KVM: x86: Turbo bits in MSR_PLATFORM_INFO

dasch-1 · bonzini · commit d84f1cff9028 · 2018-09-20T00:51:46.000+02:00
Allow userspace to set turbo bits in MSR_PLATFORM_INFO. Previously, only
the CPUID faulting bit was settable. But now any bit in
MSR_PLATFORM_INFO would be settable. This can be used, for example, to
convey frequency information about the platform on which the guest is
running.

Signed-off-by: Drew Schmitt &lt;dasch@google.com&gt;
Signed-off-by: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
@@ -2537,7 +2537,6 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
 		break;
 	case MSR_PLATFORM_INFO:
 		if (!msr_info->host_initiated ||
-		    data & ~MSR_PLATFORM_INFO_CPUID_FAULT ||
 		    (!(data & MSR_PLATFORM_INFO_CPUID_FAULT) &&
 		     cpuid_fault_enabled(vcpu)))
 			return 1;
