From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759784AbXFURwl (ORCPT ); Thu, 21 Jun 2007 13:52:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759640AbXFURw2 (ORCPT ); Thu, 21 Jun 2007 13:52:28 -0400 Received: from outbound-blu.frontbridge.com ([65.55.251.16]:11180 "EHLO outbound8-blu-R.bigfish.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758361AbXFURw1 (ORCPT ); Thu, 21 Jun 2007 13:52:27 -0400 X-BigFish: VP X-FB-SS: 0,0, X-MS-Exchange-Organization-Antispam-Report: OrigIP: 139.95.251.8;Service: EHS X-Server-Uuid: 519AC16A-9632-469E-B354-112C592D09E8 Date: Thu, 21 Jun 2007 19:51:22 +0200 From: "Joerg Roedel" To: "Avi Kivity" cc: kvm-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org Subject: [PATCH] SVM: reliably detect if SVM was disabled by BIOS Message-ID: <20070621175122.GE25896@amd.com> MIME-Version: 1.0 User-Agent: mutt-ng/devel-r804 (Linux) X-OriginalArrivalTime: 21 Jun 2007 17:51:32.0997 (UTC) FILETIME=[CDF00B50:01C7B42C] X-WSS-ID: 6A646548R0G895588-01-01 Content-Type: multipart/mixed; boundary=z6Eq5LdranGa6ru8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org --z6Eq5LdranGa6ru8 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: 7bit From: Joerg Roedel This patch adds an implementation to the svm is_disabled function to detect reliably if the BIOS disabled the SVM feature in the CPU. This fixes the issues with kernel panics when loading the kvm-amd module on machines where SVM is available but disabled. Signed-off-by: Joerg Roedel -- | AMD Saxony Limited Liability Company & Co. KG Operating | Wilschdorfer Landstr. 101, 01109 Dresden, Germany System | Register Court Dresden: HRA 4896 Research | General Partner authorized to represent: Center | AMD Saxony LLC (Wilmington, Delaware, US) | General Manager of AMD Saxony LLC: Dr. Hans-R. Deppe, Thomas McCoy --z6Eq5LdranGa6ru8 Content-Type: text/plain; charset=us-ascii Content-Disposition: attachment; filename=svm-detect-svm-disable.patch Content-Transfer-Encoding: 7bit diff --git a/drivers/kvm/svm.c b/drivers/kvm/svm.c index fa17d6d..54aa83a 100644 --- a/drivers/kvm/svm.c +++ b/drivers/kvm/svm.c @@ -1727,6 +1727,12 @@ static void svm_inject_page_fault(struct kvm_vcpu *vcpu, static int is_disabled(void) { + uint64_t vm_cr; + + rdmsrl(MSR_VM_CR, vm_cr); + if (vm_cr & (1 << SVM_VM_CR_SVM_DISABLE)) + return 1; + return 0; } diff --git a/drivers/kvm/svm.h b/drivers/kvm/svm.h index 5e93814..005a9c5 100644 --- a/drivers/kvm/svm.h +++ b/drivers/kvm/svm.h @@ -175,8 +175,11 @@ struct __attribute__ ((__packed__)) vmcb { #define SVM_CPUID_FUNC 0x8000000a #define MSR_EFER_SVME_MASK (1ULL << 12) +#define MSR_VM_CR 0xc0010114ULL #define MSR_VM_HSAVE_PA 0xc0010117ULL +#define SVM_VM_CR_SVM_DISABLE 4 + #define SVM_SELECTOR_S_SHIFT 4 #define SVM_SELECTOR_DPL_SHIFT 5 #define SVM_SELECTOR_P_SHIFT 7 --z6Eq5LdranGa6ru8--