KVM: X86: Introduce kvm_get_msr_feature()

Introduce kvm_get_msr_feature() to handle the msrs which are supported
by different vendors and sharing the same emulation logic.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Liran Alon <liran.alon@oracle.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>

1 files changed, 15 insertions, 3 deletions

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 54b4ed55945b..d97620eeb394 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1059,13 +1059,25 @@ static u32 msr_based_features[] = {
 
 static unsigned int num_msr_based_features;
 
+static int kvm_get_msr_feature(struct kvm_msr_entry *msr)
+{
+        switch (msr->index) {
+        default:
+                if (kvm_x86_ops->get_msr_feature(msr))
+                        return 1;
+        }
+        return 0;
+}
+
 static int do_get_msr_feature(struct kvm_vcpu *vcpu, unsigned index, u64 *data)
 {
         struct kvm_msr_entry msr;
+        int r;
 
         msr.index = index;
-        if (kvm_x86_ops->get_msr_feature(&msr))
-                return 1;
+        r = kvm_get_msr_feature(&msr);
+        if (r)
+                return r;
 
         *data = msr.data;
 
@@ -4522,7 +4534,7 @@ static void kvm_init_msr_list(void)
                 struct kvm_msr_entry msr;
 
                 msr.index = msr_based_features[i];
-                if (kvm_x86_ops->get_msr_feature(&msr))
+                if (kvm_get_msr_feature(&msr))
                         continue;
 
                 if (j < i)