======================================
| [    2.968360] br2: port 2(veth2.20) entered forwarding state
| [    3.132492] ------------[ cut here ]------------
| [    3.132561] kernel BUG at net/core/skbuff.c:3505!
| [    3.132615] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
[    3.132744] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[    3.132853] Workqueue: mld mld_ifc_work
[    3.132896] RIP: 0010:__skb_checksum (net/core/skbuff.c:3505 (discriminator 1)) 
[ 3.132953] 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
[    3.133121] RSP: 0018:ffffb41a00003db0 EFLAGS: 00010202
[    3.133183] RAX: 0000000000000092 RBX: 0000000000000008 RCX: ffff8f1002552700
[    3.133254] RDX: ffff8f10024e19c0 RSI: 0000000000000100 RDI: ffff8f10024e18c0
[    3.133323] RBP: ffffb41a00003e08 R08: ffffb41a00003e08 R09: 00000000a2790103
[    3.133395] R10: 0000000000000008 R11: 0000000000000001 R12: ffffffffa0ebba80
[    3.133464] R13: 0000000000000008 R14: 0000000000000000 R15: 00000000a2790103
[    3.133541] FS:  0000000000000000(0000) GS:ffff8f103ec00000(0000) knlGS:0000000000000000
[    3.133618] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    3.133677] CR2: 00005571134f6dec CR3: 0000000002626005 CR4: 0000000000770ef0
[    3.133748] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[    3.133831] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[    3.133906] PKRU: 55555554
[    3.133931] Call Trace:
[    3.133960]  <IRQ>
[    3.133991] ? die (arch/x86/kernel/dumpstack.c:421 arch/x86/kernel/dumpstack.c:434 arch/x86/kernel/dumpstack.c:447) 
[    3.134035] ? do_trap (arch/x86/kernel/traps.c:113 arch/x86/kernel/traps.c:154) 
[    3.134084] ? __skb_checksum (net/core/skbuff.c:3505 (discriminator 1)) 
[    3.134119] ? do_error_trap (./arch/x86/include/asm/traps.h:58 arch/x86/kernel/traps.c:175) 
[    3.134155] ? __skb_checksum (net/core/skbuff.c:3505 (discriminator 1)) 
[    3.134189] ? exc_invalid_op (arch/x86/kernel/traps.c:265) 
[    3.134234] ? __skb_checksum (net/core/skbuff.c:3505 (discriminator 1)) 
[    3.134269] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) 
[    3.134316] ? __skb_checksum (net/core/skbuff.c:3505 (discriminator 1)) 
[    3.134351] __skb_checksum_complete (./arch/x86/include/asm/checksum_64.h:170 ./arch/x86/include/asm/checksum_64.h:180 net/core/skbuff.c:3643) 
[    3.134398] ? __pfx_csum_partial_ext (./include/net/checksum.h:120) 
[    3.134451] ? __pfx_csum_block_add_ext (./include/net/checksum.h:103) 
[    3.134495] icmp_rcv (./include/linux/skbuff.h:4567 net/ipv4/icmp.c:1213) 
[    3.134538] ip_protocol_deliver_rcu (net/ipv4/ip_input.c:205 (discriminator 5)) 
[    3.134594] ip_local_deliver_finish (./include/linux/rcupdate.h:782 net/ipv4/ip_input.c:234) 
[    3.134812] __netif_receive_skb_one_core (net/core/dev.c:5610 (discriminator 4)) 
[    3.134847] process_backlog (./include/linux/rcupdate.h:782 net/core/dev.c:6053) 
[    3.134885] __napi_poll (net/core/dev.c:6703) 
[    3.134923] net_rx_action (net/core/dev.c:6774 net/core/dev.c:6886) 
[    3.134954] __do_softirq (kernel/softirq.c:553) 
[    3.134994] do_softirq (kernel/softirq.c:454 kernel/softirq.c:441) 
[    3.135026]  </IRQ>
[    3.135050]  <TASK>
[    3.135074] __local_bh_enable_ip (kernel/softirq.c:381) 
[    3.135111] __dev_queue_xmit (net/core/dev.c:4400) 
[    3.135146] ip6_finish_output2 (./include/linux/netdevice.h:3172 ./include/net/neighbour.h:526 ./include/net/neighbour.h:540 net/ipv6/ip6_output.c:137) 
[    3.135190] ip6_finish_output (net/ipv6/ip6_output.c:211 net/ipv6/ip6_output.c:222) 
[    3.135235] mld_sendpack (net/ipv6/mcast.c:1822) 
[    3.135284] mld_ifc_work (net/ipv6/mcast.c:2652) 
[    3.135325] process_one_work (kernel/workqueue.c:2633) 
[    3.135367] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[    3.135414] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[    3.135450] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[    3.135506] kthread (kernel/kthread.c:388) 
[    3.135560] ? __pfx_kthread (kernel/kthread.c:341) 
[    3.135595] ret_from_fork (arch/x86/kernel/process.c:147) 
[    3.135630] ? __pfx_kthread (kernel/kthread.c:341) 


Finger prints:
__skb_checksum:__skb_checksum_complete:icmp_rcv:ip_protocol_deliver_rcu