From mboxrd@z Thu Jan  1 00:00:00 1970
From: Daniel Vetter <daniel@ffwll.ch>
Subject: Re: [PATCH] drm/i915: Gracefully handle obj not bound
 to GGTT in is_pin_display
Date: Thu, 15 May 2014 15:45:30 +0200
Message-ID: <20140515134530.GT8790@phenom.ffwll.local>
References: <1396462861-16396-1-git-send-email-oscar.mateo@intel.com>
 <20140403093450.GC7225@phenom.ffwll.local>
 <92648605EABDA246B775AAB04C95A7A3012ED004@IRSMSX103.ger.corp.intel.com>
 <20140512161118.GH25056@phenom.ffwll.local>
 <20140512161453.GI25056@phenom.ffwll.local>
 <92648605EABDA246B775AAB04C95A7A3012EE985@IRSMSX103.ger.corp.intel.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Return-path: <intel-gfx-bounces@lists.freedesktop.org>
Received: from mail-wg0-f46.google.com (mail-wg0-f46.google.com [74.125.82.46])
 by gabe.freedesktop.org (Postfix) with ESMTP id 7609289F3B
 for <intel-gfx@lists.freedesktop.org>; Thu, 15 May 2014 06:45:35 -0700 (PDT)
Received: by mail-wg0-f46.google.com with SMTP id n12so3528427wgh.5
 for <intel-gfx@lists.freedesktop.org>; Thu, 15 May 2014 06:45:34 -0700 (PDT)
Content-Disposition: inline
In-Reply-To: <92648605EABDA246B775AAB04C95A7A3012EE985@IRSMSX103.ger.corp.intel.com>
List-Unsubscribe: <http://lists.freedesktop.org/mailman/options/intel-gfx>,
 <mailto:intel-gfx-request@lists.freedesktop.org?subject=unsubscribe>
List-Archive: <http://lists.freedesktop.org/archives/intel-gfx>
List-Post: <mailto:intel-gfx@lists.freedesktop.org>
List-Help: <mailto:intel-gfx-request@lists.freedesktop.org?subject=help>
List-Subscribe: <http://lists.freedesktop.org/mailman/listinfo/intel-gfx>,
 <mailto:intel-gfx-request@lists.freedesktop.org?subject=subscribe>
Errors-To: intel-gfx-bounces@lists.freedesktop.org
Sender: "Intel-gfx" <intel-gfx-bounces@lists.freedesktop.org>
To: "Mateo Lozano, Oscar" <oscar.mateo@intel.com>
Cc: "intel-gfx@lists.freedesktop.org" <intel-gfx@lists.freedesktop.org>
List-Id: intel-gfx@lists.freedesktop.org

On Thu, May 15, 2014 at 01:14:54PM +0000, Mateo Lozano, Oscar wrote:
> > > But looking at the code a better way should be:
> > > 1. Create new bo, wrap it in a kms fb.
> > > 2. Slap busy load onto that bo, e.g. reapeatedly fill it with the blitter.
> > > 3. Enable evil interruptor (igt_fork_signal_helper).
> > > 4. Submit pageflip
> > >
> > > -> Boom since the set_cache_level will block, get interrupted and exit
> > > early with -EINTR.
> > >
> > > Given sufficient overkill in 2. this should be 100% reliable to reproduce.
> 
> As soon as I execbuffer to the bo, it gets a vma for the GGTT vm:
> 
> 	vm = ctx->vm;
> 	if (!USES_FULL_PPGTT(dev))
> 		vm = &dev_priv->gtt.base;
> 
> 	...
> 
> 	/* Look up object handles */
> 	ret = eb_lookup_vmas(eb, exec, args, vm, file);
> 	if (ret)
> 		goto err;
> 
> And then it becomes impossible to reproduce the problem :(
> Is there any other trick to make set_cache_level fail?

i915.ppgtt=2 should still make this blow up. The bug kinda doesn't exist
without full ppgtt I think ...
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch