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Peter Anvin" , Jonathan Corbet , Trond Myklebust , Anna Schumaker , Mike Marshall , Martin Brandenburg , Alexander Viro , Christian Brauner , Jan Kara , James Gowans , Mike Day , linux-fsdevel@vger.kernel.org, kvm@vger.kernel.org, linux-coco@lists.linux.dev, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-doc@vger.kernel.org, linux-nfs@vger.kernel.org, devel@lists.orangefs.org, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" X-Rspamd-Queue-Id: 0D9CC4000D X-Stat-Signature: dayqcpom41pi5xfuqgjmj8uaqtj7egqk X-Rspam-User: X-Rspamd-Server: rspam06 X-HE-Tag: 1743691717-175299 X-HE-Meta: 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 EbMrMACF 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, Nov 22, 2024, Matthew Wilcox wrote: > On Fri, Nov 22, 2024 at 09:29:39AM -0800, Elliot Berman wrote: > > A few near-term features are coming to guest_memfd which make sense to > > create a built-in library. > > You haven't created a library, you've created a middle-layer. This > file primarily consists of functions which redispatch to a function > pointer. I think you'd be better off creating a library! That is, > have the consumers register their own address_space_operations and > have functions in this library which provide useful implementations. Or, go even further and move the overwhelming majority of guest_memfd code into mm/. But I suspect that will be practically infeasible, in which case I think I agree with Matthew. Either way, the Gunyah usage of the library/middle-layer needs to be included in the series. It's impossible to review the code split and APIs without seeing both KVM's usage and Gunyah's usage. E.g. this series allows __guestmem_invalidate_begin() to fail, without any explanation as to while that's legal or desirable.