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[221.241.217.81]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-296509682casm144137395ad.22.2025.11.10.04.18.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 10 Nov 2025 04:18:09 -0800 (PST) Date: Mon, 10 Nov 2025 21:18:05 +0900 Message-ID: From: Hajime Tazaki To: hch@infradead.org Cc: linux-um@lists.infradead.org, ricarkol@google.com, Liam.Howlett@oracle.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH v13 00/13] nommu UML In-Reply-To: References: User-Agent: Wanderlust/2.15.9 (Almost Unreal) Emacs/26.3 Mule/6.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII Hello, On Mon, 10 Nov 2025 18:14:26 +0900, Christoph Hellwig wrote: > > On Sat, Nov 08, 2025 at 05:05:35PM +0900, Hajime Tazaki wrote: > > This patchset is another spin of nommu mode addition to UML. It would > > be nice to hear about your opinions on that. > > I've not seen any explanation of the use case and/or benefits anywhere > in this cover letter or the patches. Without that it's usually pretty > hard to get maintainers and reviewers excited. thank you for the comment. I tried to include this explanation in the document patch [12/13], which I copied from the text below. What is it for ? ================ - Alleviate syscall hook overhead implemented with ptrace(2) - To exercises nommu code over UML (and over KUnit) - Less dependency to host facilities the first item is for speed up, the second item is for more testing, the last item is for more extensibility in the future. Early version of this patchset included this information as well as the whole documentation, but I removed it as the versions grow. But I can revert it to the cover letter if it helps. -- Hajime