Keyboard interrupt handler causing system to freeze - linux-kernel

Question

This is my first stack overflow post (long time lurker), so sorry in advance if this question isn't well worded.
I'm trying to make a kernel module to emulate keypresses when a user presses a button, and using http://www.staerk.de/thorsten/My_Tutorials/Writing_Linux_kernel_modules as an example.
It does simulate a keypress when the module is initialized, but when I send an interrupt and try to run the same code the entire virtual machine freezes.
Here's snippits of my code:
static void got_char(struct work_struct *taskp)
{
struct myprivate *myp = container_of(taskp, struct myprivate, task);
if ((myp->scancode == 0x01) || (myp->scancode == 0x81))
{
printk ("You pressed Esc !\n");
println ("Pressed ESC ! \n");
ch=65;
tty_insert_flip_char(tty, ch, 0);
con_schedule_flip(tty);
}
else if (myp->scancode == 0x1D) {
printk ("You pressed Ctrl!\n");
}
else {
printk("Scancode = %d", myp->scancode);
}
}
irq_handler_t irq_handler(int irq, void *dev_id, struct pt_regs *regs)
{
static int initialised = 0;
/*
* Read keyboard status
*/
myp->scancode = inb(0x60);
if (initialised == 0) {
INIT_WORK(&myp->task, got_char);
initialised = 1;
}
else {
PREPARE_WORK(&myp->task, got_char);
}
schedule_work(&myp->task);
return (irq_handler_t) IRQ_HANDLED;
}
/* Helper method to print stuff to the terminal */
static void println(char *string)
{
tty = current->signal->tty;
(tty->driver->ops)->write (tty, string, strlen(string));
((tty->driver->ops)->write) (tty, "\015\012", 2);
}
/* Initialize the module and Register the IRQ handler */
static int __init keybrd_int_register(void)
{
myp = kmalloc(sizeof (*myp), GFP_KERNEL);
int result;
/* Request IRQ 1, the keyboard IRQ */
result = request_irq (1, (irq_handler_t) irq_handler, IRQF_SHARED, "keyboard_stats_irq", (void *)(irq_handler));
/* Test simulating keypress */
println ("inserting A ! \n");
ch=65;
tty_insert_flip_char(tty, ch, 0);
con_schedule_flip(tty);
if (result)
printk(KERN_INFO "can't get shared interrupt for keyboard\n");
return result;
}
Everything works as expected, except for when ESC is pressed, then my entire system just freezes and I have to restart my VM.
I've looked through many posts and forums online and can't find an answer.
Any suggestions would be appreciated, thanks in advance.