From: Joerg Roedel Date: Tue, 11 Dec 2007 14:36:57 +0000 (+0100) Subject: KVM: SVM: support writing 0 to K8 performance counter control registers X-Git-Tag: v2.6.25-rc1~1138^2~38 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=62b9abaaf8423a3a38b938831b3b8431a6607ad8;p=linux-2.6 KVM: SVM: support writing 0 to K8 performance counter control registers This lets SVM ignore writes of the value 0 to the performance counter control registers. Thus enabling them will still fail in the guest, but a write of 0 which keeps them disabled is accepted. This is required to boot Windows Vista 64bit. [avi: avoid fall-thru in switch statement] Signed-off-by: Joerg Roedel Signed-off-by: Markus Rechberger Signed-off-by: Avi Kivity --- diff --git a/drivers/kvm/svm.c b/drivers/kvm/svm.c index 442ca818c5..ef21804a5c 100644 --- a/drivers/kvm/svm.c +++ b/drivers/kvm/svm.c @@ -1155,7 +1155,20 @@ static int svm_set_msr(struct kvm_vcpu *vcpu, unsigned ecx, u64 data) case MSR_IA32_SYSENTER_ESP: svm->vmcb->save.sysenter_esp = data; break; + case MSR_K7_EVNTSEL0: + case MSR_K7_EVNTSEL1: + case MSR_K7_EVNTSEL2: + case MSR_K7_EVNTSEL3: + /* + * only support writing 0 to the performance counters for now + * to make Windows happy. Should be replaced by a real + * performance counter emulation later. + */ + if (data != 0) + goto unhandled; + break; default: + unhandled: return kvm_set_msr_common(vcpu, ecx, data); } return 0;