[PATCH v23 06/14] KVM: arm64: Don't call vcpu_set_pauth_traps for pKVM host

[Suzuki K Poulose <suzuki.poulose@arm.com>]

vcpu_set_pauth_traps() bails out and does nothing for pKVM hosts.
Clean this up by moving the is_protected_kvm_enabled() check to the
caller, in preparation for adding VM specific vcpu load/put callbacks.

While at it, do an early return if the vcpu doesn't have ptrauth.

No functional changes

Reviewed-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
---
Changes since v19:
 - New patch, since addition of this to the Refactoring patch makes it a bit
   more bigger and harder to review
---
 arch/arm64/kvm/arm.c | 52 +++++++++++++++++++++++---------------------
 1 file changed, 27 insertions(+), 25 deletions(-)

diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index bcec14c587119..50b84065ead1a 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -631,33 +631,34 @@ void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
 
 static void vcpu_set_pauth_traps(struct kvm_vcpu *vcpu)
 {
-	if (vcpu_has_ptrauth(vcpu) && !is_protected_kvm_enabled()) {
-		/*
-		 * Either we're running an L2 guest, and the API/APK bits come
-		 * from L1's HCR_EL2, or API/APK are both set.
-		 */
-		if (unlikely(is_nested_ctxt(vcpu))) {
-			u64 val;
+	if (!vcpu_has_ptrauth(vcpu))
+		return;
 
-			val = __vcpu_sys_reg(vcpu, HCR_EL2);
-			val &= (HCR_API | HCR_APK);
-			vcpu->arch.hcr_el2 &= ~(HCR_API | HCR_APK);
-			vcpu->arch.hcr_el2 |= val;
-		} else {
-			vcpu->arch.hcr_el2 |= (HCR_API | HCR_APK);
-		}
+	/*
+	 * Either we're running an L2 guest, and the API/APK bits come
+	 * from L1's HCR_EL2, or API/APK are both set.
+	 */
+	if (unlikely(is_nested_ctxt(vcpu))) {
+		u64 val;
 
-		/*
-		 * Save the host keys if there is any chance for the guest
-		 * to use pauth, as the entry code will reload the guest
-		 * keys in that case.
-		 */
-		if (vcpu->arch.hcr_el2 & (HCR_API | HCR_APK)) {
-			struct kvm_cpu_context *ctxt;
+		val = __vcpu_sys_reg(vcpu, HCR_EL2);
+		val &= (HCR_API | HCR_APK);
+		vcpu->arch.hcr_el2 &= ~(HCR_API | HCR_APK);
+		vcpu->arch.hcr_el2 |= val;
+	} else {
+		vcpu->arch.hcr_el2 |= (HCR_API | HCR_APK);
+	}
 
-			ctxt = this_cpu_ptr_hyp_sym(kvm_hyp_ctxt);
-			ptrauth_save_keys(ctxt);
-		}
+	/*
+	 * Save the host keys if there is any chance for the guest
+	 * to use pauth, as the entry code will reload the guest
+	 * keys in that case.
+	 */
+	if (vcpu->arch.hcr_el2 & (HCR_API | HCR_APK)) {
+		struct kvm_cpu_context *ctxt;
+
+		ctxt = this_cpu_ptr_hyp_sym(kvm_hyp_ctxt);
+		ptrauth_save_keys(ctxt);
 	}
 }
 
@@ -749,7 +750,8 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 	else
 		vcpu->arch.hcr_el2 |= HCR_TWI;
 
-	vcpu_set_pauth_traps(vcpu);
+	if (!is_protected_kvm_enabled())
+		vcpu_set_pauth_traps(vcpu);
 
 	if (is_protected_kvm_enabled()) {
 		kvm_call_hyp_nvhe(__pkvm_vcpu_load,
-- 
2.43.0