228][    C3] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   39.289460][    C3] PKRU: 55555554
[   39.289573][    C3] Call Trace:
[   39.289686][    C3]  <IRQ>
[ 39.289763][ C3] ? die (arch/x86/kernel/dumpstack.c:421 arch/x86/kernel/dumpstack.c:434 arch/x86/kernel/dumpstack.c:447) 
[ 39.289881][ C3] ? do_trap (arch/x86/kernel/traps.c:113 arch/x86/kernel/traps.c:154) 
[ 39.289995][ C3] ? __skb_checksum (net/core/skbuff.c:3505 (discriminator 1)) 
[ 39.290147][ C3] ? do_error_trap (./arch/x86/include/asm/traps.h:58 arch/x86/kernel/traps.c:175) 
[ 39.290293][ C3] ? __skb_checksum (net/core/skbuff.c:3505 (discriminator 1)) 
[ 39.290479][ C3] ? __skb_checksum (net/core/skbuff.c:3505 (discriminator 1)) 
[ 39.290627][ C3] ? handle_invalid_op (arch/x86/kernel/traps.c:213) 
[ 39.290775][ C3] ? __skb_checksum (net/core/skbuff.c:3505 (discriminator 1)) 
[ 39.290922][ C3] ? exc_invalid_op (arch/x86/kernel/traps.c:265) 
[ 39.291074][ C3] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[ 39.291225][ C3] ? __skb_checksum (net/core/skbuff.c:3505 (discriminator 1)) 
[ 39.291375][ C3] __skb_checksum_complete (net/core/skbuff.c:3643) 
[ 39.291533][ C3] ? __pfx___skb_checksum_complete (net/core/skbuff.c:3637) 
[ 39.291718][ C3] ? __pfx_csum_partial_ext (./include/net/checksum.h:120) 
[ 39.291868][ C3] ? __pfx_csum_block_add_ext (./include/net/checksum.h:103) 
[ 39.292016][ C3] icmp_rcv (./include/linux/skbuff.h:4567 net/ipv4/icmp.c:1213) 
[ 39.292131][ C3] ip_protocol_deliver_rcu (net/ipv4/ip_input.c:205 (discriminator 5)) 
[ 39.292284][ C3] ip_local_deliver_finish (./include/linux/rcupdate.h:779 net/ipv4/ip_input.c:234) 
[ 39.292439][ C3] ip_local_deliver (./include/linux/netfilter.h:314 ./include/linux/netfilter.h:308 net/ipv4/ip_input.c:254) 
[ 39.292590][ C3] ? __pfx_ip_local_deliver (net/ipv4/ip_input.c:243) 
[ 39.292740][ C3] ? ip_rcv_finish_core.constprop.0 (./include/linux/skbuff.h:1136 ./include/linux/skbuff.h:1188 net/ipv4/ip_input.c:390) 
[ 39.292928][ C3] ip_rcv (./include/net/dst.h:460 net/ipv4/ip_input.c:449 ./include/linux/netfilter.h:314 ./include/linux/netfilter.h:308 net/ipv4/ip_input.c:569) 
[ 39.293039][ C3] ? __pfx_ip_rcv (net/ipv4/ip_input.c:562) 
[ 39.293187][ C3] ? lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5756) 
[ 39.293339][ C3] ? process_backlog (./include/linux/rcupdate.h:298 ./include/linux/rcupdate.h:750 net/core/dev.c:6051) 
[ 39.293500][ C3] ? __pfx_ip_rcv (net/ipv4/ip_input.c:562) 
[ 39.293649][ C3] __netif_receive_skb_one_core (net/core/dev.c:5610 (discriminator 4)) 
[ 39.293834][ C3] ? __pfx___netif_receive_skb_one_core (net/core/dev.c:5603) 
[ 39.294018][ C3] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5725) 
[ 39.294170][ C3] ? process_backlog (./include/linux/rcupdate.h:298 ./include/linux/rcupdate.h:750 net/core/dev.c:6051) 
[ 39.294323][ C3] process_backlog (./include/linux/rcupdate.h:779 net/core/dev.c:6053) 
[ 39.294476][ C3] ? find_held_lock (kernel/locking/lockdep.c:5244) 
[ 39.294627][ C3] __napi_poll.constprop.0 (net/core/dev.c:6703) 
[ 39.294775][ C3] net_rx_action (net/core/dev.c:6772 net/core/dev.c:6886) 
[ 39.294926][ C3] ? __pfx_net_rx_action (net/core/dev.c:6850) 
[ 39.295073][ C3] ? usage_skip (kernel/locking/lockdep.c:2295 kernel/locking/lockdep.c:2263) 
