raise error if stack.sh failed
diff --git a/tools/build_kvm.sh b/tools/build_kvm.sh
index dbfb5ce..26a195e 100755
--- a/tools/build_kvm.sh
+++ b/tools/build_kvm.sh
@@ -378,6 +378,10 @@
     done
 
     kill $TAIL_PID
+
+    if grep -q "stack.sh failed" $VM_DIR/console.log; then
+        exit 1
+    fi
     echo ""
     echo "Finished - Zip-a-dee Doo-dah!"
 fi