From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754808AbZHPJc6 (ORCPT ); Sun, 16 Aug 2009 05:32:58 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754267AbZHPJcz (ORCPT ); Sun, 16 Aug 2009 05:32:55 -0400 Received: from cavan.codon.org.uk ([93.93.128.6]:36454 "EHLO cavan.codon.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754751AbZHPJcx (ORCPT ); Sun, 16 Aug 2009 05:32:53 -0400 Date: Sun, 16 Aug 2009 10:32:51 +0100 From: Matthew Garrett To: Markus Trippelsdorf Cc: Zeev Tarantov , linux-kernel@vger.kernel.org Subject: Re: [BUG] [hwmon] linux 2.6.31-rc6 regression Message-ID: <20090816093251.GA1027@srcf.ucam.org> References: <12d7e64c0908150329k1bf123der18e74112c5b9cd97@mail.gmail.com> <20090816010303.GA9588@srcf.ucam.org> <20090816053735.GB1998@phenom2.trippelsdorf.de> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20090816053735.GB1998@phenom2.trippelsdorf.de> User-Agent: Mutt/1.5.18 (2008-05-17) X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: mjg59@cavan.codon.org.uk X-SA-Exim-Scanned: No (on cavan.codon.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Aug 16, 2009 at 07:37:35AM +0200, Markus Trippelsdorf wrote: > On Sun, Aug 16, 2009 at 02:03:03AM +0100, Matthew Garrett wrote: > > The hwmon driver is attempting to allocate a region that's also used by > > your ACPI firmware. There's no way to synchronise access between the > > kernel and the firmware, so allowing both is potentially racy - we've > > seen numerous cases where the combination results in the system > > incorrectly generating critical temperatuer shutdowns, for instance, > > when some other indexed access gets interpreted as the temperature or > > when the hwmon chip's state machine is confused. The failure of hwmon to > > bind is a feature here, not a bug. You can override it with > > acpi_enforce_resources=no on the kernel command line. > > But we don't introduce »features« that break hardware monitoring on > numerous machines in rc6 normally, IIRC. > If this so important and critical to you, than just add a »hyperstrict« > parameter to acpi_enforce_resources or make »lax« the default. It's not - 2.6.29 had this behaviour, and it got broken in 2.6.30. This restores the status quo. -- Matthew Garrett | mjg59@srcf.ucam.org