[ 39.295221][ C3] ? mark_held_locks (kernel/locking/lockdep.c:4274) 
[ 39.295369][ C3] ? hrtimer_interrupt (kernel/time/hrtimer.c:1828) 
[ 39.295622][ C3] __do_softirq (kernel/softirq.c:553) 
[ 39.295772][ C3] ? __neigh_event_send (./include/linux/bottom_half.h:33 net/core/neighbour.c:1245) 
[ 39.295919][ C3] do_softirq (kernel/softirq.c:454 kernel/softirq.c:441) 
[   39.296032][    C3]  </IRQ>
[   39.296122][    C3]  <TASK>
[ 39.296199][ C3] __local_bh_enable_ip (kernel/softirq.c:381) 
[ 39.296473][ C3] __neigh_event_send (./arch/x86/include/asm/jump_label.h:27 ./include/linux/jump_label.h:207 ./include/trace/events/neigh.h:237 net/core/neighbour.c:1246) 
[ 39.296638][ C3] neigh_resolve_output (net/core/neighbour.c:1547) 
[ 39.296784][ C3] ? __local_bh_enable_ip (./arch/x86/include/asm/irqflags.h:42 ./arch/x86/include/asm/irqflags.h:77 kernel/softirq.c:386) 
[ 39.296939][ C3] ? ___neigh_create (net/core/neighbour.c:722 (discriminator 9)) 
[ 39.297178][ C3] ip_finish_output2 (./include/net/neighbour.h:542 net/ipv4/ip_output.c:235) 
[ 39.297351][ C3] ? __pfx_get_random_u32 (drivers/char/random.c:532) 
[ 39.297513][ C3] ? __lock_acquire (kernel/locking/lockdep.c:5137) 
[ 39.297662][ C3] ? __pfx_raw_getfrag (net/ipv4/raw.c:446) 
[ 39.297989][ C3] ? __pfx_ip_finish_output2 (net/ipv4/ip_output.c:199) 
[ 39.298136][ C3] ? __ip_finish_output (./include/linux/skbuff.h:1624 ./include/linux/skbuff.h:4942 net/ipv4/ip_output.c:307 net/ipv4/ip_output.c:295) 
[ 39.298283][ C3] ip_output (./include/linux/netfilter.h:303 net/ipv4/ip_output.c:433) 
[ 39.298402][ C3] ? __ip_local_out (net/ipv4/ip_output.c:96 net/ipv4/ip_output.c:107) 
[ 39.298549][ C3] ? __pfx_ip_output (net/ipv4/ip_output.c:427) 
[ 39.298788][ C3] ? __ip_make_skb (net/ipv4/ip_output.c:1379 net/ipv4/ip_output.c:1487) 
[ 39.298936][ C3] ? __pfx_raw_getfrag (net/ipv4/raw.c:446) 
[ 39.299082][ C3] ? ip_append_data (net/ipv4/ip_output.c:1368 net/ipv4/ip_output.c:1347) 
[ 39.299229][ C3] ip_push_pending_frames (./include/net/dst.h:450 net/ipv4/ip_output.c:129 net/ipv4/ip_output.c:1496 net/ipv4/ip_output.c:1516) 
[ 39.299382][ C3] raw_sendmsg (net/ipv4/raw.c:648) 
[ 39.299535][ C3] ? __pfx_validate_chain (kernel/locking/lockdep.c:3825) 
[ 39.299687][ C3] ? __pfx_raw_sendmsg (net/ipv4/raw.c:476) 
[ 39.299833][ C3] ? __lock_acquire (kernel/locking/lockdep.c:5137) 
[ 39.300071][ C3] ? find_held_lock (kernel/locking/lockdep.c:5244) 
[ 39.300219][ C3] ? __lock_release (kernel/locking/lockdep.c:5430) 
[ 39.300365][ C3] ? __might_fault (mm/memory.c:6080 mm/memory.c:6073) 
[ 39.300525][ C3] ? __pfx___lock_release (kernel/locking/lockdep.c:5406) 
[ 39.300671][ C3] ? 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) 
[ 39.300908][ C3] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5725) 
[ 39.301056][ C3] ? __might_fault (mm/memory.c:6080 mm/memory.c:6073) 
[ 39.301209][ C3] ? __might_fault (mm/memory.c:6080 mm/memory.c:6073) 
[ 39.301357][ C3] ? __sys_sendto (net/socket.c:730 net/socket.c:745 net/socket.c:2191) 
[ 39.301602][ C3] __sys_sendto (net/socket.c:730 net/socket.c:745 net/socket.c:2191) 
[ 39.301750][ C3] ? __pfx___sys_sendto (net/socket.c:2161) 
[ 39.301897][ C3] ? do_user_addr_fault (./include/linux/rcupdate.h:298 ./include/linux/rcupdate.h:750 ./include/linux/mm.h:686 arch/x86/mm/fault.c:1357) 
