From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759327AbYDMPxV (ORCPT ); Sun, 13 Apr 2008 11:53:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754309AbYDMPxK (ORCPT ); Sun, 13 Apr 2008 11:53:10 -0400 Received: from pentafluge.infradead.org ([213.146.154.40]:44871 "EHLO pentafluge.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754111AbYDMPxJ (ORCPT ); Sun, 13 Apr 2008 11:53:09 -0400 Date: Sun, 13 Apr 2008 08:48:04 -0700 From: Arjan van de Ven To: Ingo Molnar Cc: "Rafael J. Wysocki" , Yinghai Lu , Andrew Morton , LKML , Pavel Machek , Thomas Gleixner , "H. Anvin" , Greg Kroah-Hartman Subject: Re: [rfc] hw resource debugging checks (was: Re: x86 git tree broken (bisected)) Message-ID: <20080413084804.2e511a3f@laptopd505.fenrus.org> In-Reply-To: <20080413075845.GJ20332@elte.hu> References: <200804102159.14563.rjw@sisk.pl> <20080410203800.GA14560@elte.hu> <200804110028.22290.rjw@sisk.pl> <200804112126.29455.rjw@sisk.pl> <20080413075845.GJ20332@elte.hu> Organization: Intel X-Mailer: Claws Mail 3.2.0 (GTK+ 2.12.5; i386-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-SRS-Rewrite: SMTP reverse-path rewritten from by pentafluge.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 13 Apr 2008 09:58:45 +0200 Ingo Molnar wrote: > > * Rafael J. Wysocki wrote: > > > > > btw., Xorg works fine here on a comparable AMD system - but i > > > > use a rather new distro (Fedora 8) which has Xorg 7.2. > > > > > > My system is an OpenSUSE 10.3 and it has Xorg 7.2 as well. > > > > > > I think the problem is somehow related to the Radeon. > > > > The bisection turned up commit > > ea1441bdf53692c3dc1fd2658addcf1205629661 "x86: use bus conf in NB > > conf fun1 to get bus range on, on 64-bit" as the one causing > > problems. > > thanks Rafael for bisecting this! > > This was a rather nasty problem - and i'm wondering what else we > could do to harden our hw resource management code. I'm wondering, is > there any particular reason why clearly broken resource setup is not > detected somewhere, automatically, and WARN_ON()-ed about? that would be very welcome, esp if kerneloops.org can pick them up. One thing we also need to do as Linux is get more conservative; (this isn't per se about this specific thing) With MCFG for example we learned over time "if it smells funny don't use it". That concept should be carried much further imo; for example on K8 you can compare the acpi table to the chipset for numa support, and if they don't match, we SHOULD ignore both entirely. The same is true all over; Linux tends to behave as "oh but we think we can make it work anyway", in general imo that's a mistake in the long term, at least for default configs. Because there will be cases where that will break, be it special bioses or next gens of chipsets. -- If you want to reach me at my work email, use arjan@linux.intel.com For development, discussion and tips for power savings, visit http://www.lesswatts.org