[openib-general] [RFC] [PATCH 2/7] ib_multicast 2.6.20: add ib_multicast module to track join requests from the same port

[Sean Hefty]

Eitan Zahavi wrote:
> User level code can be run by root. It can access QP1 and bypass your nice
> API. Also you ignore current kernel implementations that exist and already 
> perform QP1 access via the SA client code in the kernel.

Yep - and that same app can, today, delete the multicast groups used by ipoib. 
As long as a MAD can actually be sent out of QP1, we have this problem.

The existing APIs were not ignored.  The ib_multicast module makes direct calls 
to ib_sa.

> No you are forcing every kernel client out there to do another unneeded 
> migration to the new API and still not protect it correctly against multicast
> disconnects.

There's exactly 1 kernel client that uses multicast groups, and a patch was 
provided to migrate that client.

- Sean