RE: [PATCH v2 10/17] IB/Verbs: Adopt management helpers for IB helpers

["Steve Wise" <swise@opengridcomputing.com>]

> -----Original Message-----
> From: Jason Gunthorpe [mailto:jgunthorpe@obsidianresearch.com]
> Sent: Tuesday, April 07, 2015 3:13 PM
> To: Michael Wang
> Cc: Roland Dreier; Sean Hefty; linux-rdma@vger.kernel.org; linux-kernel@vger.kernel.org; linux-nfs@vger.kernel.org;
> netdev@vger.kernel.org; Hal Rosenstock; Tom Tucker; Steve Wise; Hoang-Nam Nguyen; Christoph Raisch; Mike Marciniszyn; Eli Cohen;
> Faisal Latif; Upinder Malhi; Trond Myklebust; J. Bruce Fields; David S. Miller; Ira Weiny; PJ Waskiewicz; Tatyana Nikolova; Or
Gerlitz; Jack
> Morgenstein; Haggai Eran; Ilya Nelkenbaum; Yann Droneaud; Bart Van Assche; Shachar Raindel; Sagi Grimberg; Devesh Sharma; Matan
> Barak; Moni Shoua; Jiri Kosina; Selvin Xavier; Mitesh Ahuja; Li RongQing; Rasmus Villemoes; Alex Estrin; Doug Ledford; Eric
Dumazet; Erez
> Shitrit; Tom Gundersen; Chuck Lever
> Subject: Re: [PATCH v2 10/17] IB/Verbs: Adopt management helpers for IB helpers
> 
> On Tue, Apr 07, 2015 at 02:35:22PM +0200, Michael Wang wrote:
> > index f704254..4e61104 100644
> > +++ b/drivers/infiniband/core/sa_query.c
> > @@ -540,7 +540,7 @@ int ib_init_ah_from_path(struct ib_device *device, u8 port_num,
> >  	ah_attr->port_num = port_num;
> >  	ah_attr->static_rate = rec->rate;
> >
> > -	force_grh = rdma_port_get_link_layer(device, port_num) == IB_LINK_LAYER_ETHERNET;
> > +	force_grh = !rdma_transport_ib(device, port_num);
> 
> Maybe these tests should be called cap_mandatory_grh - but I'm not
> really sure how iWarp uses the GRH fields in the AH...
> 

iWARP runs on top of TCP...this SA code is all IB-specific.  The reason it was checking for ETHERNET, I think, is for RoCE.    So
this change is totally incorrect,  I think,  because RoCE is an IB transport, but it runs on ETHERNET.

Steve.