void tty_unregister_device(struct tty_driver *driver, unsigned index)
{
	device_destroy(tty_class,
		MKDEV(driver->major, driver->minor_start) + index);
	if (!(driver->flags & TTY_DRIVER_DYNAMIC_ALLOC)) {
		cdev_del(driver->cdevs[index]);
		driver->cdevs[index] = NULL;
	}
}

The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.