diff --git a/sys/arm64/arm64/ptrauth.c b/sys/arm64/arm64/ptrauth.c
--- a/sys/arm64/arm64/ptrauth.c
+++ b/sys/arm64/arm64/ptrauth.c
@@ -85,7 +85,7 @@
 static bool
 ptrauth_check(const struct cpu_feat *feat __unused, u_int midr __unused)
 {
-	uint64_t isar1;
+	uint64_t isar;
 	int pac_enable;
 
 	/*
@@ -100,9 +100,6 @@
 		return (false);
 	}
 
-	if (!get_kernel_reg(ID_AA64ISAR1_EL1, &isar1))
-		return (false);
-
 	if (ptrauth_disable())
 		return (false);
 
@@ -111,8 +108,20 @@
 	 * it will also be available on any non-boot CPUs. If this is ever
 	 * not the case we will have to add a quirk.
 	 */
-	return (ID_AA64ISAR1_APA_VAL(isar1) > 0 ||
-	    ID_AA64ISAR1_API_VAL(isar1) > 0);
+	if (get_kernel_reg(ID_AA64ISAR1_EL1, &isar)) {
+		if (ID_AA64ISAR1_APA_VAL(isar) > 0 ||
+		    ID_AA64ISAR1_API_VAL(isar) > 0) {
+			return (true);
+		}
+	}
+
+	if (get_kernel_reg(ID_AA64ISAR2_EL1, &isar)) {
+		if (ID_AA64ISAR2_APA3_VAL(isar) > 0) {
+			return (true);
+		}
+	}
+
+	return (false);
 }
 
 static void