diff --git a/board/k210-emulator/board.c b/board/k210-emulator/board.c
index 0b9f6fa6..20a5441c 100644
--- a/board/k210-emulator/board.c
+++ b/board/k210-emulator/board.c
@@ -54,7 +54,6 @@ Modification:
 extern x_base cpu2_boot_flag;
 extern void entry(void);
 extern void SecondaryCpuCStart(void);
-extern void ShutdownCpu(void);
 extern int IoConfigInit(void);
 extern int HwSpiInit(void);
 extern int HwI2cInit(void);
@@ -183,25 +182,3 @@ void HwCpuReset(void)
 
 SHELL_EXPORT_CMD(SHELL_CMD_PERMISSION(0)|SHELL_CMD_TYPE(SHELL_TYPE_CMD_FUNC)|SHELL_CMD_PARAM_NUM(0),
                                                 reboot, HwCpuReset,  reset machine );
-static void (*pre_shutdown_action)(void *);
-static void *pre_shutdown_action_arg;
-
-void SetPreShutdownAction(void (*func)(void *), void *arg)
-{
-    pre_shutdown_action = func;
-    pre_shutdown_action_arg = arg;
-}
-
-void CmdShutdown()
-{
-#ifdef FS_VFS
-    SyncOpenedFiles();
-#endif
-    if (pre_shutdown_action != NULL)
-        pre_shutdown_action(pre_shutdown_action_arg);
-
-    ShutdownCpu();
-}
-
-SHELL_EXPORT_CMD(SHELL_CMD_PERMISSION(0)|SHELL_CMD_TYPE(SHELL_TYPE_CMD_FUNC)|SHELL_CMD_PARAM_NUM(0),
-                                               shutdown,CmdShutdown,shutdown machine); 
diff --git a/kernel/kernel_service/xs_service.c b/kernel/kernel_service/xs_service.c
index 7183f28c..f6acd21d 100644
--- a/kernel/kernel_service/xs_service.c
+++ b/kernel/kernel_service/xs_service.c
@@ -39,7 +39,7 @@ extern void ShowMemory(void);
 extern long ShowSem(void);
 extern long ShowEvent(void);
 extern long ShowMutex(void);
-//extern long ShowMemPool(void);
+//extern long ShowGatherMem(void);
 extern long ShowMsgQueue(void);
 //extern long showdevice(void);
 extern long ShowTimer(void);
@@ -75,7 +75,7 @@ uintptr_t KsPrintInfo(uint32_t knum,uintptr_t *param, uint8_t num )
 #endif
        break;
     case 6:
-       //ShowMemPool();
+       //ShowGatherMem();
        break;
     case 7:
 #ifdef KERNEL_MESSAGEQUEUE
diff --git a/kernel/kernel_test/test_gatherblock.c b/kernel/kernel_test/test_gatherblock.c
index c05ed42e..a6e17abf 100644
--- a/kernel/kernel_test/test_gatherblock.c
+++ b/kernel/kernel_test/test_gatherblock.c
@@ -21,7 +21,7 @@
 #include <xiuos.h>
 #include <string.h>
 
-extern long ShowMemPool(void);
+extern long ShowGatherMem(void);
 extern void ShowMemory(void);
 extern void ShowBuddy(void);
 /**************************single gatherblock test sample***********************************/
@@ -93,7 +93,7 @@ int SingleGatherblockTest(char * parameter)
     if(0 == strncmp("static", parameter, strlen("static"))){
         KPrintf("test static create gatherblock.\n");
         InitMemGather(&gm, "mp_s", &mempool[0], sizeof(mempool), 80);
-        ShowMemPool();
+        ShowGatherMem();
     }
 
     if(0 == strncmp("dynamic", parameter, strlen("dynamic"))){
@@ -105,7 +105,7 @@ int SingleGatherblockTest(char * parameter)
             return -1;
         }
 
