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Sat, 22 Mar 2025 07:36:26 -0700 (PDT) Message-ID: <1083f491-2da2-4ba3-b85b-53a057af0e65@kernel.dk> Date: Sat, 22 Mar 2025 08:36:25 -0600 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH next 0/3] iov: Optimise user copies To: David Laight , linux-kernel@vger.kernel.org Cc: Linus Torvalds , David Howells , Matthew Wilcox , Andrew Morton , Alexander Viro References: <20250321224557.3847-1-david.laight.linux@gmail.com> Content-Language: en-US From: Jens Axboe In-Reply-To: <20250321224557.3847-1-david.laight.linux@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 3/21/25 4:45 PM, David Laight wrote: > The speculation barrier in access_ok() is expensive. > > The first patch removes the initial checks when reading the iovec[]. > The checks are repeated before the actual copy. > > The second patch uses 'user address masking' if supported. > > The third removes a lot of code for single entry iovec[]. Looks good to me: Reviewed-by: Jens Axboe -- Jens Axboe