kvm: x86: Don't modify MSR_PLATFORM_INFO on vCPU reset

If userspace has provided a different value for this MSR (e.g with the
turbo bits set), the userspace-provided value should survive a vCPU
reset. For backwards compatibility, MSR_PLATFORM_INFO is initialized
in kvm_arch_vcpu_setup.

Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Drew Schmitt <dasch@google.com>
Cc: Abhiroop Dabral <adabral@paloaltonetworks.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/x86.c

@@ -8658,6 +8658,7 @@ struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm,
 
 int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
 {
+	vcpu->arch.msr_platform_info = MSR_PLATFORM_INFO_CPUID_FAULT;
 	kvm_vcpu_mtrr_init(vcpu);
 	vcpu_load(vcpu);
 	kvm_vcpu_reset(vcpu, false);
@@ -8760,7 +8761,6 @@ void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
 		kvm_pmu_reset(vcpu);
 		vcpu->arch.smbase = 0x30000;
 
-		vcpu->arch.msr_platform_info = MSR_PLATFORM_INFO_CPUID_FAULT;
 		vcpu->arch.msr_misc_features_enables = 0;
 
 		vcpu->arch.xcr0 = XFEATURE_MASK_FP;