[openib-general] IB mcast question

[Sean Hefty]

>The qkeys used by the RDMA CM sound like they may be the problem.  I'll verify
>this and see how to fix it if so.

If I set the qkeys for the QPs and MCMemberRecord to 0, I can get this to work
now.  The RDMA CM uses a qkey = port number for UD QPs, and a qkey = IPv4
address for MCMemberRecords.

A potential fix I see for this is to use the same qkey for all UD QPs and
multicast groups created by the RDMA CM.  Otherwise we restrict UD QPs to using
a single destination (remote UD QP or multicast group.)

- Sean