linux-kernel - [PATCH v3 46/57] KVM: x86: Drop unnecessary check that cpuid_entry2

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Message-ID: <20241128013424.4096668-47-seanjc@google.com>
Date: Wed, 27 Nov 2024 17:34:13 -0800
From: Sean Christopherson <seanjc@...gle.com>
To: Paolo Bonzini <pbonzini@...hat.com>, Sean Christopherson <seanjc@...gle.com>, 
	Vitaly Kuznetsov <vkuznets@...hat.com>, Jarkko Sakkinen <jarkko@...nel.org>
Cc: kvm@...r.kernel.org, linux-sgx@...r.kernel.org, 
	linux-kernel@...r.kernel.org, Maxim Levitsky <mlevitsk@...hat.com>, 
	Hou Wenlong <houwenlong.hwl@...group.com>, Xiaoyao Li <xiaoyao.li@...el.com>, 
	Kechen Lu <kechenl@...dia.com>, Oliver Upton <oliver.upton@...ux.dev>, 
	Binbin Wu <binbin.wu@...ux.intel.com>, Yang Weijiang <weijiang.yang@...el.com>, 
	Robert Hoo <robert.hoo.linux@...il.com>
Subject: [PATCH v3 46/57] KVM: x86: Drop unnecessary check that
 cpuid_entry2_find() returns right leaf

Drop an unnecessary check that kvm_find_cpuid_entry_index(), i.e.
cpuid_entry2_find(), returns the correct leaf when getting CPUID.0x7.0x0
to update X86_FEATURE_OSPKE.  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.

Reviewed-by: Maxim Levitsky <mlevitsk@...hat.com>
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 16cfa839e734..7481926a0291 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -291,7 +291,7 @@ void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu)
 	}
 
 	best = kvm_find_cpuid_entry_index(vcpu, 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));
 
-- 
2.47.0.338.g60cca15819-goog