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[87.94.132.183]) by smtp.gmail.com with ESMTPSA id 2adb3069b0e04-543ebe0fbcdsm1242277e87.60.2025.02.03.00.17.22 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 03 Feb 2025 00:17:24 -0800 (PST) Message-ID: Date: Mon, 3 Feb 2025 10:17:22 +0200 Precedence: bulk X-Mailing-List: iommu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v8 2/2] rust: add dma coherent allocator abstraction. To: Christoph Hellwig , Danilo Krummrich Cc: Greg KH , Linus Torvalds , Miguel Ojeda , daniel.almeida@collabora.com, aliceryhl@google.com, robin.murphy@arm.com, rust-for-linux@vger.kernel.org, Miguel Ojeda , Alex Gaynor , Boqun Feng , Gary Guo , =?UTF-8?Q?Bj=C3=B6rn_Roy_Baron?= , Benno Lossin , Andreas Hindborg , Trevor Gross , Valentin Obst , open list , Marek Szyprowski , airlied@redhat.com, "open list:DMA MAPPING HELPERS" References: <20250108151858.GB24499@lst.de> <20250109080812.GA20431@lst.de> <20250110083955.GA5395@lst.de> <20250128092334.GA28548@lst.de> <20250131075751.GA16720@lst.de> Content-Language: en-US From: Abdiel Janulgue In-Reply-To: <20250131075751.GA16720@lst.de> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Hi, On 31/01/2025 09:57, Christoph Hellwig wrote: > > Which doesn't help me a bit. Every additional bit that the another > language creeps in drastically reduces the maintainability of the kernel > as an integrated project. The only reason Linux managed to survive so > long is by not having internal boundaries, and adding another language > complely breaks this. You might not like my answer, but I will do > everything I can do to stop this. This is NOT because I hate Rust. > While not my favourite language it's definitively one of the best new > ones and I encourage people to use it for new projects where it fits. > I do not want it anywhere near a huge C code base that I need to > maintain. > I do acknowledge your reservations about the possible maintenance burden due to the introduction of a rust (or another language) consumer of the dma-api. But I was hoping that we could arrive at some sort of common ground? If this rust middle-layer abstraction is unacceptable to you, could you perhaps suggest a solution so that all rust device driver don’t end up with redundant dma coherent allocator rust code? Could the rust team do something about it? Thanks, Abdiel