From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753104AbZDVX0s (ORCPT ); Wed, 22 Apr 2009 19:26:48 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751749AbZDVX0j (ORCPT ); Wed, 22 Apr 2009 19:26:39 -0400 Received: from tomts10-srv.bellnexxia.net ([209.226.175.54]:54289 "EHLO tomts10-srv.bellnexxia.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751524AbZDVX0i (ORCPT ); Wed, 22 Apr 2009 19:26:38 -0400 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: ApoKAGdE70lMQW1W/2dsb2JhbACBT5VMuT+DdAY Date: Wed, 22 Apr 2009 19:26:36 -0400 From: Mathieu Desnoyers To: Alan Cox Cc: akpm@linux-foundation.org, Ingo Molnar , linux-kernel@vger.kernel.org, mark.langsdorf@amd.com, arekm@maven.pl, "H. Peter Anvin" , Andi Kleen , Avi Kivity Subject: Re: [patch 2/2] x86 amd fix cmpxchg read acquire barrier Message-ID: <20090422232636.GB22718@Krystal> References: <20090422201852.092307236@polymtl.ca> <20090422202453.829846363@polymtl.ca> <20090422215913.67c1298e@lxorguk.ukuu.org.uk> <20090422224749.GA22718@Krystal> <20090422235358.0e0cc7f3@lxorguk.ukuu.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline In-Reply-To: <20090422235358.0e0cc7f3@lxorguk.ukuu.org.uk> X-Editor: vi X-Info: http://krystal.dyndns.org:8080 X-Operating-System: Linux/2.6.21.3-grsec (i686) X-Uptime: 19:17:06 up 53 days, 19:43, 2 users, load average: 0.62, 0.60, 0.55 User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Alan Cox (alan@lxorguk.ukuu.org.uk) wrote: > > Good point. I should probably configure this as "nothing" unless > > > > #ifdef CONFIG_X86_64 > > #if (defined(CONFIG_GENERIC_CPU) || defined(CONFIG_MK8)) > > ... > > #endif > > #endif > > Is the erratum only present in 64bit mode ? > Hrm, from the info I gathered in the web pages linked in the patch header (refering to Google and Solaris), nothing said it was limited to 64bit mode. You are right. > Really this needs someone with knowledge of the erratum to characterise > it accurately and the workarounds. Yep, but all I can hear from AMD so far is... *crickets* The last revision of their errata I can find has been updated in February 2008, and does not talk about this issue. http://support.amd.com/us/Processor_TechDocs/25759.pdf Thanks, Mathieu -- Mathieu Desnoyers OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68