[openib-general] [PATCH 1/2] rdma_cm: add support to join IPOIB multicast groups

[Sean Hefty]

> However, it is possible that an RDMA_PS_IPOIB consumer would want to
> talk over ---one-- UD QP with two peers:
> 
> 1) IPoIB - multicast traffic
> 2) --another-- RDMA CM consumer - unicast traffic

My thinking on this was that path record lookup and SIDR resolution isn't part 
of the ipoib protocol, and I wanted to limit the scope of the patch.

After the user joins the multicast group, unicast traffic is still supported. 
The issue I see is whether the rdma_cm uses address resolution (which ends up 
being IP ARP), an SA query, and SIDR to resolve the remote QPN, or if it can 
obtain it through some other method.

- Sean