Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758978Ab2FFWBI (ORCPT ); Wed, 6 Jun 2012 18:01:08 -0400 Received: from terminus.zytor.com ([198.137.202.10]:43137 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752170Ab2FFWBG (ORCPT ); Wed, 6 Jun 2012 18:01:06 -0400 Message-ID: <4FCFD2EE.8060508@zytor.com> Date: Wed, 06 Jun 2012 15:00:14 -0700 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:12.0) Gecko/20120430 Thunderbird/12.0.1 MIME-Version: 1.0 To: Borislav Petkov CC: Konrad Rzeszutek Wilk , Jacob Shin , Andre Przywara , jeremy@goop.org, xen-devel@lists.xensource.com, LKML , Jan Beulich , Ingo Molnar , Thomas Gleixner , Andreas Herrmann , stable@vger.kernel.org.#.3.4+, Borislav Petkov Subject: Re: [PATCH 3/4] x86, AMD: Fix crash as Xen Dom0 on AMD Trinity systems References: <1338562358-28182-1-git-send-email-bp@amd64.org> <1338562358-28182-4-git-send-email-bp@amd64.org> In-Reply-To: <1338562358-28182-4-git-send-email-bp@amd64.org> X-Enigmail-Version: 1.4.1 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1647 Lines: 40 On 06/01/2012 07:52 AM, Borislav Petkov wrote: > From: Andre Przywara > > f7f286a910221 ("x86/amd: Re-enable CPU topology extensions in case BIOS > has disabled it") wrongfully added code which used the AMD-specific > {rd,wr}msr variants for no real reason. > > This caused boot panics on xen which wasn't initializing the > {rd,wr}msr_safe_regs pv_ops members properly. > > This, in turn, caused a heated discussion leading to us reviewing all > uses of the AMD-specific variants and removing them where unneeded > (almost everywhere except an obscure K8 BIOS fix, see 6b0f43ddfa358). > > Finally, this patch switches to the standard {rd,wr}msr*_safe* variants > which should've been used in the first place anyway and avoided unneeded > excitation with xen. > > Signed-off-by: Andre Przywara > Cc: Andreas Herrmann > Cc: stable@vger.kernel.org # 3.4+ > Link: > [Boris: correct and expand commit message] > Signed-off-by: Borislav Petkov Why -stable? I though we had agreed that we didn't have an active problem (unclean hack, yes, but not an active problem) in 3.4/3.5 as it currently sits? -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf. -- 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/