KVM: x86: Handle RDTSCP CPUID adjustment in VMX code

Move the clearing of the RDTSCP CPUID bit into VMX, which has a separate
VMCS control to enable RDTSCP in non-root, to eliminate an instance of
the undesirable "unsigned f_* = *_supported ? F(*) : 0" pattern in the
common CPUID handling code.  Drop ->rdtscp_supported() since CPUID
adjustment was the last remaining user.

No functional change intended.
Reviewed-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/cpuid.c

@@ -416,7 +416,6 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function)
 	unsigned f_gbpages = 0;
 	unsigned f_lm = 0;
 #endif
-	unsigned f_rdtscp = kvm_x86_ops->rdtscp_supported() ? F(RDTSCP) : 0;
 	unsigned f_xsaves = kvm_x86_ops->xsaves_supported() ? F(XSAVES) : 0;
 	unsigned f_intel_pt = kvm_x86_ops->pt_supported() ? F(INTEL_PT) : 0;
 
@@ -438,7 +437,7 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function)
 		F(MTRR) | F(PGE) | F(MCA) | F(CMOV) |
 		F(PAT) | F(PSE36) | 0 /* Reserved */ |
 		f_nx | 0 /* Reserved */ | F(MMXEXT) | F(MMX) |
-		F(FXSR) | F(FXSR_OPT) | f_gbpages | f_rdtscp |
+		F(FXSR) | F(FXSR_OPT) | f_gbpages | F(RDTSCP) |
 		0 /* Reserved */ | f_lm | F(3DNOWEXT) | F(3DNOW);
 	/* cpuid 1.ecx */
 	const u32 kvm_cpuid_1_ecx_x86_features =

arch/x86/kvm/vmx/vmx.c

@@ -7143,6 +7143,10 @@ static void vmx_set_supported_cpuid(struct kvm_cpuid_entry2 *entry)
 		    boot_cpu_has(X86_FEATURE_OSPKE))
 			cpuid_entry_set(entry, X86_FEATURE_PKU);
 		break;
+	case 0x80000001:
+		if (!cpu_has_vmx_rdtscp())
+			cpuid_entry_clear(entry, X86_FEATURE_RDTSCP);
+		break;
 	default:
 		break;
 	}