[Intel-xe] [PATCH 2/6] drm/xe/migrate: Update cpu page-table updates

[Matthew Brost]

On Wed, Mar 15, 2023 at 04:19:20PM +0100, Thomas Hellström wrote:
> 
> On 3/14/23 13:15, Matthew Auld wrote:
> > On Mon, 13 Mar 2023 at 20:46, Thomas Hellström
> > <thomas.hellstrom at linux.intel.com> wrote:
> > > Don't wait for GPU to be able to update page-tables using CPU. Putting
> > > ourselves to sleep may be more of a problem than using GPU for
> > > page-table updates. Also allow the vm to be NULL since the migrate
> > > kunit test uses NULL for vm.
> > > 
> > > Signed-off-by: Thomas Hellström <thomas.hellstrom at linux.intel.com>
> > Seems reasonable to me, but I'm not really familiar with the history here,
> > Reviewed-by: Matthew Auld <matthew.auld at intel.com>
> 
> Hmm, it turns out that this change uncovers a bug in xe_exec_basic igt
> (unless I misunderstand the syncobj semantics). I've posted a fix for that
> on igt-dev. With a little luck that also fixes the strange igt failures
> we've been seeing with deferred storage allocation on PVC.
> 

This change LGTM too and yea I've been aware of the issue with xe_exec_basic for
a while, after a quick look your fix does look correct. Will do a full review of
the xe_exec_basic fix today.

Matt 

> I won't merge this until the igt fix goes in.
> 
> /Thomas
> 
>