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Message-ID: <5382d3a8-08e0-5429-0cd3-36f9c69197e1@gmail.com> Date: Fri, 11 May 2018 15:25:18 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Currently, there is no read barrier between reading the index (kfifo.in) and fetching the real data from the fifo. I am afraid that will cause the vfifo is observed as not empty however the data is not actually ready for read. Right? Thanks!