Hi Vincent,

[auto build test WARNING on net-next/master]

url:    https://github.com/0day-ci/linux/commits/Vincent-Bernat/vxlan-fix-ND-proxy-when-skb-doesn-t-have-transport-header-offset/20170401-182312
config: x86_64-randconfig-v0-04020359 (attached as .config)
compiler: gcc-4.4 (Debian 4.4.7-8) 4.4.7
reproduce:
        # save the attached .config to linux build tree
        make ARCH=x86_64 

All warnings (new ones prefixed by >>):

   drivers//net/vxlan.c: In function 'vxlan_xmit':
>> drivers//net/vxlan.c:2245: warning: unused variable '_hdr'
>> drivers//net/vxlan.c:2245: warning: unused variable 'hdr'

vim +/_hdr +2245 drivers//net/vxlan.c

  2229		skb_reset_mac_header(skb);
  2230	
  2231		if (vxlan->flags & VXLAN_F_COLLECT_METADATA) {
  2232			if (info && info->mode & IP_TUNNEL_INFO_BRIDGE &&
  2233			    info->mode & IP_TUNNEL_INFO_TX) {
  2234				vni = tunnel_id_to_key32(info->key.tun_id);
  2235			} else {
  2236				if (info && info->mode & IP_TUNNEL_INFO_TX)
  2237					vxlan_xmit_one(skb, dev, vni, NULL, false);
  2238				else
  2239					kfree_skb(skb);
  2240				return NETDEV_TX_OK;
  2241			}
  2242		}
  2243	
  2244		if (vxlan->flags & VXLAN_F_PROXY) {
> 2245			struct ipv6hdr *hdr, _hdr;
  2246			eth = eth_hdr(skb);
  2247			if (ntohs(eth->h_proto) == ETH_P_ARP)
  2248				return arp_reduce(dev, skb, vni);
  2249	#if IS_ENABLED(CONFIG_IPV6)
  2250			else if (ntohs(eth->h_proto) == ETH_P_IPV6 &&
  2251				 (hdr = skb_header_pointer(skb,
  2252							   skb_network_offset(skb),
  2253							   sizeof(_hdr), &_hdr)) &&

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