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Tue, 15 Apr 2025 09:15:44 -0700 (PDT) Message-ID: <6323c463-0d42-4c5f-a7d1-8739dcd34487@kernel.dk> Date: Tue, 15 Apr 2025 10:15:43 -0600 Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] block: ensure that struct blk_mq_alloc_data is fully initialized To: Bart Van Assche , "linux-block@vger.kernel.org" References: <1720cf81-6170-4cac-abf3-e19a4493653b@kernel.dk> <4b0eee16-a37b-4770-95f0-c5f02160e0da@kernel.dk> <77aa1c61-dc33-47d0-854d-22e4f1cae60e@acm.org> Content-Language: en-US From: Jens Axboe In-Reply-To: <77aa1c61-dc33-47d0-854d-22e4f1cae60e@acm.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 4/15/25 10:13 AM, Bart Van Assche wrote: > On 4/15/25 8:59 AM, Jens Axboe wrote: >> On 4/15/25 9:50 AM, Bart Van Assche wrote: >>> On 4/15/25 7:51 AM, Jens Axboe wrote: >>>> On x86, rep stos will be emitted to clear the the blk_mq_alloc_data >>>> struct, as not all members are being initialied. >>> >>> "Partial initialization" never happens in the C language when >>> initializing a data structure. If a data structure is initialized, >>> members that have not been specified are initialized to zero (the >>> compiler is not required to initialize padding bytes). In other words, >>> the description of this patch needs to be improved. >> >> How is the description inaccurate? As not all members are being >> explicitly initialized, rep stos is emitted to do so. > > Hi Jens, > > I think we agree if the word "explicit" would be added to the patch > description. Sure -- Jens Axboe