linux-kernel - [PATCH v2 32/49] KVM: x86: Remove all direct usage of cpuid_entry2

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Date: Fri, 17 May 2024 10:39:09 -0700
From: Sean Christopherson <seanjc@...gle.com>
To: Paolo Bonzini <pbonzini@...hat.com>, Sean Christopherson <seanjc@...gle.com>, 
	Vitaly Kuznetsov <vkuznets@...hat.com>
Cc: kvm@...r.kernel.org, linux-kernel@...r.kernel.org, 
	Hou Wenlong <houwenlong.hwl@...group.com>, Kechen Lu <kechenl@...dia.com>, 
	Oliver Upton <oliver.upton@...ux.dev>, Maxim Levitsky <mlevitsk@...hat.com>, 
	Binbin Wu <binbin.wu@...ux.intel.com>, Yang Weijiang <weijiang.yang@...el.com>, 
	Robert Hoo <robert.hoo.linux@...il.com>
Subject: [PATCH v2 32/49] KVM: x86: Remove all direct usage of cpuid_entry2_find()

Convert all use of cpuid_entry2_find() to kvm_find_cpuid_entry{,index}()
now that cpuid_entry2_find() operates on the vCPU state, i.e. now that
there is no need to use cpuid_entry2_find() directly in order to pass in
non-vCPU state.

To help prevent unwanted usage of cpuid_entry2_find(), #undef
KVM_CPUID_INDEX_NOT_SIGNIFICANT, i.e. force KVM to use
kvm_find_cpuid_entry().

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 arch/x86/kvm/cpuid.c | 28 ++++++++++++++++------------
 1 file changed, 16 insertions(+), 12 deletions(-)

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index d7390ade1c29..699ce4261e9c 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -189,6 +189,12 @@ struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu,
 }
 EXPORT_SYMBOL_GPL(kvm_find_cpuid_entry);
 
+/*
+ * cpuid_entry2_find() and KVM_CPUID_INDEX_NOT_SIGNIFICANT should never be used
+ * directly outside of kvm_find_cpuid_entry() and kvm_find_cpuid_entry_index().
+ */
+#undef KVM_CPUID_INDEX_NOT_SIGNIFICANT
+
 static int kvm_check_cpuid(struct kvm_vcpu *vcpu)
 {
 	struct kvm_cpuid_entry2 *best;
@@ -198,8 +204,7 @@ static int kvm_check_cpuid(struct kvm_vcpu *vcpu)
 	 * The existing code assumes virtual address is 48-bit or 57-bit in the
 	 * canonical address checks; exit if it is ever changed.
 	 */
-	best = cpuid_entry2_find(vcpu, 0x80000008,
-				 KVM_CPUID_INDEX_NOT_SIGNIFICANT);
+	best = kvm_find_cpuid_entry(vcpu, 0x80000008);
 	if (best) {
 		int vaddr_bits = (best->eax & 0xff00) >> 8;
 
@@ -211,7 +216,7 @@ static int kvm_check_cpuid(struct kvm_vcpu *vcpu)
 	 * Exposing dynamic xfeatures to the guest requires additional
 	 * enabling in the FPU, e.g. to expand the guest XSAVE state size.
 	 */
-	best = cpuid_entry2_find(vcpu, 0xd, 0);
+	best = kvm_find_cpuid_entry_index(vcpu, 0xd, 0);
 	if (!best)
 		return 0;
 
@@ -254,7 +259,7 @@ static struct kvm_hypervisor_cpuid kvm_get_hypervisor_cpuid(struct kvm_vcpu *vcp
 	u32 base;
 
 	for_each_possible_hypervisor_cpuid_base(base) {
-		entry = cpuid_entry2_find(vcpu, base, KVM_CPUID_INDEX_NOT_SIGNIFICANT);
+		entry = kvm_find_cpuid_entry(vcpu, base);
 
 		if (entry) {
 			u32 signature[3];
@@ -301,7 +306,7 @@ static u64 cpuid_get_supported_xcr0(struct kvm_vcpu *vcpu)
 {
 	struct kvm_cpuid_entry2 *best;
 
-	best = cpuid_entry2_find(vcpu, 0xd, 0);
+	best = kvm_find_cpuid_entry_index(vcpu, 0xd, 0);
 	if (!best)
 		return 0;
 
@@ -312,7 +317,7 @@ void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu)
 {
 	struct kvm_cpuid_entry2 *best;
 
-	best = cpuid_entry2_find(vcpu, 1, KVM_CPUID_INDEX_NOT_SIGNIFICANT);
+	best = kvm_find_cpuid_entry(vcpu, 1);
 	if (best) {
 		/* Update OSXSAVE bit */
 		if (boot_cpu_has(X86_FEATURE_XSAVE))
@@ -323,22 +328,22 @@ void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu)
 			   vcpu->arch.apic_base & MSR_IA32_APICBASE_ENABLE);
 	}
 
-	best = cpuid_entry2_find(vcpu, 7, 0);
+	best = kvm_find_cpuid_entry_index(vcpu, 7, 0);
 	if (best && boot_cpu_has(X86_FEATURE_PKU) && best->function == 0x7)
 		cpuid_entry_change(best, X86_FEATURE_OSPKE,
 				   kvm_is_cr4_bit_set(vcpu, X86_CR4_PKE));
 
-	best = cpuid_entry2_find(vcpu, 0xD, 0);
+	best = kvm_find_cpuid_entry_index(vcpu, 0xD, 0);
 	if (best)
 		best->ebx = xstate_required_size(vcpu->arch.xcr0, false);
 
-	best = cpuid_entry2_find(vcpu, 0xD, 1);
+	best = kvm_find_cpuid_entry_index(vcpu, 0xD, 1);
 	if (best && (cpuid_entry_has(best, X86_FEATURE_XSAVES) ||
 		     cpuid_entry_has(best, X86_FEATURE_XSAVEC)))
 		best->ebx = xstate_required_size(vcpu->arch.xcr0, true);
 
 	if (!kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT)) {
-		best = cpuid_entry2_find(vcpu, 0x1, KVM_CPUID_INDEX_NOT_SIGNIFICANT);
+		best = kvm_find_cpuid_entry(vcpu, 0x1);
 		if (best)
 			cpuid_entry_change(best, X86_FEATURE_MWAIT,
 					   vcpu->arch.ia32_misc_enable_msr &
@@ -352,8 +357,7 @@ static bool kvm_cpuid_has_hyperv(struct kvm_vcpu *vcpu)
 #ifdef CONFIG_KVM_HYPERV
 	struct kvm_cpuid_entry2 *entry;
 
-	entry = cpuid_entry2_find(vcpu, HYPERV_CPUID_INTERFACE,
-				  KVM_CPUID_INDEX_NOT_SIGNIFICANT);
+	entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_INTERFACE);
 	return entry && entry->eax == HYPERV_CPUID_SIGNATURE_EAX;
 #else
 	return false;
-- 
2.45.0.215.g3402c0e53f-goog