diff --git a/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/SAGetopt.java b/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/SAGetopt.java
index d23a057f584..65648a6add8 100644
--- a/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/SAGetopt.java
+++ b/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/SAGetopt.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2015, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -59,7 +59,8 @@ public class SAGetopt {
         }
 
         if (! _argv[_optind].isEmpty() && _argv[_optind].charAt(0) == '-') {
-            throw new SAGetoptException("Argument is expected for '" + opt + "'");
+            throw new SAGetoptException("Successor argument without leading - is expected for '" + opt +
+                                        "' but we got '" + _argv[_optind] + "'");
         }
 
         _optarg = _argv[_optind];
diff --git a/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/SALauncher.java b/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/SALauncher.java
index b873eb1e55b..b884058a3a2 100644
--- a/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/SALauncher.java
+++ b/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/SALauncher.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, 2021, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2015, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -500,7 +500,8 @@ public class SALauncher {
                 func.accept(oldArgs);
             }
         } catch (SAGetoptException e) {
-            System.err.println(e.getMessage());
+            System.err.println("SA agent option related exception occurred: " + e.getMessage());
+            e.printStackTrace();
             toolHelp(args[0]);
             // Exit with error status
             System.exit(1);
diff --git a/test/hotspot/jtreg/serviceability/sa/sadebugd/SADebugDTest.java b/test/hotspot/jtreg/serviceability/sa/sadebugd/SADebugDTest.java
index 49f90f7f9fd..4ba76034276 100644
--- a/test/hotspot/jtreg/serviceability/sa/sadebugd/SADebugDTest.java
+++ b/test/hotspot/jtreg/serviceability/sa/sadebugd/SADebugDTest.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2016, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -101,12 +101,18 @@ public class SADebugDTest {
                 int registryPort = REGISTRY_DEFAULT_PORT;
                 if (useRegistryPort) {
                     registryPort = Utils.findUnreservedFreePort(REGISTRY_DEFAULT_PORT);
+                    if (registryPort == -1) {
+                        throw new RuntimeException("Cannot find a registryPort, findUnreservedFreePort returns -1");
+                    }
                     jhsdbLauncher.addToolArg("--registryport");
                     jhsdbLauncher.addToolArg(Integer.toString(registryPort));
                 }
 
                 final int rmiPort = useRmiPort ? Utils.findUnreservedFreePort(REGISTRY_DEFAULT_PORT, registryPort) : -1;
                 if (useRmiPort) {
+                    if (rmiPort == -1) {
+                        throw new RuntimeException("Cannot find an rmiPort, findUnreservedFreePort returns -1");
+                    }
                     jhsdbLauncher.addToolArg("--rmiport");
                     jhsdbLauncher.addToolArg(Integer.toString(rmiPort));
                 }