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Peter Anvin" , Hugh Dickins , Ingo Molnar , Jacob Pan , James Houghton , Jan Kara , Jason Gunthorpe , Jianxiong Gao , Joerg Roedel , Joey Gouly , John Starks , Jonathan Corbet , Justin Stitt , Kevin Tian , Lorenzo Stoakes , Marc Zyngier , Michael Roth , Mike Rapoport , Nathan Chancellor , Nick Desaulniers , Nicolin Chen , Oliver Upton , Paolo Bonzini , Pratyush Yadav , Randy Dunlap , Robin Murphy , Samiullah Khawaja , Sean Christopherson , Shuah Khan , Steffen Eiden , Steven Price , Suzuki K Poulose , Tarun Sahu , Thomas Gleixner , Tom Lendacky , Tycho Andersen , Vishal Annapurve , Vlastimil Babka , Will Deacon , Xu Yilun , Yan Zhao , Zenghui Yu , x86@kernel.org, Shuah Khan , Fuad Tabba Cc: kvm@vger.kernel.org, linux-doc@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, llvm@lists.linux.dev, Ackerley Tng Subject: Re: [PATCH RFC v2 00/50] guest_memfd alternative providers In-Reply-To: <20261022-gmem-alternative-providers-v2-0-5dd1dc6c660a@google.com> References: <20261022-gmem-alternative-providers-v2-0-5dd1dc6c660a@google.com> Date: Thu, 29 Oct 2026 11:22:59 +0530 Message-ID: X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 3BA7280003 X-Stat-Signature: mf3fbcc5icc9gnp76pfohc7fdbzze5bm X-Spam-Status: No, score=-5.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_PASS,SPF_PASS autolearn=no autolearn_force=no version=4.0.1 X-Rspam-User: X-HE-Tag: 1793253204-919360 X-HE-Meta: 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 HFeHdSCh 6b0zx38XwKss3yx6+Vh2/Kqzac+6baPhY//cwZ8g9yUVeuRsONX7EdokHAnzAveg8rS5l5hI2JNX/Jrvb2KM5TXSrIxy6wqGTz/z45qf1A+LQVseN9oTpKv6aYEDJpgG7+Sm1Mlg8hGofnAJxrkzqHTWY+wxMRomRIekAg3ekfH6mnMuB0osDr6wtzxrgzf4njWRU/nwrnwl5bLuwlLmZsNLqnCVGJujz7tEnHGCXiSj0rUKLZizrZ/msS2nwqwLdNaGNXtpGJx2zXXeOJdlZLO7iRxKV7yOhqvBCy1OTRcUcdLatG+Foi4cPZF63S0kzcx1Xy/X/o2a+RvK90F2ckb0/iQJi/YWCovJW581Yx7QVjKgiSMD//9HRPC9noSYGjzTYw5Reb+vZPIscuSk/KJH9G4Z9j+e3iaBOfkNuRcgreCBS6DBDJlV6c+Gk0ufDwpjQ7b/UY8GlwXUfP6rXgr56tA== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 Ackerley Tng via B4 Relay writes: > Here's RFC v2 of guest_memfd alternative providers, continuing from "Allow > guest_memfd to be created using a resource (pool) fd", which I'm considering > RFC v1. > [ ... 138 lines skipped ... ] > > Aneesh, thanks for your series [4], I haven't got a chance to look at it yet. I > will before I continue this prototype for IOMMU. I want to get feedback on this > part first. > I am looking at rebasing my series on top of this one. One detail we need to finalize is memory access through resource_fd. For a VFIO fd, I believe we want to continue allowing access through that fd. This means allowing read/write/mmap/ioctl, with the VFIO subsystem accessors checking whether the memory is host-accessible before accessing private PFNs [1]. My series denies mmap through the guest_memfd fd. https://lore.kernel.org/all/yq5a1p9qxmqg.fsf@kernel.org -aneesh