[PATCH v10 2/9] KVM: x86: Add & use kvm_vcpu_is_legal_cr3() to check CR3's legality

[Binbin Wu]

Add and use kvm_vcpu_is_legal_cr3() to check CR3's legality to provide
a clear distinction b/t CR3 and GPA checks. So that kvm_vcpu_is_legal_cr3()
can be adjusted according to new feature(s).

No functional change intended.

Signed-off-by: Binbin Wu <binbin.wu@xxxxxxxxxxxxxxx>
---
 arch/x86/kvm/cpuid.h      | 5 +++++
 arch/x86/kvm/svm/nested.c | 4 ++--
 arch/x86/kvm/vmx/nested.c | 4 ++--
 arch/x86/kvm/x86.c        | 4 ++--
 4 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h
index f61a2106ba90..8b26d946f3e3 100644
--- a/arch/x86/kvm/cpuid.h
+++ b/arch/x86/kvm/cpuid.h
@@ -283,4 +283,9 @@ static __always_inline bool guest_can_use(struct kvm_vcpu *vcpu,
 	return vcpu->arch.governed_features.enabled & kvm_governed_feature_bit(x86_feature);
 }
 
+static inline bool kvm_vcpu_is_legal_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)
+{
+	return kvm_vcpu_is_legal_gpa(vcpu, cr3);
+}
+
 #endif
diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index 96936ddf1b3c..1df801a48451 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -311,7 +311,7 @@ static bool __nested_vmcb_check_save(struct kvm_vcpu *vcpu,
 	if ((save->efer & EFER_LME) && (save->cr0 & X86_CR0_PG)) {
 		if (CC(!(save->cr4 & X86_CR4_PAE)) ||
 		    CC(!(save->cr0 & X86_CR0_PE)) ||
-		    CC(kvm_vcpu_is_illegal_gpa(vcpu, save->cr3)))
+		    CC(!kvm_vcpu_is_legal_cr3(vcpu, save->cr3)))
 			return false;
 	}
 
@@ -520,7 +520,7 @@ static void nested_svm_transition_tlb_flush(struct kvm_vcpu *vcpu)
 static int nested_svm_load_cr3(struct kvm_vcpu *vcpu, unsigned long cr3,
 			       bool nested_npt, bool reload_pdptrs)
 {
-	if (CC(kvm_vcpu_is_illegal_gpa(vcpu, cr3)))
+	if (CC(!kvm_vcpu_is_legal_cr3(vcpu, cr3)))
 		return -EINVAL;
 
 	if (reload_pdptrs && !nested_npt && is_pae_paging(vcpu) &&
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 516391cc0d64..76c9904c6625 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -1085,7 +1085,7 @@ static int nested_vmx_load_cr3(struct kvm_vcpu *vcpu, unsigned long cr3,
 			       bool nested_ept, bool reload_pdptrs,
 			       enum vm_entry_failure_code *entry_failure_code)
 {
-	if (CC(kvm_vcpu_is_illegal_gpa(vcpu, cr3))) {
+	if (CC(!kvm_vcpu_is_legal_cr3(vcpu, cr3))) {
 		*entry_failure_code = ENTRY_FAIL_DEFAULT;
 		return -EINVAL;
 	}
@@ -2912,7 +2912,7 @@ static int nested_vmx_check_host_state(struct kvm_vcpu *vcpu,
 
 	if (CC(!nested_host_cr0_valid(vcpu, vmcs12->host_cr0)) ||
 	    CC(!nested_host_cr4_valid(vcpu, vmcs12->host_cr4)) ||
-	    CC(kvm_vcpu_is_illegal_gpa(vcpu, vmcs12->host_cr3)))
+	    CC(!kvm_vcpu_is_legal_cr3(vcpu, vmcs12->host_cr3)))
 		return -EINVAL;
 
 	if (CC(is_noncanonical_address(vmcs12->host_ia32_sysenter_esp, vcpu)) ||
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index a6b9bea62fb8..6a6d08238e8d 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1271,7 +1271,7 @@ int kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)
 	 * stuff CR3, e.g. for RSM emulation, and there is no guarantee that
 	 * the current vCPU mode is accurate.
 	 */
-	if (kvm_vcpu_is_illegal_gpa(vcpu, cr3))
+	if (!kvm_vcpu_is_legal_cr3(vcpu, cr3))
 		return 1;
 
 	if (is_pae_paging(vcpu) && !load_pdptrs(vcpu, cr3))
@@ -11449,7 +11449,7 @@ static bool kvm_is_valid_sregs(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs)
 		 */
 		if (!(sregs->cr4 & X86_CR4_PAE) || !(sregs->efer & EFER_LMA))
 			return false;
-		if (kvm_vcpu_is_illegal_gpa(vcpu, sregs->cr3))
+		if (!kvm_vcpu_is_legal_cr3(vcpu, sregs->cr3))
 			return false;
 	} else {
 		/*
-- 
2.25.1