linux-kernel - [PATCH 5/9] KVM: x86: Drop unnecessary check that cpuid_entry2

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Date:   Fri, 10 Nov 2023 15:55:24 -0800
From:   Sean Christopherson <seanjc@...gle.com>
To:     Sean Christopherson <seanjc@...gle.com>,
        Paolo Bonzini <pbonzini@...hat.com>
Cc:     kvm@...r.kernel.org, linux-kernel@...r.kernel.org,
        Maxim Levitsky <mlevitsk@...hat.com>
Subject: [PATCH 5/9] KVM: x86: Drop unnecessary check that cpuid_entry2_find()
 returns right leaf

Drop an unnecessary check that cpuid_entry2_find() returns the correct
leaf when getting CPUID.0x7.0x0 to update X86_FEATURE_OSPKE, as
cpuid_entry2_find() never returns an entry for the wrong function.  And
not that it matters, but cpuid_entry2_find() will always return a precise
match for CPUID.0x7.0x0 since the index is significant.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 arch/x86/kvm/cpuid.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 6777780be6ae..36bd04030989 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -284,7 +284,7 @@ static void __kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu, struct kvm_cpuid_e
 	}
 
 	best = cpuid_entry2_find(entries, nent, 7, 0);
-	if (best && boot_cpu_has(X86_FEATURE_PKU) && best->function == 0x7)
+	if (best && boot_cpu_has(X86_FEATURE_PKU))
 		cpuid_entry_change(best, X86_FEATURE_OSPKE,
 				   kvm_is_cr4_bit_set(vcpu, X86_CR4_PKE));
 
-- 
2.42.0.869.gea05f2083d-goog