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([2620:10d:c090:400::5:f46f]) by smtp.gmail.com with ESMTPSA id g4-20020a655944000000b003fe4da67980sm9595041pgu.68.2022.06.28.12.38.46 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 28 Jun 2022 12:38:47 -0700 (PDT) Message-ID: <37147b0c-4b11-37df-6c4a-ee2dfeb9cbb7@kernel.dk> Date: Tue, 28 Jun 2022 13:38:44 -0600 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux aarch64; rv:91.0) Gecko/20100101 Thunderbird/91.10.0 Subject: Re: [PATCH][next] io_uring: replace zero-length array with flexible-array member Content-Language: en-US To: "Gustavo A. R. Silva" , Pavel Begunkov Cc: io-uring@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org References: <20220628193320.GA52629@embeddedor> From: Jens Axboe In-Reply-To: <20220628193320.GA52629@embeddedor> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,NICE_REPLY_A,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 6/28/22 1:33 PM, Gustavo A. R. Silva wrote: > There is a regular need in the kernel to provide a way to declare > having a dynamically sized set of trailing elements in a structure. > Kernel code should always use ?flexible array members?[1] for these > cases. The older style of one-element or zero-length arrays should > no longer be used[2]. > > [1] https://en.wikipedia.org/wiki/Flexible_array_member > [2] https://www.kernel.org/doc/html/v5.16/process/deprecated.html#zero-length-and-one-element-arrays Thanks for sending this separately. As mentioned out-of-band, we already have it like this in the io_uring.h header in liburing. Applied for 5.20. -- Jens Axboe