[openib-general] question regarding GRH flag in ib_ah_attr

[Sean Hefty]

Jason Gunthorpe wrote:
> How about this, how do you see this scenario:
> 
> 1) Client gets a DGID from 'someplace'
> 2) Client sends a SA query to resolve the DGID to a Path Record
> 3) Client configures a QP based on the Path Record
> 
> Now, the question I'm interested in is this:
>   During step #3 what test should the client apply to determine if a 
>   GRH should be used with the QP.

This is the scenario that I need to resolve.

What would happen if the GRH flag were always set?  Set only if the GID prefixes 
of the SGID/DGID were different?

- Sean