Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754758Ab0HXJzi (ORCPT ); Tue, 24 Aug 2010 05:55:38 -0400 Received: from silver.sucs.swan.ac.uk ([137.44.10.1]:43400 "EHLO silver.sucs.swan.ac.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754570Ab0HXJzg (ORCPT ); Tue, 24 Aug 2010 05:55:36 -0400 Date: Tue, 24 Aug 2010 10:55:35 +0100 From: Sitsofe Wheeler To: Chris Wilson Cc: LKML , dri-devel@lists.freedesktop.org Subject: Re: [REGRESSION, BISECTED, i915]: Periodic stalls with 2.6.36-rc2 Message-ID: <20100824095535.GA14020@sucs.org> References: <20100823233551.GA31920@sucs.org> <89kc63$hrmse5@fmsmga002.fm.intel.com> <20100824075741.GA11000@sucs.org> <8u3s8d$jcg467@orsmga001.jf.intel.com> <20100824084902.GA27569@sucs.org> <89kc63$hrqoho@fmsmga002.fm.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <89kc63$hrqoho@fmsmga002.fm.intel.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1845 Lines: 44 On Tue, Aug 24, 2010 at 10:00:47AM +0100, Chris Wilson wrote: > > I was hoping that git would be more intelligent than that. Is there a > way to simply bisect down one side of a merge? Seemingly not... > The slow boot is probably fixed by 4936a3b90d79dd8775c6ac23c2cf2dcebe29abde. > A trivial patch you can apply on each step is: Thanks that patch got it booting at normal speeds. Bisecting has now narrowed the flickering/corruption with a newer X userspace down to this: commit 9d0498a2bf7455159b317f19531a3e5db2ecc9c4 Author: Jesse Barnes Date: Wed Aug 18 13:20:54 2010 -0700 drm/i915: wait for actual vblank, not just 20ms Waiting for a hard coded 20ms isn't always enough to make sure a vblank period has actually occurred, so add code to make sure we really have passed through a vblank period (or that the pipe is off when disabling). This prevents problems with mode setting and link training, and seems to fix a bug like https://bugs.freedesktop.org/show_bug.cgi?id=29278, but on an HP 8440p instead. Hopefully also fixes https://bugs.freedesktop.org/show_bug.cgi?id=29141. Signed-off-by: Jesse Barnes Signed-off-by: Eric Anholt Reverting the above against HEAD seems to have fixed the misdetection of displays and hangcheck warnings don't appear (although plenty of FIFO warnings still). I notice that this commit also seemed to be the cause of problems for Ivan and Pekka in http://lkml.org/lkml/2010/8/23/452 ... -- Sitsofe | http://sucs.org/~sits/ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/