KVM: x86: Move nSVM CPUID 0x8000000A handling into common x86 code

Handle CPUID 0x8000000A in the main switch in __do_cpuid_func() and drop
->set_supported_cpuid() now that both VMX and SVM implementations are
empty.  Like leaf 0x14 (Intel PT) and leaf 0x8000001F (SEV), leaf
0x8000000A is is (obviously) vendor specific but can be queried in
common code while respecting SVM's wishes by querying kvm_cpu_cap_has().
Suggested-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/include/asm/kvm_host.h

@@ -1158,8 +1158,6 @@ struct kvm_x86_ops {
 
 	void (*set_tdp_cr3)(struct kvm_vcpu *vcpu, unsigned long cr3);
 
-	void (*set_supported_cpuid)(struct kvm_cpuid_entry2 *entry);
-
 	bool (*has_wbinvd_exit)(void);
 
 	u64 (*read_l1_tsc_offset)(struct kvm_vcpu *vcpu);

arch/x86/kvm/cpuid.c

@@ -741,6 +741,17 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function)
 		cpuid_entry_override(entry, CPUID_8000_0008_EBX);
 		break;
 	}
+	case 0x8000000A:
+		if (!kvm_cpu_cap_has(X86_FEATURE_SVM)) {
+			entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
+			break;
+		}
+		entry->eax = 1; /* SVM revision 1 */
+		entry->ebx = 8; /* Lets support 8 ASIDs in case we add proper
+				   ASID emulation to nested SVM */
+		entry->ecx = 0; /* Reserved */
+		cpuid_entry_override(entry, CPUID_8000_000A_EDX);
+		break;
 	case 0x80000019:
 		entry->ecx = entry->edx = 0;
 		break;
@@ -770,8 +781,6 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function)
 		break;
 	}
 
-	kvm_x86_ops->set_supported_cpuid(entry);
-
 	r = 0;
 
 out:

arch/x86/kvm/svm.c

@@ -6052,23 +6052,6 @@ static void svm_cpuid_update(struct kvm_vcpu *vcpu)
 					 APICV_INHIBIT_REASON_NESTED);
 }
 
-static void svm_set_supported_cpuid(struct kvm_cpuid_entry2 *entry)
-{
-	switch (entry->function) {
-	case 0x8000000A:
-		if (!kvm_cpu_cap_has(X86_FEATURE_SVM)) {
-			entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
-			break;
-		}
-		entry->eax = 1; /* SVM revision 1 */
-		entry->ebx = 8; /* Lets support 8 ASIDs in case we add proper
-				   ASID emulation to nested SVM */
-		entry->ecx = 0; /* Reserved */
-		cpuid_entry_override(entry, CPUID_8000_000A_EDX);
-		break;
-	}
-}
-
 static bool svm_has_wbinvd_exit(void)
 {
 	return true;
@@ -7428,8 +7411,6 @@ static struct kvm_x86_ops svm_x86_ops __ro_after_init = {
 
 	.cpuid_update = svm_cpuid_update,
 
-	.set_supported_cpuid = svm_set_supported_cpuid,
-
 	.has_wbinvd_exit = svm_has_wbinvd_exit,
 
 	.read_l1_tsc_offset = svm_read_l1_tsc_offset,

arch/x86/kvm/vmx/vmx.c

@@ -7102,10 +7102,6 @@ static void vmx_cpuid_update(struct kvm_vcpu *vcpu)
 	}
 }
 
-static void vmx_set_supported_cpuid(struct kvm_cpuid_entry2 *entry)
-{
-}
-
 static __init void vmx_set_cpu_caps(void)
 {
 	kvm_set_cpu_caps();
@@ -7919,7 +7915,6 @@ static struct kvm_x86_ops vmx_x86_ops __ro_after_init = {
 	.get_exit_info = vmx_get_exit_info,
 
 	.cpuid_update = vmx_cpuid_update,
-	.set_supported_cpuid = vmx_set_supported_cpuid,
 
 	.has_wbinvd_exit = cpu_has_vmx_wbinvd_exit,