From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756097Ab1FVJwG (ORCPT ); Wed, 22 Jun 2011 05:52:06 -0400 Received: from smtp.eu.citrix.com ([62.200.22.115]:41207 "EHLO SMTP.EU.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752837Ab1FVJwE (ORCPT ); Wed, 22 Jun 2011 05:52:04 -0400 X-IronPort-AV: E=Sophos;i="4.65,405,1304294400"; d="scan'208";a="6419717" Subject: Re: [PATCH x86 kvm] Fix register corruption in pvclock_scale_delta From: Ian Campbell To: Avi Kivity CC: Zachary Amsden , kvm , Linux-kernel , Ulrich Obergfell In-Reply-To: <4E01B89C.7050704@redhat.com> References: <4DF97D6C.2080900@redhat.com> <4DFDEF2A.7050307@redhat.com> <1308735302.6920.172.camel@zakaz.uk.xensource.com> <4E01B89C.7050704@redhat.com> Content-Type: text/plain; charset="UTF-8" Organization: Citrix Systems, Inc. Date: Wed, 22 Jun 2011 10:52:01 +0100 Message-ID: <1308736321.6920.174.camel@zakaz.uk.xensource.com> MIME-Version: 1.0 X-Mailer: Evolution 2.32.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2011-06-22 at 10:40 +0100, Avi Kivity wrote: > On 06/22/2011 12:35 PM, Ian Campbell wrote: > > On Sun, 2011-06-19 at 15:44 +0300, Avi Kivity wrote: > > > On 06/16/2011 06:50 AM, Zachary Amsden wrote: > > > > The 128-bit multiply in pvclock.h was missing an output constraint for > > > > EDX which caused a register corruption to appear. > > > > Was there any particular symptom associated with corruption at that > > particular point or just general badness? > > > > Time went backwards and forwards as vcpus were migrated across cpus. Oops! > The problem was in the host, not the guest, so Xen should not be affected. Good to know, thanks! Ian.