/* dispose of the old data from an updated user defined key  */
static void user_update_rcu_disposal(struct rcu_head *rcu)
/* dispose of the old data from an updated user defined key  */
static void user_update_rcu_disposal(struct rcu_head *rcu)
{
	struct user_key_payload *upayload;
	upayload = container_of(rcu, struct user_key_payload, rcu);
	kfree(upayload);
}