[Intel-gfx] [PATCH v2 1/4] drm/i915/gvt: reorder the shadow ppgtt update process by adding entry first

[Joonas Lahtinen]

On to, 2017-05-18 at 02:23 +0000, Zhang, Tina wrote:
> 
> > 
> > -----Original Message-----
> > From: intel-gvt-dev [mailto:intel-gvt-dev-bounces at lists.freedesktop.org] On
> > Behalf Of Joonas Lahtinen
> > Sent: Monday, May 15, 2017 6:50 PM
> > > > To: Zhang, Tina <tina.zhang at intel.com>; intel-gvt-dev at lists.freedesktop.org
> > Cc: intel-gfx at lists.freedesktop.org
> > Subject: Re: [Intel-gfx] [PATCH v2 1/4] drm/i915/gvt: reorder the shadow ppgtt
> > update process by adding entry first
> > 
> > On pe, 2017-05-12 at 17:37 +0800, Tina Zhang wrote:
> > > 
> > > Guest i915 driver may update the ppgtt table just before this workload
> > > is going to be submitted to the hardware by device model. This case
> > > wasn't handled well by device model before, due to the small time
> > > window between removing old ppgtt entry and adding the new one. Errors
> > > occur when the workload is executed by hardware during that small time
> > > window. This patch is to remove this time window by adding the new
> > > ppgtt entry first and then remove the old one.
> > > 
> > > > > > Signed-off-by: Tina Zhang <tina.zhang at intel.com>
> > 
> > This should be reviewed on the GVT mailing list, and this should include the
> > squashed hunk which exports the newly added capability.
> Thanks for the comments. I'm sorry I didn’t get it, here. Do you want
> me to remove this patch from this patch set?

It might be easier to merge if this is sent as two separate patch
series, because other gets merged through gvt tree and the other
directly to tip.

> Well, the reason this patch is here is because we met a GPU hang
> issue when guest i915 using full ppgtt. This is a blocking issue for
> enabling guest i915 full ppgtt functionality. This patch is to fix
> that issue. So, with this patch, the device model can have the
> capability to support guest i915 full ppgtt functionality. And the
> other patches in this patch set are used for guest to communicate
> with host whether the full ppgtt capability is supported.

Yes, but to help bisecting, the capability should be exported in the
same patch that implements the capability.

Regards, Joonas
-- 
Joonas Lahtinen
Open Source Technology Center
Intel Corporation