On 9/22/16 4:10 PM, Mark Tomlinson wrote: > > On 09/23/2016 03:14 AM, David Ahern wrote: >> >> l3mdev devices do not support IPv4 multicast so checking mcast against that >> device should not be working at all. For that reason I was fine with the >> change in the previous patch. ie., you want the real ingress device there >> not the vrf device. >> >> What test are you running that says your previous patch broke something? > Although we do not expect any multicast routing to work in an l3mdev, > (IGMP snooping or PIM), we still want to have multicast packets > delivered for protocols such as RIP. This was working before my previous > patch, but these multicast packets are now dropped. This current patch > fixes that again, hopefully still with the benefits of my first patch. >
can you discern which check is making that happen? It does not make sense to look at the in_device of a vrf device for mcast addresses. For IPv6 linklocal and mcast is specifically blocked. IPv4 should do the same. So, how is RIP getting the packet at all?
