From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Egger Subject: Re: [PATCH] [SVM]: Make 32bit legacy guests boot again Date: Mon, 29 Jun 2009 13:36:27 +0200 Message-ID: <200906291336.27591.Christoph.Egger@amd.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Content-Disposition: inline List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Keir Fraser Cc: "xen-devel@lists.xensource.com" List-Id: xen-devel@lists.xenproject.org Your changes broke the boot of 64bit guests. I see a triple fault now. Christoph On Monday 29 June 2009 11:17:39 Keir Fraser wrote: > I forgot to push. Should be there now. > > -- Keir > > On 29/06/2009 09:39, "Christoph Egger" wrote: > > Tnx. I will check as soon as it appears in the public staging tree. > > > > Christoph > > > > On Saturday 27 June 2009 11:35:20 Keir Fraser wrote: > >> Changeset 19856 is a cleaned up and streamlined version of this patch. > >> Please take a look. It also fixes a couple of largely theoretical > >> issues: * Should depend on EFER.LMA not EFER.LME > >> * Should handle the LMA 1->0 transition (i.e., return to legacy mode). > >> > >> -- Keir > >> > >> On 26/06/2009 16:19, "Christoph Egger" wrote: > >>> Hi! > >>> > >>> Attached patch fixes a bug introduced in c/s 19648. > >>> > >>> 32bit legacy guests have the sysenter/sysexit instructions available. > >>> Therefore, we have to disable intercepts for the sysenter MSRs or the > >>> guest stucks in an infinite loop of #GPs, otherwise. > >>> > >>> For guests in 64bit mode and 32bit compat mode, sysenter/sysexit > >>> instructions aren't available. The sysenter MSRs have to be intercepted > >>> to make the instruction emulation working. > >>> > >>> Attach patch first assumes the guest is in 32bit legacy mode and > >>> therefore disables the sysenter MSRs in construct_vmcb(). > >>> Access to the MSR_EFER is intercepted. When the guest enables longmode, > >>> then enable interception of the sysenter MSRs. > >>> > >>> Signed-off-by: Christoph Egger -- ---to satisfy European Law for business letters: Advanced Micro Devices GmbH Karl-Hammerschmidt-Str. 34, 85609 Dornach b. Muenchen Geschaeftsfuehrer: Thomas M. McCoy, Giuliano Meroni Sitz: Dornach, Gemeinde Aschheim, Landkreis Muenchen Registergericht Muenchen, HRB Nr. 43632