On Tue, Nov 25, 2025 at 11:58:44AM -0500, Pasha Tatashin wrote:

From: Pratyush Yadav <redacted>

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