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Howlett" , Nikita Kalyazin , Lorenzo Stoakes , Suren Baghdasaryan , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Vlastimil Babka , Muchun Song , Mike Rapoport , Hugh Dickins , Andrew Morton , James Houghton , Michal Hocko , David Hildenbrand , Andrea Arcangeli , Oscar Salvador , Axel Rasmussen , Ujwal Kundur Subject: Re: [PATCH v2 1/4] mm: Introduce vm_uffd_ops API Message-ID: References: <20250627154655.2085903-1-peterx@redhat.com> <20250627154655.2085903-2-peterx@redhat.com> <982f4f94-f0bf-45dd-9003-081b76e57027@lucifer.local> 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: On Wed, Jul 02, 2025 at 05:24:02PM -0400, Liam R. Howlett wrote: > That's because the entry point is from a function pointer, so [3] won't > help at all. > > It is recreating the situation that existed for the vma through the > vm_ops in mmap, but for uffd. And at a lower level (page tables). I do not > want to relive that experience. > > We are not doing this. It is for the benefit of everyone that we are > not doing this. Is the vma issue about "allowing vma->vm_flags to be modified anywhere" issue? Or is there a pointer to the issue being discussed if not? > > We need to find another way. Could you suggest something? The minimum goal is to allow guest-memfd support minor faults. Thanks, -- Peter Xu