From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Wilson Subject: Re: [PATCH] drm/i915: dump even more into the error_state Date: Wed, 01 Feb 2012 21:39:15 +0000 Message-ID: References: <1328131605-20174-1-git-send-email-daniel.vetter@ffwll.ch> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mga03.intel.com (mga03.intel.com [143.182.124.21]) by gabe.freedesktop.org (Postfix) with ESMTP id 1EC14A0C9D for ; Wed, 1 Feb 2012 13:39:22 -0800 (PST) In-Reply-To: <1328131605-20174-1-git-send-email-daniel.vetter@ffwll.ch> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org Errors-To: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org To: Intel Graphics Development Cc: Daniel Vetter List-Id: intel-gfx@lists.freedesktop.org On Wed, 1 Feb 2012 22:26:45 +0100, Daniel Vetter wrote: > Chris Wilson and me have again stared at funny error states and it's > been pretty clear from the start that something was seriously amiss. > The seqnos last seen by the cpu were a few hundred behind those that > the gpu could have possibly emitted last before it died ... > > Chris now tracked it down (hopefully, definit verdict's still out), > but in hindsight we'd have found the bug by simply dumping the cpu > side tracking of the ring head and tail registers. > > Fix this and prevent an identical time-waster in the future. > > Because the hangs always involved semaphores in one way or another, > we've tried to dump the mbox registers, but couldn't find any > inconsistencies. Still, dump them too. > > Signed-Off-by: Daniel Vetter Reviewed-and-wanted-by: Chris Wilson -Chris -- Chris Wilson, Intel Open Source Technology Centre