diff --git a/kernel/main.c b/kernel/main.c
index 5fbec8a..b4cc7f2 100644
--- a/kernel/main.c
+++ b/kernel/main.c
@@ -63,7 +63,7 @@ int kernel_main()
 
 	
 	printf("kernel initialization is done.\n");
-#define KSHELL_SERIAL
+// #define KSHELL_SERIAL
 #ifndef KSHELL_SERIAL
 	kshell_launch();
   // never reached!