From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Egger Subject: [PATCH] disable C1E for HVM guest Date: Thu, 12 Mar 2009 16:47:37 +0100 Message-ID: <200903121647.37350.Christoph.Egger@amd.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="Boundary-00=_Z6SuJTiileQDk/6" Return-path: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org --Boundary-00=_Z6SuJTiileQDk/6 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Content-Disposition: inline Hi, attached patch disables C1E in HVM guests. This also fixes a guest crash via #GP on cross-vendor migration. 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: Jochen Polster, Thomas M. McCoy, Giuliano Meroni Sitz: Dornach, Gemeinde Aschheim, Landkreis Muenchen Registergericht Muenchen, HRB Nr. 43632 --Boundary-00=_Z6SuJTiileQDk/6 Content-Type: text/x-diff; charset="us-ascii"; name="xen_hvm_c1e.diff" Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename="xen_hvm_c1e.diff" diff -r c9a35fb19e75 xen/arch/x86/hvm/hvm.c --- a/xen/arch/x86/hvm/hvm.c Thu Mar 12 15:08:08 2009 +0000 +++ b/xen/arch/x86/hvm/hvm.c Mon Mar 12 16:36:16 2009 +0100 @@ -1776,6 +1776,15 @@ int hvm_msr_read_intercept(struct cpu_us msr_content = var_range_base[index]; break; + case MSR_K8_ENABLE_C1E: + /* There's no point in letting the guest see C-States. + * Further, this AMD-only register may be accessed if this HVM guest + * has been migrated to an Intel host. This fixes a guest crash + * in this case. + */ + msr_content = 0; + break; + default: return hvm_funcs.msr_read_intercept(regs); } --Boundary-00=_Z6SuJTiileQDk/6 Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel --Boundary-00=_Z6SuJTiileQDk/6--