Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761402AbXIJVF2 (ORCPT ); Mon, 10 Sep 2007 17:05:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753735AbXIJVFS (ORCPT ); Mon, 10 Sep 2007 17:05:18 -0400 Received: from mga02.intel.com ([134.134.136.20]:25480 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752169AbXIJVFR convert rfc822-to-8bit (ORCPT ); Mon, 10 Sep 2007 17:05:17 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.20,233,1186383600"; d="scan'208";a="292062343" X-MimeOLE: Produced By Microsoft Exchange V6.5 Content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT Subject: RE: [patch] enable userspace cpu core voltage control withacpi-cpufreq Date: Mon, 10 Sep 2007 14:04:05 -0700 Message-ID: <653FFBB4508B9042B5D43DC9E18836F5015DB050@scsmsx415.amr.corp.intel.com> In-Reply-To: <20070903152457.GC21586@redhat.com> X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: [patch] enable userspace cpu core voltage control withacpi-cpufreq Thread-Index: AcfuPwNAKmp9HOwORfuMDSYCMW2ALAFrokLA References: <200709021441.l82EfWCe022642@mail.mc.o2online.de> <20070903152457.GC21586@redhat.com> From: "Pallipadi, Venkatesh" To: "Dave Jones" , "Andi Kleen" Cc: , X-OriginalArrivalTime: 10 Sep 2007 21:05:14.0586 (UTC) FILETIME=[48678BA0:01C7F3EE] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1941 Lines: 46 >-----Original Message----- >From: linux-kernel-owner@vger.kernel.org >[mailto:linux-kernel-owner@vger.kernel.org] On Behalf Of Dave Jones >Sent: Monday, September 03, 2007 8:25 AM >To: Andi Kleen >Cc: colin.michael@o2online.de; linux-kernel@vger.kernel.org >Subject: Re: [patch] enable userspace cpu core voltage control >withacpi-cpufreq > >On Mon, Sep 03, 2007 at 12:56:13PM +0200, Andi Kleen wrote: > > writes: > > > > > i want to make a patch known that provides a userspace >interface to control the core voltage of a computer processor(s). > > > > That would be essentially linux supported undervolting which > > for stability is as bad as overclocking. The problem is that > > such games tend to generate weird kernel crashes and then > > chew up development issues when kernel hackers have to chase > > ghost bugs. I don't think we should support it. Developer > > time is too precious. > >Seconded. Exactly the same reasons I've refused to merge patches >into cpufreq to allow arbitrary tables to override BIOS tables. >Or patches to remove boundary checks. Even when correctly >implemented, this stuff can be fragile as hell, so introducing >more things that cast doubt over its stability isn't something >I'm keen on at all. > And acpi-cpufreq does not seem to be the place to be doing this. I would say it should be a new driver or go into speedstep-centrino which has similar user defined freq voltage values. Ideally a standalone driver so that users do not get confused with single driver working in different modes and distributors can choose not to ship it in case where they do not like the driver tainting the kernel. Thanks, Venki - 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/