From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755688Ab2E3Ond (ORCPT ); Wed, 30 May 2012 10:43:33 -0400 Received: from terminus.zytor.com ([198.137.202.10]:38925 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752998Ab2E3Ona (ORCPT ); Wed, 30 May 2012 10:43:30 -0400 Message-ID: <4FC631F0.9080109@zytor.com> Date: Wed, 30 May 2012 07:42:56 -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: Jan Beulich CC: Andre Przywara , Jacob Shin , mingo@elte.hu, jeremy@goop.org, tglx@linutronix.de, xen-devel@lists.xensource.com, konrad.wilk@oracle.com, linux-kernel@vger.kernel.org Subject: Re: [Xen-devel] [PATCH] x86/amd: fix crash as Xen Dom0 on AMD Trinity systems References: <1338383402-3838-1-git-send-email-andre.przywara@amd.com> <4FC63DAF0200007800086DC5@nat28.tlf.novell.com> <4FC62888.9010407@amd.com> <4FC649790200007800086E51@nat28.tlf.novell.com> In-Reply-To: <4FC649790200007800086E51@nat28.tlf.novell.com> X-Enigmail-Version: 1.4.1 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 05/30/2012 07:23 AM, Jan Beulich wrote: > > I see - the Xen code blindly overwrites pv_cpu_ops, despite not > having initialized all members. That's an obvious oversight of the > patch that introduced the _regs variants. > > Plus having secondary instances of things like rdmsrl_amd_safe() > in asm/paravirt.h seems pretty strange an approach (which was > why initially I didn't spot how a crash could happen there) - only > the lowest level functions should get re-implemented here. > This kinds of things are part of why Xen makes me want to cry regularly. -hpa