diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index d161b5672c..3184e5b9c3 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -4175,6 +4175,9 @@ qemuBuildMemballoonDevStr(virDomainMemballoonDefPtr dev,
             virBufferAddLit(&buf, "virtio-balloon-ccw");
             break;
         default:
+            virReportError(VIR_ERR_XML_ERROR,
+                           _("memballoon unsupported with address type '%s'"),
+                           virDomainDeviceAddressTypeToString(dev->info.type));
             goto error;
     }