my machine crashes after inserting the following kernel module - c

Question

I am a total beginner in kernel module programming. I wanted to create a module which reads input from the proc filesystem. With this you should be able to perform operations in the program. I did that with threading. However my machine crashes after inserting the module. Probably I did something wrong. Here is the source code:
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/proc_fs.h>
#include <linux/uaccess.h>
#include <linux/sched.h>
#include <linux/kthread.h>
#include <linux/wait.h>
#include <linux/string.h>
#define PROCFS_MAX_SIZE 1024
#define PROCFS_NAME "test"
MODULE_LICENSE("GPL");
int pid = 1;
static struct proc_dir_entry *Our_Proc_File;
static char procfs_buffer[PROCFS_MAX_SIZE];
static unsigned long procfs_buffer_size = 0;
struct task_struct *task;
static ssize_t procfile_read(struct file *file, char *buffer, size_t buffer_length, loff_t *offset) {
static int flag = 0;
if(flag) {
printk(KERN_INFO "read : END\n");
flag = 0;
return 0;
}
printk(KERN_INFO "read (/proc/%s) : called\n",PROCFS_NAME);
flag = 1;
return snprintf(buffer, buffer_lengh, procfs_buffer);
}
static ssize_t procfile_write(struct file *file,const char *buffer, size_t count, loff_t *offset) {
procfs_buffer_size = count;
if (copy_from_user(procfs_buffer, buffer, procfs_buffer_size)) {
return -EFAULT;
}
return procfs_buffer_size;
}
static int main_prog(void *data) {
int end = 0;
while(!end) {
while(memcmp(procfs_buffer,"\x00",1)==0);
if(memcmp(procfs_buffer,"test",4)) {
printk(KERN_INFO "Test triggered!\n");
}
if(memcmp(procfs_buffer,"exit",4)) {
end++;
}
memset(procfs_buffer, 0, 1024);
}
kthread_stop(task);
}
static struct file_operations fops_struct = {
.read = procfile_read,
.write = procfile_write,
};
int init_module() {
Our_Proc_File = proc_create(PROCFS_NAME, 0666, NULL, &fops_struct);
if (Our_Proc_File == NULL) {
remove_proc_entry(PROCFS_NAME, NULL);
printk(KERN_ALERT "Error: Could not initialize /proc/%s\n", PROCFS_NAME);
return -ENOMEM;
}
task = kthread_run(&main_prog, NULL, "thread");
wake_up_process(task);
printk(KERN_INFO "/proc/%s created\n", PROCFS_NAME);
return 0;
}
void cleanup_module() {
remove_proc_entry(PROCFS_NAME, NULL);
printk(KERN_INFO "/proc/%s removed\n", PROCFS_NAME);
}
Can someone help me?