From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Vetter Subject: Re: [PATCH] drm/i915: Don't deref pipe->cpu_transcoder in the hangcheck code Date: Fri, 9 Aug 2013 10:38:59 +0200 Message-ID: <20130809083859.GA21740@phenom.ffwll.local> References: <1375967526-12655-1-git-send-email-daniel.vetter@ffwll.ch> <20130808134423.GA29287@cantiga.alporthouse.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-ea0-f178.google.com (mail-ea0-f178.google.com [209.85.215.178]) by gabe.freedesktop.org (Postfix) with ESMTP id 7EC6AE5C37 for ; Fri, 9 Aug 2013 01:39:37 -0700 (PDT) Received: by mail-ea0-f178.google.com with SMTP id a15so1871129eae.23 for ; Fri, 09 Aug 2013 01:39:36 -0700 (PDT) Content-Disposition: inline In-Reply-To: <20130808134423.GA29287@cantiga.alporthouse.com> 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: Chris Wilson , Daniel Vetter , Intel Graphics Development , Paulo Zanoni , Damien Lespiau , Jani Nikula , stable@vger.kernel.org List-Id: intel-gfx@lists.freedesktop.org On Thu, Aug 08, 2013 at 02:44:23PM +0100, Chris Wilson wrote: > On Thu, Aug 08, 2013 at 03:12:06PM +0200, Daniel Vetter wrote: > > From: Chris Wilson > > > > If we get an error event really early in the driver setup sequence, > > which gen3 is especially prone to with various display GTT faults we > > Oops. So try to avoid this. > > > > Additionally with Haswell the transcoders are a separate bank of > > registers from the pipes (4 transcoders, 3 pipes). In event of an > > error, we want to be sure we have a complete and accurate picture of > > the machine state, so record all the transcoders in addition to all > > the active pipes. > > > > This regression has been introduced in > > > > commit 702e7a56af3780d8b3a717f698209bef44187bb0 > > Author: Paulo Zanoni > > Date: Tue Oct 23 18:29:59 2012 -0200 > > > > drm/i915: convert PIPECONF to use transcoder instead of pipe > > > > Based on the patch "drm/i915: Dump all transcoder registers on error" > > from Chris Wilson: > > > > v2: Rebase so that we don't try to be clever and try to figure out the > > cpu transcoder from hw state. That exercise should be done when we > > analyze the error state offline. > > > > The actual bugfix is to not call intel_pipe_to_cpu_transcoder in the > > error state capture code in case the pipes aren't fully set up yet. > > > > v3: Simplifiy the err->num_transcoders computation a bit. While at it > > make the error capture stuff save on systems without a display block. > > > > v4: Fix fail, spotted by Jani. > > > > v5: Completely new commit message, cc: stable. > > > > Cc: Paulo Zanoni > > Cc: Damien Lespiau > > Cc: Jani Nikula > > Cc: Chris Wilson > > Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=60021 > > Cc: stable@vger.kernel.org > > Signed-off-by: Daniel Vetter > > Lgtm. We may have to modify transcoders[] to be more dynamic in future, > but for now this works. > Reviewed-by: Chris Wilson Picked up for -fixes, thanks for the review. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch