[PATCH v7 8/10] KVM: arm64: Add capability to advertise ptrauth for guest

[Amit Daniel Kachhap]

This patch advertises the capability of pointer authentication
when system supports pointer authentication and VHE mode present.

Signed-off-by: Amit Daniel Kachhap <amit.kachhap@xxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Marc Zyngier <marc.zyngier@xxxxxxx>
Cc: Christoffer Dall <christoffer.dall@xxxxxxx>
Cc: kvmarm@xxxxxxxxxxxxxxxxxxxxx
---
 arch/arm64/kvm/reset.c   | 4 ++++
 include/uapi/linux/kvm.h | 1 +
 2 files changed, 5 insertions(+)

diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c
index 00f0639..a3b269e 100644
--- a/arch/arm64/kvm/reset.c
+++ b/arch/arm64/kvm/reset.c
@@ -92,6 +92,10 @@ int kvm_arch_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 	case KVM_CAP_ARM_VM_IPA_SIZE:
 		r = kvm_ipa_limit;
 		break;
+	case KVM_CAP_ARM_PTRAUTH:
+		r = has_vhe() && system_supports_address_auth() &&
+			system_supports_generic_auth();
+		break;
 	default:
 		r = 0;
 	}
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 6d4ea4b..a553477 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -988,6 +988,7 @@ struct kvm_ppc_resize_hpt {
 #define KVM_CAP_ARM_VM_IPA_SIZE 165
 #define KVM_CAP_MANUAL_DIRTY_LOG_PROTECT 166
 #define KVM_CAP_HYPERV_CPUID 167
+#define KVM_CAP_ARM_PTRAUTH 168
 
 #ifdef KVM_CAP_IRQ_ROUTING
 
-- 
2.7.4