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[82.132.213.27]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-49e60adaee4sm226373935e9.14.2026.09.12.05.45.14 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 12 Sep 2026 05:45:15 -0700 (PDT) Message-ID: <7b126162-f412-41d8-8002-6b31d2795f51@gmail.com> Date: Sat, 12 Sep 2026 13:45:11 +0100 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: [RFC PATCH] misc: fgds: enable GPU-NVMe direct I/O via POSIX and io_uring To: Li Wang , =?UTF-8?Q?Christian_K=C3=B6nig?= , Greg Kroah-Hartman Cc: Arnd Bergmann , Sumit Semwal , linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, io-uring@vger.kernel.org, linux-kernel@vger.kernel.org, Mengmeng Zhao References: <20260908131545.105987-1-liwang@kylinos.cn> <2026090913-landline-encroach-c544@gregkh> <6aed7ecf-d125-40d1-a82d-1a7f62049605@kylinos.cn> <2026090924-corsage-shout-833d@gregkh> <33c9db65-fa30-4d34-9026-98144ce1ed95@amd.com> <9447bb67-96e9-43b3-87c8-db231051fa2d@kylinos.cn> Content-Language: en-US From: Pavel Begunkov In-Reply-To: <9447bb67-96e9-43b3-87c8-db231051fa2d@kylinos.cn> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 9/10/26 04:57, Li Wang wrote: > Hi Christian, > >>>>> Nor why "fgds" is the name, that's going to be hard to remember, does it >>>>> stand for something? >>>>> >>>> "FGDS" stands for Fast GPUDirect Storage. GPUDirect Storage (GDS) is NVIDIA's >>>> technology enabling direct I/O between GPU memory and files on NVMe, >>>> widely used in LLM workloads to bypass CPU overhead. >>> >>> That's nvidia's specific solution, but this works on other devices, >>> right? Or just for that one platform? >> >> That was nvidia's specific and very hacky out of tree solution > Exactly, I completely agree with your viewpoint. In fact, we previously conducted > a deep analysis of NVIDIA's GDS implementation code, which was also one of the > motivations for us to develop fgds. > > Please allow me to introduce NVIDIA's GDS implementation briefly: > NVIDIA introduced two kernel modules: one module called nvidia-fs, and the other module > is a customized NVMe driver replacing the Linux kernel's default NVMe driver. > nvidia-fs creates a device file for every NVIDIA GPU on the machine: /dev/nvidia-fs. I'm not an nvidia expert, but IIRC they switched to P2PDMA, which is supported by the upstream nvme driver. -- Pavel Begunkov