Commit 62b9abaa authored Dec 11, 2007 by Joerg Roedel Committed by Avi Kivity Jan 30, 2008

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 <joerg.roedel@amd.com>
Signed-off-by: Markus Rechberger <markus.rechberger@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

parent 722f6ecb

drivers/kvm/svm.c

+13 −0

Original line number	Diff line number	Diff line
		@@ -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;