KVM: VMX: Move MSR_IA32_FEAT_CTL.LOCKED check into "is valid" helper

Move the check on IA32_FEATURE_CONTROL being locked, i.e. read-only from
the guest, into the helper to check the overall validity of the incoming
value.  Opportunistically rename the helper to make it clear that it
returns a bool.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220607232353.3375324-3-seanjc@google.com

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 7be1fb5..fe5615f 100644 (file)
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -1850,8 +1850,8 @@ bool nested_vmx_allowed(struct kvm_vcpu *vcpu)
                                        FEAT_CTL_SGX_ENABLED             | \
                                        FEAT_CTL_LMCE_ENABLED)
 
-static inline bool vmx_feature_control_msr_valid(struct vcpu_vmx *vmx,
-                                                struct msr_data *msr)
+static inline bool is_vmx_feature_control_msr_valid(struct vcpu_vmx *vmx,
+                                                   struct msr_data *msr)
 {
        uint64_t valid_bits;
 
@@ -1862,6 +1862,10 @@ static inline bool vmx_feature_control_msr_valid(struct vcpu_vmx *vmx,
        WARN_ON_ONCE(vmx->msr_ia32_feature_control_valid_bits &
                     ~KVM_SUPPORTED_FEATURE_CONTROL);
 
+       if (!msr->host_initiated &&
+           (vmx->msr_ia32_feature_control & FEAT_CTL_LOCKED))
+               return false;
+
        if (msr->host_initiated)
                valid_bits = KVM_SUPPORTED_FEATURE_CONTROL;
        else
@@ -2266,10 +2270,9 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
                vcpu->arch.mcg_ext_ctl = data;
                break;
        case MSR_IA32_FEAT_CTL:
-               if (!vmx_feature_control_msr_valid(vmx, msr_info) ||
-                   (to_vmx(vcpu)->msr_ia32_feature_control &
-                    FEAT_CTL_LOCKED && !msr_info->host_initiated))
+               if (!is_vmx_feature_control_msr_valid(vmx, msr_info))
                        return 1;
+
                vmx->msr_ia32_feature_control = data;
                if (msr_info->host_initiated && data == 0)
                        vmx_leave_nested(vcpu);