Re: [PATCH] drm/i915: disable cpu relocs on ilk and earlier

From: Chris Wilson <chris@chris-wilson.co.uk>
To: Intel Graphics Development <intel-gfx@lists.freedesktop.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>, stable@vger.kernel.org
Subject: Re: [PATCH] drm/i915: disable cpu relocs on ilk and earlier
Date: Wed, 10 Oct 2012 10:13:03 +0100	[thread overview]
Message-ID: <b94cdc$6tbe2e@fmsmga001.fm.intel.com> (raw)
In-Reply-To: <1349856400-16502-1-git-send-email-daniel.vetter@ffwll.ch>

On Wed, 10 Oct 2012 10:06:40 +0200, Daniel Vetter <daniel.vetter@ffwll.ch> wrote:
> They seem to be implicated in render corruptions. And up to now no one
> really seems to understand the issue, so let's just disable them for
> now. Most of the machines exhibiting this issue have only a 128 gtt
> mmio window, so increased pressure on the mappable part (and so higher
> chance for cpu relocs) seems to be the key.
> 
> Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=852210
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=55112
> Cc: Dave Airlie <airlied@gmail.com>
> Cc: stable@vger.kernel.org
> [Note for stable, there's a minor conflict in the context since we've
> tuned cpu relocs on gen6+ a bit in 3.7.]
> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

My only query is that the fdo reporter said that "kernel 3.6 + drm-next"
didn't trigger the error. So I'd like some confirmation that this patch
is indeed needed for 3.7, but meh. (If only because that might give some
insight as to what the root cause is.)

Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre