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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 Tue, Nov 25, 2025 at 11:58:44AM -0500, Pasha Tatashin wrote: > From: Pratyush Yadav > > The ability to preserve a memfd allows userspace to use KHO and LUO to > transfer its memory contents to the next kernel. This is useful in many > ways. For one, it can be used with IOMMUFD as the backing store for > IOMMU page tables. Preserving IOMMUFD is essential for performing a > hypervisor live update with passthrough devices. memfd support provides > the first building block for making that possible. I would lead with the use of memfd to back the guest memory pages for use with KVM :) Jason