problem about insmod

Question

hello all
I am just beginning to play with linux kernel,but  I got blocked while insertings my first simple module which just log some message in the init and exit function.when I invoke insmod hello.ko,a segmentation fault arised,how can I fix this problem.
here is my code:
/*
*helloworld.c  Hello World! As a kernel Module
*/

#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>

/*
*hello_init : the init function
*/
static int hello_init(void)
{
    //printk(KERN_ALERT "hello world startup.\n");
        return 0;
}

/*
*hello_exit : the exit function
*/
static void hello_exit(void)
{
    //printk(KERN_ALERT "hello world exit.\n");
}

module_init(hello_init);
module_exit(hello_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("alex");

Answer 1

what log?

Answer 2

ok,I had just made a foolish mistake that the kernel running in the system was not exactly the one I bulilt my module,although the versions are the same.Maybe the segmentation fault was caused by the mismatch of the System.map.Any ideas??