From: Binbin Wu <binbin.wu@linux.intel.com>
Date: Thu, 28 Nov 2024 00:43:40 +0000 (-0800)
Subject: KVM: x86: Add a helper to check for user interception of KVM hypercalls
X-Git-Tag: v6.14-rc1~94^2~2^2~4
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=c4c083d95105445ebf1cadfb7d05dd2630976241;p=thirdparty%2Fkernel%2Flinux.git

KVM: x86: Add a helper to check for user interception of KVM hypercalls

Add and use user_exit_on_hypercall() to check if userspace wants to handle
a KVM hypercall instead of open-coding the logic everywhere.

No functional change intended.

Signed-off-by: Binbin Wu <binbin.wu@linux.intel.com>
Reviewed-by: Isaku Yamahata <isaku.yamahata@intel.com>
Reviewed-by: Kai Huang <kai.huang@intel.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
[sean: squash into one patch, keep explicit KVM_HC_MAP_GPA_RANGE check]
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-ID: <20241128004344.4072099-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---

diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 9ffb0fb5aacd3..5eb7a206f4051 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -3627,7 +3627,7 @@ static int snp_begin_psc_msr(struct vcpu_svm *svm, u64 ghcb_msr)
 		return 1; /* resume guest */
 	}
 
-	if (!(vcpu->kvm->arch.hypercall_exit_enabled & (1 << KVM_HC_MAP_GPA_RANGE))) {
+	if (!user_exit_on_hypercall(vcpu->kvm, KVM_HC_MAP_GPA_RANGE)) {
 		set_ghcb_msr(svm, GHCB_MSR_PSC_RESP_ERROR);
 		return 1; /* resume guest */
 	}
@@ -3717,7 +3717,7 @@ static int snp_begin_psc(struct vcpu_svm *svm, struct psc_buffer *psc)
 	bool huge;
 	u64 gfn;
 
-	if (!(vcpu->kvm->arch.hypercall_exit_enabled & (1 << KVM_HC_MAP_GPA_RANGE))) {
+	if (!user_exit_on_hypercall(vcpu->kvm, KVM_HC_MAP_GPA_RANGE)) {
 		snp_complete_psc(svm, VMGEXIT_PSC_ERROR_GENERIC);
 		return 1;
 	}
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 615cba6fe4663..d485a53ac4103 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -10041,7 +10041,7 @@ unsigned long __kvm_emulate_hypercall(struct kvm_vcpu *vcpu, unsigned long nr,
 		u64 gpa = a0, npages = a1, attrs = a2;
 
 		ret = -KVM_ENOSYS;
-		if (!(vcpu->kvm->arch.hypercall_exit_enabled & (1 << KVM_HC_MAP_GPA_RANGE)))
+		if (!user_exit_on_hypercall(vcpu->kvm, KVM_HC_MAP_GPA_RANGE))
 			break;
 
 		if (!PAGE_ALIGNED(gpa) || !npages ||
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index ec623d23d13d2..45dd53284dbde 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -612,4 +612,9 @@ int kvm_sev_es_string_io(struct kvm_vcpu *vcpu, unsigned int size,
 			 unsigned int port, void *data,  unsigned int count,
 			 int in);
 
+static inline bool user_exit_on_hypercall(struct kvm *kvm, unsigned long hc_nr)
+{
+	return kvm->arch.hypercall_exit_enabled & BIT(hc_nr);
+}
+
 #endif