[ 39.302046][ C3] ? reacquire_held_locks (kernel/locking/lockdep.c:5279) 
[ 39.302284][ C3] ? __lock_release (kernel/locking/lockdep.c:5430) 
[ 39.302436][ C3] ? do_user_addr_fault (./include/linux/rcupdate.h:308 ./include/linux/rcupdate.h:783 ./include/linux/mm.h:688 arch/x86/mm/fault.c:1357) 
[ 39.302582][ C3] ? __pfx___lock_release (kernel/locking/lockdep.c:5406) 
[ 39.302731][ C3] ? __up_read (./arch/x86/include/asm/atomic64_64.h:79 ./include/linux/atomic/atomic-arch-fallback.h:2735 ./include/linux/atomic/atomic-long.h:184 ./include/linux/atomic/atomic-instrumented.h:3289 kernel/locking/rwsem.c:1347) 
[ 39.302969][ C3] ? __pfx___up_read (kernel/locking/rwsem.c:1339) 
[ 39.303115][ C3] ? do_user_addr_fault (./include/linux/rcupdate.h:308 ./include/linux/rcupdate.h:783 ./include/linux/mm.h:688 arch/x86/mm/fault.c:1357) 
[ 39.303263][ C3] __x64_sys_sendto (net/socket.c:2199) 
[ 39.303421][ C3] ? lockdep_hardirqs_on_prepare.part.0 (kernel/locking/lockdep.c:4300 kernel/locking/lockdep.c:4359) 
[ 39.303695][ C3] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[ 39.303844][ C3] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:129) 
[   39.304030][    C3] RIP: 0033:0x7f431d1fe85a
[ 39.304185][ C3] Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 f3 0f 1e fa 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 15 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 7e c3 0f 1f 44 00 00 41 54 48 83 ec 30 44 89
All code
========
   0:	d8 64 89 02          	fsubs  0x2(%rcx,%rcx,4)
   4:	48 c7 c0 ff ff ff ff 	mov    $0xffffffffffffffff,%rax
   b:	eb b8                	jmp    0xffffffffffffffc5
   d:	0f 1f 00             	nopl   (%rax)
  10:	f3 0f 1e fa          	endbr64
  14:	41 89 ca             	mov    %ecx,%r10d
  17:	64 8b 04 25 18 00 00 	mov    %fs:0x18,%eax
  1e:	00 
  1f:	85 c0                	test   %eax,%eax
  21:	75 15                	jne    0x38
  23:	b8 2c 00 00 00       	mov    $0x2c,%eax
  28:	0f 05                	syscall
  2a:*	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax		<-- trapping instruction
  30:	77 7e                	ja     0xb0
  32:	c3                   	ret
  33:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)
  38:	41 54                	push   %r12
  3a:	48 83 ec 30          	sub    $0x30,%rsp
  3e:	44                   	rex.R
  3f:	89                   	.byte 0x89

Code starting with the faulting instruction
===========================================
   0:	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax
   6:	77 7e                	ja     0x86
   8:	c3                   	ret
   9:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)
   e:	41 54                	push   %r12
  10:	48 83 ec 30          	sub    $0x30,%rsp
  14:	44                   	rex.R
  15:	89                   	.byte 0x89
[   39.304716][    C3] RSP: 002b:00007ffc6af01ad8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
[   39.304939][    C3] RAX: ffffffffffffffda RBX: 0000000000000038 RCX: 00007f431d1fe85a
[   39.305253][    C3] RDX: 0000000000000040 RSI: 000000000136c340 RDI: 0000000000000005
[   39.305480][    C3] RBP: 00007ffc6af01b30 R08: 00000000004185e0 R09: 0000000000000010
[   39.305790][    C3] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000054


Finger prints:
__skb_checksum:__skb_checksum_complete:icmp_rcv:ip_protocol_deliver_rcu