[openib-general] [RFC] CM reject handling and redirection

[Sean Hefty]

Roland Dreier wrote:
> Code 25 (port redirection only) raises a separate issue that I think
> is orthogonal to REJ handling.  The CM spec always allows the CM to
> run on a different port from the destination of a connection so if we
> want to implement the whole spec we do need a way for the consumer to
> specify a primary and alternate path for the connection itself as well
> as a CM path.

It looks like one way to handle this is to add a new field to struct 
ib_cm_req_param: struct ib_sa_path_rec *cm_path.  A user could easily 
set this to the same path record referenced by the *primary_path field. 
  This would only be a small change to existing users.

I'm still not sure how to handle a failed path between the CMs.  And 
even if you could detect a failed path, recovering from it is difficult 
without violating the REQ max_cm_retries.  Is anyone planning on using APM?

- Sean