hi Arnd, Cc'ing Alin Nastac. On Mon, Mar 04, 2019 at 09:40:12PM +0100, Arnd Bergmann wrote: > With CONFIG_IPV6=m and CONFIG_NF_CONNTRACK_SIP=y, we now get a link failure: > > net/netfilter/nf_conntrack_sip.o: In function `process_sdp': > nf_conntrack_sip.c:(.text+0x4344): undefined reference to `ip6_route_output_flags' I see. We can probably use nf_route() instead. Or if needed, use struct nf_ipv6_ops for this. if (v6ops) ret = v6ops->route_xyz(...); @Alin: Would you send us a patch to do so to fix a3419ce3356cf1f netfilter: nf_conntrack_sip: add sip_external_media logic". This direct dependency with IPv6 is superfluous, it should not happen. Thanks!