Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754366AbZLMVc0 (ORCPT ); Sun, 13 Dec 2009 16:32:26 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753446AbZLMVcZ (ORCPT ); Sun, 13 Dec 2009 16:32:25 -0500 Received: from moutng.kundenserver.de ([212.227.17.9]:49222 "HELO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1753352AbZLMVcY (ORCPT ); Sun, 13 Dec 2009 16:32:24 -0500 From: Arnd Bergmann To: Daniel Vetter Subject: Re: [BISECTED] drm: random hang since 620f378 "drm: prune modes when ..." Date: Sun, 13 Dec 2009 21:31:07 +0000 User-Agent: KMail/1.12.2 (Linux/2.6.31-rc8-00047-g0430296; KDE/4.3.2; x86_64; ; ) Cc: Dave Airlie , Adam Jackson , linux-kernel@vger.kernel.org, dri-devel@lists.sourceforge.net, keithp@keithp.com, eric@anholt.net, jbarnes@virtuousgeek.org, Daniel Vetter References: <200912071830.14697.arnd@arndb.de> <200912131230.25781.arnd@arndb.de> <20091213200017.GA3522@viiv.ffwll.ch> In-Reply-To: <20091213200017.GA3522@viiv.ffwll.ch> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <200912132131.07100.arnd@arndb.de> X-Provags-ID: V01U2FsdGVkX19B5A0YqSZCTUnbFutUd3S0pzHsoZOoj7E8Hli mxk0BcCG//I0zqCOdMPCDblumABolUQpzenPCgLo4sOfTFPp/b 2vL0UmtqgNqbheJzFbWgA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1572 Lines: 31 On Sunday 13 December 2009 20:00:18 Daniel Vetter wrote: > On Sun, Dec 13, 2009 at 12:30:25PM +0000, Arnd Bergmann wrote: > > And now it's obvious that my computer hates me. 12 hours of uptime, one reboot > > to check the old other version is broken, it crashes. I reboot into the > > good version, send out the above email and the next minute it crashes again. > > c05422d52ee6b is not the culprit. Sorry Daniel for blaming your patch. > > No problem. Looks like your hunting a pretty ugly Heisenbug. There's quite > a interesting blog post by Paul McKenney, esp. the solution to "Quick Quiz 1" > might be usefull in your case: > > http://paulmck.livejournal.com/14639.html Thanks! In fact I've actually read that post on the kernel planet and decided to do basically a linear search through the i915 patches merged into 2.6.32. The current result is 67cf781bea5 "drm/i915: Make the downclocking debug code be under DRM_DEBUG not DRM_ERROR." is known bad, while 043029655 "drm/i915: Support IGD EOS" is probably good, pointing to Jesses 652c393a33 "drm/i915: add dynamic clock frequency control" as the next best guess. Unfortunately, that is a rather large change that is not easy to revert on current kernels. I'll keep running my machine on the 043029655 level and tell you if it keeps working a few more days. Arnd -- 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/