Commit 0fcf86f0 authored by Vitaly Kuznetsov's avatar Vitaly Kuznetsov Committed by Paolo Bonzini
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KVM: x86: Add a KVM-only leaf for CPUID_8000_0007_EDX 



CPUID_8000_0007_EDX may come handy when X86_FEATURE_CONSTANT_TSC
needs to be checked.

No functional change intended.

Signed-off-by: default avatarVitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: default avatarSean Christopherson <seanjc@google.com>
Message-Id: <20221013095849.705943-3-vkuznets@redhat.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent b961aa75

arch/x86/kvm/cpuid.c

+6 −2
Original line number Diff line number Diff line
@@ -701,6 +701,10 @@ void kvm_set_cpu_caps(void) 
	if (!tdp_enabled && IS_ENABLED(CONFIG_X86_64))

		kvm_cpu_cap_set(X86_FEATURE_GBPAGES);



	kvm_cpu_cap_init_kvm_defined(CPUID_8000_0007_EDX,

		SF(CONSTANT_TSC)

	);



	kvm_cpu_cap_mask(CPUID_8000_0008_EBX,

		F(CLZERO) | F(XSAVEERPTR) |

		F(WBNOINVD) | F(AMD_IBPB) | F(AMD_IBRS) | F(AMD_SSBD) | F(VIRT_SSBD) |
@@ -1153,8 +1157,8 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function) 
		entry->edx &= ~GENMASK(17, 16);

		break;

	case 0x80000007: /* Advanced power management */

		/* invariant TSC is CPUID.80000007H:EDX[8] */

		entry->edx &= (1 << 8);

		cpuid_entry_override(entry, CPUID_8000_0007_EDX);



		/* mask against host */

		entry->edx &= boot_cpu_data.x86_power;

		entry->eax = entry->ebx = entry->ecx = 0;

arch/x86/kvm/reverse_cpuid.h

+7 −0
Original line number Diff line number Diff line
@@ -14,6 +14,7 @@ 
enum kvm_only_cpuid_leafs {

	CPUID_12_EAX	 = NCAPINTS,

	CPUID_7_1_EDX,

	CPUID_8000_0007_EDX,

	NR_KVM_CPU_CAPS,



	NKVMCAPINTS = NR_KVM_CPU_CAPS - NCAPINTS,
@@ -42,6 +43,9 @@ enum kvm_only_cpuid_leafs { 
#define X86_FEATURE_AVX_NE_CONVERT      KVM_X86_FEATURE(CPUID_7_1_EDX, 5)

#define X86_FEATURE_PREFETCHITI         KVM_X86_FEATURE(CPUID_7_1_EDX, 14)



/* CPUID level 0x80000007 (EDX). */

#define KVM_X86_FEATURE_CONSTANT_TSC	KVM_X86_FEATURE(CPUID_8000_0007_EDX, 8)



struct cpuid_reg {

	u32 function;

	u32 index;
@@ -67,6 +71,7 @@ static const struct cpuid_reg reverse_cpuid[] = { 
	[CPUID_12_EAX]        = {0x00000012, 0, CPUID_EAX},

	[CPUID_8000_001F_EAX] = {0x8000001f, 0, CPUID_EAX},

	[CPUID_7_1_EDX]       = {         7, 1, CPUID_EDX},

	[CPUID_8000_0007_EDX] = {0x80000007, 0, CPUID_EDX},

};



/*
@@ -97,6 +102,8 @@ static __always_inline u32 __feature_translate(int x86_feature) 
		return KVM_X86_FEATURE_SGX1;

	else if (x86_feature == X86_FEATURE_SGX2)

		return KVM_X86_FEATURE_SGX2;

	else if (x86_feature == X86_FEATURE_CONSTANT_TSC)

		return KVM_X86_FEATURE_CONSTANT_TSC;



	return x86_feature;

}