diff --git a/executer/kernel/control.c b/executer/kernel/control.c
index aa34a436..4b0c837d 100644
--- a/executer/kernel/control.c
+++ b/executer/kernel/control.c
@@ -35,8 +35,6 @@
 #include <asm/io.h>
 #include "mcctrl.h"
 
-#define DEBUG 1
-
 #ifdef DEBUG
 #define dprintk printk
 #else
diff --git a/executer/kernel/syscall.c b/executer/kernel/syscall.c
index 4250375c..6b33326d 100644
--- a/executer/kernel/syscall.c
+++ b/executer/kernel/syscall.c
@@ -46,7 +46,7 @@
 
 #define ALIGN_WAIT_BUF(z)   (((z + 63) >> 6) << 6)
 
-#define SC_DEBUG
+//#define SC_DEBUG
 
 #ifdef SC_DEBUG
 #define	dprintk(...)	printk(__VA_ARGS__)
@@ -1158,8 +1158,6 @@ static void clear_pte_range(uintptr_t start, uintptr_t len)
 	return;
 }
 
-/* xxx */
-
 static int writecore(ihk_os_t os, unsigned long rcoretable, int chunks) {
 	struct file *file;
 	struct coretable *coretable;
diff --git a/kernel/mem.c b/kernel/mem.c
index c7d73f3c..f940abbf 100644
--- a/kernel/mem.c
+++ b/kernel/mem.c
@@ -34,7 +34,7 @@
 #include <cls.h>
 #include <page.h>
 
-#define DEBUG_PRINT_MEM
+//#define DEBUG_PRINT_MEM
 
 #ifdef DEBUG_PRINT_MEM
 #define	dkprintf(...)	kprintf(__VA_ARGS__)