@@ -2915,7 +2915,16 @@ static int svm_set_msr(struct kvm_vcpu *
svm_disable_lbrv(vcpu);
break;
case MSR_VM_HSAVE_PA:
- svm->nested.hsave_msr = data;
+ /*
+ * Old kernels did not validate the value written to
+ * MSR_VM_HSAVE_PA. Allow KVM_SET_MSR to set an invalid
+ * value to allow live migrating buggy or malicious guests
+ * originating from those kernels.
+ */
+ if (!msr->host_initiated && !page_address_valid(vcpu, data))
+ return 1;
+
+ svm->nested.hsave_msr = data & PAGE_MASK;
break;
case MSR_VM_CR:
return svm_set_vm_cr(vcpu, data);