* more reliable check signature
diff --git a/bootstub.c b/bootstub.c
index cfbce7b..79a3a2b 100644
--- a/bootstub.c
+++ b/bootstub.c
@@ -68,7 +68,7 @@
 static int get_32bit_entry(unsigned char *ptr)
 {
 	while (1){
-		if (*(u32 *)ptr == SETUP_SIGNATURE && *(u8*)(ptr+4) == 0)
+		if (*(u32 *)ptr == SETUP_SIGNATURE && *(u32 *)(ptr+4) == 0)
 			break;
 		ptr++;
 	}
@@ -78,14 +78,10 @@
 
 int main(void)
 {
-	*(char*)0xb8000='A';
 	setup_idt();
-	*(char*)0xb8000='B';
 	setup_gdt();
-	*(char*)0xb8000='C';
 	setup_boot_params((struct boot_params *)BOOT_PARAMS_OFFSET, 
 		(struct setup_header*)SETUP_HEADER_OFFSET);
-	*(char*)0xb8000='D';
 	return get_32bit_entry((unsigned char *)BZIMAGE_OFFSET);
 }