From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753811AbZHTVod (ORCPT ); Thu, 20 Aug 2009 17:44:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753439AbZHTVoc (ORCPT ); Thu, 20 Aug 2009 17:44:32 -0400 Received: from terminus.zytor.com ([198.137.202.10]:34800 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752598AbZHTVob (ORCPT ); Thu, 20 Aug 2009 17:44:31 -0400 Message-ID: <4A8DC349.5060508@zytor.com> Date: Thu, 20 Aug 2009 14:42:33 -0700 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1b3pre) Gecko/20090513 Fedora/3.0-2.3.beta2.fc11 Thunderbird/3.0b2 MIME-Version: 1.0 To: Suresh Siddha CC: Alex Chiang , Andi Kleen , "mingo@redhat.com" , "tglx@linutronix.de" , "x86@kernel.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] x86: add /proc/cpuinfo/physical id quirks References: <20090814163618.GQ7185@ldl.fc.hp.com> <1250276831.3077.17.camel@sbs-t61.sc.intel.com> <20090814192730.GA6431@ldl.fc.hp.com> <1250279799.3077.41.camel@sbs-t61.sc.intel.com> <20090819210251.GD13061@ldl.fc.hp.com> <1250794594.2754.10.camel@sbs-t61.sc.intel.com> <20090820205425.GF13061@ldl.fc.hp.com> <20090820210342.GC29994@basil.fritz.box> <20090820212024.GG13061@ldl.fc.hp.com> <1250803577.2754.30.camel@sbs-t61.sc.intel.com> In-Reply-To: <1250803577.2754.30.camel@sbs-t61.sc.intel.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 08/20/2009 02:26 PM, Suresh Siddha wrote: > On Thu, 2009-08-20 at 14:20 -0700, Alex Chiang wrote: >> It turns out I need to rework my patch anyway because I need to >> think about the case where a user disables some cores in the >> BIOS, in which case my (fragile) table selection scheme falls >> apart. > > These are the sort of reasons why we want topology detection to be > completely based on what cpuid instruction says and nothing else. > I agree... if this ID is used for topology detection, we shouldn't replace it arbitrarily with information from BIOS just to hope that it matches the motherboard stencil. *Furthermore*, there is no reason why motherboard stencilAs are purely numeric... consider the rather obvious case of two rows of four CPUs; they may have CPU slots labelled A1, A2, A3, A4, B1, B2, B3, B4. It might very well be the right thing to support arbitrary strings for platforms we recognize. As such I think we should have a socket name field in both /proc/cpuinfo and sysfs. -hpa