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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> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <2rkvuudmsf5tv66wya4f7m5niwnodu42owzmro5jzyc4fcep5n@lre7hir4qjli> 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