Re: [PATCH 3/7] drm/i915: Always enable execlists on BDW for vgpu

Daniel Vetter
2015-09-02T08:07:01Z

On Thu, Aug 27, 2015 at 10:49:28AM +0800, Zhiyuan Lv wrote:
> Hi Daniel,
>
> On Wed, Aug 26, 2015 at 10:50:23AM +0200, Daniel Vetter wrote:
> > > > @@ -332,6 +332,12 @@ int i915_gem_context_init(struct drm_device
> > > > *dev)
> > > > if (WARN_ON(dev_priv->ring[RCS].default_context))
> > > > return 0;
> > > >
> > > > + if (intel_vgpu_active(dev)) {
> > > > + if (WARN_ON(HAS_LOGICAL_RING_CONTEXTS(dev) &&
> > > > + !i915.enable_execlist))
> > > > + return 0;
> > > > + }
> > > > +
> > >
> > > This looks fine to me. Maybe comment might be in place stating that
> > > support is not yet implemented, but could be.
> >
> > You should fail this instead so that i915.ko knows that the render side of
> > the gpu doesn't work. And maybe just DRM_INFO with a useful informational
> > notice?
>
> Thanks for the comments! Will change.
>
> >
> > Also same comment here: Don't we need to coordinate this a bit better with
> > the host?
>
> In host side, if driver is running in ring buffer mode, we will let GVT-g
> initialization fail, so that guest cannot set vgpu active. Would that be good
> enough? Thanks!

Yeah that seems sensible.
-Daniel
--
Daniel Vetter
Software Engineer, Intel Corporation