======================================
| [    4.660622] IPv6: vlan20-v: IPv6 duplicate address fe80::200:5eff:fe00:101 used by 00:00:5e:00:01:01 detected!
| [    9.603059] ------------[ cut here ]------------
| [    9.603110] kernel BUG at net/core/skbuff.c:3505!
| [    9.603150] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
[    9.603243] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[    9.603312] RIP: 0010:__skb_checksum (net/core/skbuff.c:3505 (discriminator 1)) 
[ 9.603362] Code: 89 5c 24 04 44 89 d9 44 89 ff 44 89 ea ff d0 0f 1f 00 44 8b 5c 24 04 41 89 c7 eb b6 ff d0 0f 1f 00 41 89 c1 e9 71 fd ff ff 90 <0f> 0b 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90
All code
========
   0:	89 5c 24 04          	mov    %ebx,0x4(%rsp)
   4:	44 89 d9             	mov    %r11d,%ecx
   7:	44 89 ff             	mov    %r15d,%edi
   a:	44 89 ea             	mov    %r13d,%edx
   d:	ff d0                	call   *%rax
   f:	0f 1f 00             	nopl   (%rax)
  12:	44 8b 5c 24 04       	mov    0x4(%rsp),%r11d
  17:	41 89 c7             	mov    %eax,%r15d
  1a:	eb b6                	jmp    0xffffffffffffffd2
  1c:	ff d0                	call   *%rax
  1e:	0f 1f 00             	nopl   (%rax)
  21:	41 89 c1             	mov    %eax,%r9d
  24:	e9 71 fd ff ff       	jmp    0xfffffffffffffd9a
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	66 66 2e 0f 1f 84 00 	data16 cs nopw 0x0(%rax,%rax,1)
  33:	00 00 00 00 
  37:	90                   	nop
  38:	90                   	nop
  39:	90                   	nop
  3a:	90                   	nop
  3b:	90                   	nop
  3c:	90                   	nop
  3d:	90                   	nop
  3e:	90                   	nop
  3f:	90                   	nop

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	66 66 2e 0f 1f 84 00 	data16 cs nopw 0x0(%rax,%rax,1)
   9:	00 00 00 00 
   d:	90                   	nop
   e:	90                   	nop
   f:	90                   	nop
  10:	90                   	nop
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
[    9.603484] RSP: 0018:ffffae9400114db0 EFLAGS: 00010202
[    9.603525] RAX: 0000000000000040 RBX: 0000000000000000 RCX: 0000000000000000
[    9.603573] RDX: ffff8e0b81b4cc40 RSI: 0000000000000100 RDI: ffff8e0b81b4cb40
[    9.603622] RBP: ffffae9400114e08 R08: ffffae9400114e08 R09: 0000000000000000
[    9.603671] R10: 0000000000000000 R11: 0000000000000001 R12: ffffffffab4bba80
[    9.603719] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
[    9.603769] FS:  00007ff8b7b02300(0000) GS:ffff8e0bbed00000(0000) knlGS:0000000000000000
[    9.603830] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    9.603870] CR2: 00007fff4b0bbff8 CR3: 00000000025d8001 CR4: 0000000000770ef0
[    9.603918] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[    9.603965] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[    9.604012] PKRU: 55555554
[    9.604032] Call Trace:
[    9.604056]  <IRQ>
[    9.604077] ? die (arch/x86/kernel/dumpstack.c:421 arch/x86/kernel/dumpstack.c:434 arch/x86/kernel/dumpstack.c:447) 
[    9.604119] ? do_trap (arch/x86/kernel/traps.c:113 arch/x86/kernel/traps.c:154) 
[    9.604150] ? __skb_checksum (net/core/skbuff.c:3505 (discriminator 1)) 
[    9.604176] ? do_error_trap (./arch/x86/include/asm/traps.h:58 arch/x86/kernel/traps.c:175) 
