Michael Chan [off-list ref] 于2019年8月1日周四 上午1:58写道：

On Wed, Jul 31, 2019 at 5:22 AM Chuhong Yuan [off-list ref] wrote:

quoted

 static void cnic_ctx_wr(struct cnic_dev *dev, u32 cid_addr, u32 off, u32 val)

@@ -494,7 +494,7 @@ int cnic_register_driver(int ulp_type, struct cnic_ulp_ops *ulp_ops)
        }
        read_unlock(&cnic_dev_lock);

-       atomic_set(&ulp_ops->ref_count, 0);
+       refcount_set(&ulp_ops->ref_count, 0);
        rcu_assign_pointer(cnic_ulp_tbl[ulp_type], ulp_ops);
        mutex_unlock(&cnic_lock);

Willem's comment applies here too.  The driver needs to be modified to
count from 1 to use refcount_t.

Thanks.

I have revised this problem but find the other two refcounts -
cnic_dev::ref_count
and cnic_sock::ref_count have no set.
I am not sure where to initialize them to 1.

Besides, should ulp_ops->ref_count be set to 0 when unregistered?