-        ShowMemPool();
+        ShowGatherMem();
     }
     /* create task1, alloc memory blocks */
     tid1 = KTaskCreate("task1", Task1GmAlloc, parameter,
@@ -204,7 +204,7 @@ int MultipleGatherblockTest(void)
         KPrintf("create m_gm_d2 failed.");
         CHECK(0);
     }
-    ShowMemPool();
+    ShowGatherMem();
 
     /* create task1, alloc memory blocks */
     m_tid1 = KTaskCreate("task1_m", Task1AllocEntry, NONE,
@@ -443,7 +443,7 @@ int RandomAllocFreeTest(void *parameter)
     if(0 == strncmp("static", parameter, strlen("static"))){
         KPrintf("test static create gatherblock-%s.\n",parameter);
         InitMemGather(&random_static_gm, "ran_mp_s", &dynamic_mempool[0], sizeof(dynamic_mempool), 80);
-        ShowMemPool();
+        ShowGatherMem();
     }else{
         KPrintf("test dynamic create gatherblock.\n");
         random_dynamic_gm = CreateMemGather("ran_mp_d",40,80);
@@ -451,7 +451,7 @@ int RandomAllocFreeTest(void *parameter)
             KPrintf("%s: allocate failure.\n",__func__);
             return -1;
         }
-        ShowMemPool();
+        ShowGatherMem();
     }
     /* create task1, alloc memory blocks */
     random_tid1 = KTaskCreate("r_task1", RandomTask1GmAlloc, parameter,
diff --git a/kernel/kernel_test/test_main.c b/kernel/kernel_test/test_main.c
index ecd6db65..74703a5b 100644
--- a/kernel/kernel_test/test_main.c
+++ b/kernel/kernel_test/test_main.c
@@ -88,21 +88,25 @@ int TestMain(int argc, char*argv[])
 			break;
 		case MEM:
 #ifdef KERNEL_TEST_MEM
+		if (argc > 2)
 		    TestMem(argc-2,&argv[2]);
 #endif
 			break;
 	    case TIMER:
 #ifdef KERNEL_TEST_TIMER
+		if (argc > 2)
             TestTmr(argc-2,&argv[2]);
 #endif
             break;
 		case GATHERBLOCK:
 #ifdef KERNEL_TEST_MEM
+		if (argc > 2)
 	        TestGatherblock(&argv[2]);
 #endif
 	        break;
 		case SCHED:
 #ifdef KERNEL_TEST_SCHED
+		if (argc > 2)
 			TestTaskReadyAndSched(argc-2, &argv[2]);
 #endif
 			break;
@@ -112,6 +116,7 @@ int TestMain(int argc, char*argv[])
 #endif
 		case REALTIME:
 #ifdef KERNEL_TEST_REALTIME
+		if (argc > 2)
 			TestRealtime(argc-2, &argv[2]);
 #endif
 		default:
diff --git a/kernel/memory/byte_manage.c b/kernel/memory/byte_manage.c
index a92980cc..fdebc105 100644
--- a/kernel/memory/byte_manage.c
+++ b/kernel/memory/byte_manage.c
@@ -66,7 +66,7 @@ struct DynamicAllocNode
  */
 struct DynamicFreeNode
 {
-	uint32 size;                /* the size of dynamicAllocNode */
+	x_size_t size;                /* the size of dynamicAllocNode */
 	uint32 prev_adj_size;       /* the size of the previous adjacent node, (dynamic alloc node or dynamic free node */
 	
 	struct DynamicFreeNode *next;
@@ -341,7 +341,7 @@ static void* BigMemMalloc(struct DynamicBuddyMemory *dynamic_buddy, x_size_t siz
 	};
 
 	/* get the best-fit freeNode */
-	if (node) {
+	if (node && (node->size > allocsize)) {
 		struct DynamicFreeNode *remainder;
 		struct DynamicFreeNode *next;
 		x_size_t remaining;