[    9.604203] ? __skb_checksum (net/core/skbuff.c:3505 (discriminator 1)) 
[    9.604231] ? exc_invalid_op (arch/x86/kernel/traps.c:265) 
[    9.604262] ? __skb_checksum (net/core/skbuff.c:3505 (discriminator 1)) 
[    9.604291] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[    9.604324] ? __skb_checksum (net/core/skbuff.c:3505 (discriminator 1)) 
[    9.604361] __skb_checksum_complete (./arch/x86/include/asm/checksum_64.h:170 ./arch/x86/include/asm/checksum_64.h:180 net/core/skbuff.c:3643) 
[    9.604403] ? __pfx_csum_partial_ext (./include/net/checksum.h:120) 
[    9.604441] ? __pfx_csum_block_add_ext (./include/net/checksum.h:103) 
[    9.604475] icmp_rcv (./include/linux/skbuff.h:4567 net/ipv4/icmp.c:1213) 
[    9.604520] ip_protocol_deliver_rcu (net/ipv4/ip_input.c:205 (discriminator 5)) 
[    9.604561] ip_local_deliver_finish (./include/linux/rcupdate.h:782 net/ipv4/ip_input.c:234) 
[    9.604597] __netif_receive_skb_one_core (net/core/dev.c:5610 (discriminator 4)) 
[    9.604637] process_backlog (./include/linux/rcupdate.h:782 net/core/dev.c:6053) 
[    9.604667] __napi_poll (net/core/dev.c:6703) 
[    9.604695] net_rx_action (net/core/dev.c:6774 net/core/dev.c:6886) 
[    9.604726] __do_softirq (kernel/softirq.c:553) 
[    9.604760] do_softirq (kernel/softirq.c:454 kernel/softirq.c:441) 
[    9.604791]  </IRQ>
[    9.604811]  <TASK>
[    9.604831] __local_bh_enable_ip (kernel/softirq.c:381) 
[    9.604859] __dev_queue_xmit (net/core/dev.c:4400) 
[    9.604889] ? vrf_l3_out (drivers/net/vrf.c:997 drivers/net/vrf.c:1016 drivers/net/vrf.c:1029) vrf
[    9.604923] ? eth_header (net/ethernet/eth.c:85) 
[    9.604950] ip_finish_output2 (./include/net/neighbour.h:542 net/ipv4/ip_output.c:235) 
[    9.604977] ? __ip_finish_output (./include/linux/skbuff.h:4942 net/ipv4/ip_output.c:307 net/ipv4/ip_output.c:295) 
[    9.605012] 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) 
[    9.605049] raw_sendmsg (net/ipv4/raw.c:648) 
[    9.605083] ? __pte_offset_map (./include/linux/pgtable.h:298 ./include/linux/pgtable.h:518 mm/pgtable-generic.c:287) 
[    9.605115] ? __sys_sendto (net/socket.c:730 net/socket.c:745 net/socket.c:2191) 
[    9.605146] __sys_sendto (net/socket.c:730 net/socket.c:745 net/socket.c:2191) 
[    9.605176] ? handle_mm_fault (mm/memory.c:5330 mm/memory.c:5486) 
[    9.605209] ? do_user_addr_fault (./include/linux/rcupdate.h:782 ./include/linux/mm.h:688 arch/x86/mm/fault.c:1357) 
[    9.605247] __x64_sys_sendto (net/socket.c:2203 net/socket.c:2199 net/socket.c:2199) 
[    9.605274] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[    9.605308] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:129) 
[    9.605355] RIP: 0033:0x7ff8b7dd885a
[ 9.605384] 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
[    9.605488] RSP: 002b:00007fff4b0bcd08 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
[    9.605536] RAX: ffffffffffffffda RBX: 0000000000000038 RCX: 00007ff8b7dd885a
[    9.605584] RDX: 0000000000000040 RSI: 00000000004da340 RDI: 0000000000000005
[    9.605632] RBP: 00007fff4b0bcd60 R08: 00000000004185e0 R09: 0000000000000010
[    9.605680] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000054


Finger prints:
__skb_checksum:__skb_checksum_complete:icmp_rcv:ip_protocol_deliver_rcu