[openib-general] APM support in openib stack

[Sean Hefty]

> 1. does re-enabling Migration (as defined in vol1 of ib spec in 
> 17.2.8.1.4) work for you?
> (I mean after the 1st path failure, you do lap/apr packet transfer)

I believe that there's other issues that need to be fixed for this to fully 
work.  The ib_cm uses the primary_path specified during connection establishment 
to send CM MADs related to that connection.  If the primary_path fails and stays 
unavailable, future MADs (e.g. LAP) sent by the CM would also fail.  The CM 
records the alternate path, but currently doesn't do anything with it.  It needs 
to know when to switch to the alternate path for its MADs.

- Sean