[PATCH] uacce: unmap remaining mmapping from user space

[zhangfei]

Hi, Zaibo

On 2020/2/24 下午3:17, Xu Zaibo wrote:
>>   @@ -585,6 +595,13 @@ void uacce_remove(struct uacce_device *uacce)
>>           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);
> Should we unmap them at the first of 'uacce_remove',  and before 
> 'uacce_put_queue'?
>
We can do this,
Though it does not matter, since user space can not interrupt kernel 
function uacce_remove.

Thanks