Subject: RE: [rdma-rc PATCH 2/2] iw_cxgb4: cq/qp mask depends on bar2 pages in a host page

From: "Steve Wise" <[email-masked]>
Date: Thu, 14 Feb 2019 11:54:16 -0600

> -----Original Message-----
> From: [email-masked] <linux-rdma-
> [email-masked]> On Behalf Of Raju Rangoju
> Sent: Thursday, February 14, 2019 11:28 AM
> To: Jason Gunthorpe <[email-masked]>
> Cc: [email-masked]; [email-masked];
> [email-masked]; [email-masked]
> Subject: Re: [rdma-rc PATCH 2/2] iw_cxgb4: cq/qp mask depends on bar2
> pages in a host page
> 
> On Thursday, February 02/14/19, 2019 at 15:41:34 +0000, Jason Gunthorpe
> wrote:
> > On Thu, Feb 14, 2019 at 05:40:54PM +0530, Raju Rangoju wrote:
> > > Adjust the cq/qp mask based on no.of bar2 pages in a host page.
> > >
> > > For user-mode rdma, the granularity of the BAR2 memory mapped
> > > to a user rdma process during queue allocation must be based
> > > on the host page size. The lld attributes udb_density and
> > > ucq_density are used to figure out how many sge contexts are
> > > in a bar2 page. So the rdev->qpmask and rdev->cqmask in
> > > iw_cxgb4 need to now be adjusted based on how many sge bar2
> > > pages are in a host page.
> >
> > Why is this rc? Do certain arches fail to work or something?
> >
> 
> Yes, this series fixes a regression that was introduced by commit
> 2391b0030e (v5.0-rc1~129^2~272)
> 
> > Jason

Rdma over cxgb4 on arches with a non-4K page size are busted w/o this fix.
That was the motivation for -rc.