Hi, ZaiboI think it matters :)
On 2020/2/24 äå3:17, Xu Zaibo wrote:
We can do this,@@ -585,6 +595,13 @@ void uacce_remove(struct uacce_device *uacce)Should we unmap them at the first of 'uacce_remove', and before 'uacce_put_queue'?
cdev_device_del(uacce->cdev, &uacce->dev);
xa_erase(&uacce_xa, uacce->dev_id);
put_device(&uacce->dev);
+
+ /*
+ * unmap remainning mapping from user space, preventing user still
+ * access the mmaped area while parent device is already removed
+ */
+ if (uacce->inode)
+ unmap_mapping_range(uacce->inode->i_mapping, 0, 0, 1);
Though it does not matter, since user space can not interrupt kernel function uacce_remove.
Thanks
.