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[174.89.135.121]) by smtp.gmail.com with ESMTPSA id d75a77b69052e-4bda1fc418dsm17972111cf.12.2025.09.18.12.32.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 18 Sep 2025 12:32:38 -0700 (PDT) Date: Thu, 18 Sep 2025 15:32:36 -0400 From: Peter Xu To: "Liam R. Howlett" , Mike Rapoport , Nikita Kalyazin , Lorenzo Stoakes , David Hildenbrand , Suren Baghdasaryan , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Vlastimil Babka , Muchun Song , Hugh Dickins , Andrew Morton , James Houghton , Michal Hocko , Andrea Arcangeli , Oscar Salvador , Axel Rasmussen , Ujwal Kundur Subject: Re: [PATCH v2 1/4] mm: Introduce vm_uffd_ops API Message-ID: References: <930d8830-3d5d-496d-80d8-b716ea6446bb@amazon.com> <4czztpp7emy7gnigoa7aap2expmlnrpvhugko7q4ycfj2ikuck@v6aq7tzr6yeq> <2rkvuudmsf5tv66wya4f7m5niwnodu42owzmro5jzyc4fcep5n@lre7hir4qjli> MIME-Version: 1.0 In-Reply-To: <2rkvuudmsf5tv66wya4f7m5niwnodu42owzmro5jzyc4fcep5n@lre7hir4qjli> X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: ytu0ZGgN_Q1EvyC0ifmIkKxt44cJWvNHqQOlYKcDx_o_1758223960 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 4BED3180006 X-Stat-Signature: 6n6hqhf51m8bhi8sbafhzp6wpmcpnbdb X-HE-Tag: 1758223962-51763 X-HE-Meta: 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 53Sum8Js 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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 Thu, Sep 18, 2025 at 02:32:31PM -0400, Liam R. Howlett wrote: > I believe the location of the code that handles the folio. One would > decouple the folio processing from the mm while the other would decouple > which processing of the folio is done within the mm. > > Does that make sense? Not to me. do_fault() allows allocation and some other things (e.g. trappable), uffd_get_folio() doesn't. They're fundamentally exactly the same otherwise. -- Peter Xu