list_for_each_entry(tb, &backend_list, list) {
if (tb->ops == ops) {
list_del(&tb->list);
+ mutex_unlock(&backend_mutex);
+ /*
+ * Wait for any outstanding backend driver ->rcu_head
+ * callbacks to complete post TBO->free_device() ->
+ * call_rcu(), before allowing backend driver module
+ * unload of target_backend_ops->owner to proceed.
+ */
+ rcu_barrier();
kfree(tb);
- break;
+ return;
}
}
mutex_unlock(&backend_mutex);