[PATCH v3 20/57] KVM: x86: Do reverse CPUID sanity checks in __feature_leaf()

From: Sean Christopherson
Date: Wed Nov 27 2024 - 20:39:51 EST


Do the compile-time sanity checks on reverse_cpuid in __feature_leaf() so
that higher level APIs don't need to "manually" perform the sanity checks.

No functional change intended.

Reviewed-by: Maxim Levitsky <mlevitsk@xxxxxxxxxx>
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
arch/x86/kvm/cpuid.h | 3 ---
arch/x86/kvm/reverse_cpuid.h | 6 ++++--
2 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h
index d4ece5db7b46..5d0fe3793d75 100644
--- a/arch/x86/kvm/cpuid.h
+++ b/arch/x86/kvm/cpuid.h
@@ -179,7 +179,6 @@ static __always_inline void kvm_cpu_cap_clear(unsigned int x86_feature)
{
unsigned int x86_leaf = __feature_leaf(x86_feature);

- reverse_cpuid_check(x86_leaf);
kvm_cpu_caps[x86_leaf] &= ~__feature_bit(x86_feature);
}

@@ -187,7 +186,6 @@ static __always_inline void kvm_cpu_cap_set(unsigned int x86_feature)
{
unsigned int x86_leaf = __feature_leaf(x86_feature);

- reverse_cpuid_check(x86_leaf);
kvm_cpu_caps[x86_leaf] |= __feature_bit(x86_feature);
}

@@ -195,7 +193,6 @@ static __always_inline u32 kvm_cpu_cap_get(unsigned int x86_feature)
{
unsigned int x86_leaf = __feature_leaf(x86_feature);

- reverse_cpuid_check(x86_leaf);
return kvm_cpu_caps[x86_leaf] & __feature_bit(x86_feature);
}

diff --git a/arch/x86/kvm/reverse_cpuid.h b/arch/x86/kvm/reverse_cpuid.h
index e46220ece83c..1d2db9d529ff 100644
--- a/arch/x86/kvm/reverse_cpuid.h
+++ b/arch/x86/kvm/reverse_cpuid.h
@@ -145,7 +145,10 @@ static __always_inline u32 __feature_translate(int x86_feature)

static __always_inline u32 __feature_leaf(int x86_feature)
{
- return __feature_translate(x86_feature) / 32;
+ u32 x86_leaf = __feature_translate(x86_feature) / 32;
+
+ reverse_cpuid_check(x86_leaf);
+ return x86_leaf;
}

/*
@@ -168,7 +171,6 @@ static __always_inline struct cpuid_reg x86_feature_cpuid(unsigned int x86_featu
{
unsigned int x86_leaf = __feature_leaf(x86_feature);

- reverse_cpuid_check(x86_leaf);
return reverse_cpuid[x86_leaf];
}

--
2.47.0.338.g60cca15819-goog