diff --git a/kernel/model/conf.go b/kernel/model/conf.go
index 1c13074dd..76a215ef0 100644
--- a/kernel/model/conf.go
+++ b/kernel/model/conf.go
@@ -693,7 +693,9 @@ func Close(force, setCurrentWorkspace bool, execInstallPkg int) (exitCode int) {
 	go func() {
 		time.Sleep(500 * time.Millisecond)
 		logging.LogInfof("exited kernel")
-		util.WebSocketServer.Close()
+		if nil != util.WebSocketServer {
+			util.WebSocketServer.Close()
+		}
 		util.HttpServing = false
 		os.Exit(logging.ExitCodeOk)
 	}()