diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 6dea670257..67555c9be3 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -15504,11 +15504,13 @@ virDomainVideoDefParseXML(virDomainXMLOptionPtr xmlopt,
     }
 
     if (driver_name) {
-        if ((def->backend = virDomainVideoBackendTypeFromString(driver_name)) < 0) {
+        int backend;
+        if ((backend = virDomainVideoBackendTypeFromString(driver_name)) <= 0) {
             virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
                            _("unknown video driver '%s'"), driver_name);
             goto error;
         }
+        def->backend = backend;
     } else {
         def->backend = VIR_DOMAIN_VIDEO_BACKEND_TYPE_DEFAULT;
     }
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index cff33f6682..53bdee22fb 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -1378,7 +1378,7 @@ struct _virDomainWatchdogDef {
 
 /* the backend driver used for virtio interfaces */
 typedef enum {
-    VIR_DOMAIN_VIDEO_BACKEND_TYPE_DEFAULT,
+    VIR_DOMAIN_VIDEO_BACKEND_TYPE_DEFAULT = 0,
     VIR_DOMAIN_VIDEO_BACKEND_TYPE_QEMU,
     VIR_DOMAIN_VIDEO_BACKEND_TYPE_VHOSTUSER,