From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Andre Przywara" Subject: [PATCH] hvm: Fix APIC-ID cpuid intercept Date: Wed, 06 Feb 2008 23:44:54 +0100 Message-ID: <47AA3866.8050606@amd.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary=------------090003040406060908050309 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: Keir.Fraser@cl.cam.ac.uk Cc: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org This is a multi-part message in MIME format. --------------090003040406060908050309 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 7bit Hi, the HVM CPUID intercept does not mask out the local APIC ID bits in CPUID Fn0000_0001, bits 24-31 in EBX. This results in inconsistent values of subsequent calls to cpuid on the same VCPU (delivering the value of the physical CPU), depending on the current scheduling. This for instance confuses Linux' NUMA code. The attached patch fixes this by replacing the physical APIC ID with the VCPU number, both in the VMX and SVM branches. Signed-off-by: Andre Przywara I hope this does not trigger any side effects... Regards, Andre -- Andre Przywara AMD-Operating System Research Center (OSRC), Dresden, Germany Tel: +49 351 277-84917 ----to satisfy European Law for business letters: AMD Saxony Limited Liability Company & Co. KG, Wilschdorfer Landstr. 101, 01109 Dresden, Germany Register Court Dresden: HRA 4896, General Partner authorized to represent: AMD Saxony LLC (Wilmington, Delaware, US) General Manager of AMD Saxony LLC: Dr. Hans-R. Deppe, Thomas McCoy --------------090003040406060908050309 Content-Type: text/plain; name=apic_id.patch Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename=apic_id.patch diff -r f8db1c6baad9 xen/arch/x86/hvm/svm/svm.c --- a/xen/arch/x86/hvm/svm/svm.c Tue Feb 05 23:27:12 2008 +0000 +++ b/xen/arch/x86/hvm/svm/svm.c Wed Feb 06 13:36:50 2008 +0100 @@ -1015,6 +1015,8 @@ static void svm_vmexit_do_cpuid(struct v __clear_bit(X86_FEATURE_HT & 31, &edx); ebx &= 0xFF00FFFF; /* clear the logical processor count when HTT=0 */ ebx |= 0x00010000; /* set to 1 just for precaution */ + ebx &= 0x00FFFFFF; /* clear the APIC ID */ + ebx |= (current->vcpu_id&0xFF)<<24; /* replace with vcpu_id */ break; case 0x80000001: diff -r f8db1c6baad9 xen/arch/x86/hvm/vmx/vmx.c --- a/xen/arch/x86/hvm/vmx/vmx.c Tue Feb 05 23:27:12 2008 +0000 +++ b/xen/arch/x86/hvm/vmx/vmx.c Wed Feb 06 13:36:50 2008 +0100 @@ -1311,6 +1311,8 @@ void vmx_cpuid_intercept( case 0x00000001: *ecx &= ~VMX_VCPU_CPUID_L1_ECX_RESERVED; *ebx &= NUM_THREADS_RESET_MASK; + *ebx &= 0x00FFFFFF; + *ebx |= (current->vcpu_id&0xFF)<<24; *ecx &= ~(bitmaskof(X86_FEATURE_VMXE) | bitmaskof(X86_FEATURE_EST) | bitmaskof(X86_FEATURE_TM2) | --------------090003040406060908050309 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 --------------090003040406060908050309--