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>
diff --git a/drivers/kvm/svm.c b/drivers/kvm/svm.c
index 442ca81..ef21804 100644
--- a/drivers/kvm/svm.c
+++ b/drivers/kvm/svm.c
@@ -1155,7 +1155,20 @@
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;
