From mboxrd@z Thu Jan  1 00:00:00 1970
From: Daniel Vetter <daniel@ffwll.ch>
Subject: Re: [PATCH] drm/i915: Remove bogus test for a present
 execbuffer
Date: Mon, 19 Nov 2012 17:53:32 +0100
Message-ID: <20121119165332.GC5854@phenom.ffwll.local>
References: <1353339042-23076-1-git-send-email-chris@chris-wilson.co.uk>
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To: Eric Anholt <eric@anholt.net>
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On Mon, Nov 19, 2012 at 08:42:59AM -0800, Eric Anholt wrote:
> Chris Wilson <chris@chris-wilson.co.uk> writes:
> 
> > The intention of checking obj->gtt_offset!=0 is to verify that the
> > target object was listed in the execbuffer and had been bound into the
> > GTT. This is guarranteed by the earlier rearrangement to split the
> > execbuffer operation into reserve and relocation phases and then
> > verified by the check that the target handle had been processed during
> > the reservation phase.
> >
> > However, the actual checking of obj->gtt_offset==0 is bogus as we can
> > indeed reference an object at offset 0. For instance, the framebuffer
> > installed by the BIOS often resides at offset 0 - causing EINVAL as we
> > legimately try to render using the stolen fb.
> 
> We've never triggered this check in practice, as far as I know, so I'm
> happy to see it go.
> 
> Reviewed-by: Eric Anholt <eric@anholt.net>

Queued for -next, thanks for the patch.
-Daniel

-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch