static void con_start(struct tty_struct *tty)
{
	int console_num;
	if (!tty)
		return;
	console_num = tty->index;
	if (!vc_cons_allocated(console_num))
		return;
	vt_kbd_con_start(console_num);
}
static void con_start(struct tty_struct *tty)
{
	int console_num;
	if (!tty)
		return;
	console_num = tty->index;
	if (!vc_cons_allocated(console_num))
		return;
	vt_kbd_con_start(console_num);
}