Re: [PATCH] RDMA/srpt: Filter out AGN bits

Jason Gunthorpe
2019-08-19T16:17:02Z

On Mon, Aug 19, 2019 at 08:45:58AM -0700, Bart Van Assche wrote:
> On 8/19/19 8:17 AM, Jason Gunthorpe wrote:
> > On Mon, Aug 19, 2019 at 08:11:21AM -0700, Bart Van Assche wrote:
> > > Does uniqueness of the I/O controller GUID only matter in InfiniBand
> > > networks or does it also matter in other RDMA networks?
> > >
> > > How about using 0 as default value for the srpt_service_guid in RoCE
> > > networks?
> >
> > How does SRP connection management even work on RoCE?? The CM MADs
> > still carry a service_id? How do the sides exchange the service ID to
> > start the connection? Or is it ultimately overriden in the CM to use
> > an IP port based service ID?
>
> The ib_srpt kernel driver would have to set id_ext to a unique value if
> srpt_service_guid would be zero since the SRP initiator kernel driver uses
> the IOC GUID + id_ext + initiator_ext combination in its connection
> uniqueness check (srp_conn_unique()).

Sounds like you should just generate something random for RDMA/CM mode ?

Still a bit confused how this is usable though if the initiating side
needs the service ID?

Jason