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Thu, 01 Oct 2026 07:17:44 -0700 (PDT) Received: from jgg by wakko with local (Exim 4.97) (envelope-from ) id 1xCHbT-0000000EHOj-0Nin; Thu, 01 Oct 2026 11:17:43 -0300 Date: Thu, 1 Oct 2026 11:17:43 -0300 From: Jason Gunthorpe To: David Woodhouse Cc: ackerleytng@google.com, Hugh Dickins , Baolin Wang , Andrew Morton , Sean Christopherson , Paolo Bonzini , David Hildenbrand , Jonathan Corbet , Shuah Khan , Randy Dunlap , Shuah Khan , vannapurve@google.com, erdemaktas@google.com, jxgao@google.com, rientjes@google.com, fvdl@google.com, jthoughton@google.com, tarunsahu@google.com, pratyush@kernel.org, fuad.tabba@linux.dev, Gregory Price , yan.y.zhao@intel.com, michael.roth@amd.com, suzuki.poulose@arm.com, Christian Brauner , Nicolin Chen , Xu Yilun , aik@amd.com, aneesh.kumar@kernel.org, Vlastimil Babka , Fred Griffoul , Connor Williamson , kernel-team@android.com, kernel-team@meta.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, kvm@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org Subject: Re: [PATCH RFC 01/17] mm: shmem: Implement guest_memfd provider operations for tmpfs Message-ID: <20261001141743.GB3019323@ziepe.ca> References: <20260925-gmem-tmpfs-backend-v1-0-d36159822d18@google.com> <20260925-gmem-tmpfs-backend-v1-1-d36159822d18@google.com> <9292b27b8f48c515bee3246cf3b3a60762302186.camel@infradead.org> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <9292b27b8f48c515bee3246cf3b3a60762302186.camel@infradead.org> On Thu, Oct 01, 2026 at 02:07:40PM +0100, David Woodhouse wrote: > The *consumers* of this memory provider API will include KVM/guestmemfd > and IOMMUFD. The latter *might* be through masquerading as dmabuf, or > IOMMUFD might treat memory providers as a first class citizen and be > taught to consume them directly. If we are reinventing a dmabuf improved for these use cases then lets just use it directly. It would be nice if it could handle MMIO and "cachable MMIO" as well. Jason