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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?chQPQAtOXF6kxE9ZI1r+3az383CDuD20912scnpFk3fbb46WA2FlJxlnZk0H?= =?us-ascii?Q?UXpjj/IsICk6DrNJC4+3VeE3p+MsIjzOkh6W8K8VNmPI+RnYn5mAnKWyvcdl?= =?us-ascii?Q?HmcK3h90ETOUW5R9DjxWesrGP+t38j4ekt/ky1QhY+JzE0GlKFO2VF3rXiUD?= =?us-ascii?Q?Rzt//FS8J5Aco1l1uuKUm7lOtI/A4ROwe4dF1Yvmb8Cqg1zJdRHY3ng1NUja?= =?us-ascii?Q?EaNaeVX+EkcANFWerMfb2+G5HHDuAt3ISfKRR/vs6HhmGmiy5/G8nOi33BkL?= =?us-ascii?Q?vElwr1/wF4CQ917K8lWwjhk9x+kTYiQmN0Z8vf5iMrKTA+T1/ku8VuVfVMdo?= =?us-ascii?Q?kprhZBfjlhKN0GKZSDjNZ1N9mbAZqV5VADYgyfcOSCuDNGu1MIJmAXzVfbUi?= =?us-ascii?Q?KqMRtVi0AgoO7AmXEGF/2oakX8ACZgxOIA6VNE85SECALQgvGENK9G7MjS6i?= =?us-ascii?Q?eZ3yQSP9z4Hsl8mz9dLwErdFFqSOD960Sf8GDdPELVSOtf24jvTwnxcsn3mz?= =?us-ascii?Q?Z7uY2amnpW10SWJflrlL4bFSZINaDbFSgWYsisVr9T+4Lfto35sKyASiDclO?= =?us-ascii?Q?Hn8CvU1u2ap8rv0019sdW41a0ixHfAKDQsxH91ChtmLyHUlsJOrrThqmQG14?= =?us-ascii?Q?OTIHCjYNjyQ/SkjCLAt/xzcjTMqIDQro8yZPy8jyGFI1qGfBb5gxtj/NZtEP?= =?us-ascii?Q?kc/+4az5KdQaY3SGnmhqzVZSSgvZfm4/e6y+8s38RvPdg3I0R+17JZBDrgOb?= =?us-ascii?Q?pIr7pKPtIypJd+TWb3Yit1YJwS8nRJQK8zeVLB8fbsPKZ8EbOkObK585pK/t?= =?us-ascii?Q?lF7daEbKWC5hIJ3hvvFtmuuS4CuANs04MzHNAPFURWiaGj5g+gzu+cbJSwhp?= =?us-ascii?Q?AFo4biTCM1oDTlx56QsKSt7H57DxHmFXiddX8W6OEwiS0p4/avg6kkHu3trr?= =?us-ascii?Q?QE5z3gFvb0s2VRJp96wWUHfGgKtZsycLLTAIBCtc1wHDMKz5pAbyrWVKWDTt?= =?us-ascii?Q?u2brxcbsuE3x2GZC6TM5LH/+NcEvHrGFCUIrrep9icIDqoBfnjvRrCIloXiS?= =?us-ascii?Q?SkhGLa18zRg1+gdDDdoc8JZaT2KrhVj1OAl3UzyF4R5ByVtVu9xfjWORaIGQ?= =?us-ascii?Q?m8qP9zJjO/ofIDSawrXKIqWVRufFiFRWrwkbvwop3S8rDFBdXFOfTFpaMqr5?= =?us-ascii?Q?zaILCzrrINJe9rpJxqN7vYOUcewhQbckYHDzzxx8jMXzjkKsE5EnIqCzHWu8?= =?us-ascii?Q?I1qIq6F8Cy2dAh8wniI7HPYC04bfxYRLnO5EQu3CudksIGcsgOZ4fv2cn2dA?= =?us-ascii?Q?9SeIYjvMiKBlIGDuSvSjx/JQi7juuLlNkj+T5twXKes8ksFnuxUqkqPeCJ6E?= =?us-ascii?Q?SvE/4H2WQUoFpkN7sUOq86ObtoN+XEc/YROOK5vVtnk1nYYBuCmx4UpR4YeY?= =?us-ascii?Q?CtguVzhTgJftXcOB9wLsgpDRsnYFpUBg+m3bGEKZEsLTV8oc29mJEDJsCcF5?= =?us-ascii?Q?8LTiowlVRpM3uRj7nUIBZCBCBja1JtMEIluYuBVLFphuiKcTxkNMfOaYJAKt?= =?us-ascii?Q?CFbzbqj3SVd0scDWY1/rfVFETkWtzVv+cCb+Uec/yGk4uieJEniuXwubhULl?= =?us-ascii?Q?15Nx4FHV5KxBkORWVV5WlC6T55Dg8VFTAs3gWOfRKPumfZzYjz6hRnxoTpQE?= =?us-ascii?Q?vVdgzRIbmSjHTu5G8o46Gv9WOjaIOv95dnQqvGhjIczc1nx4MX8nYGVVM7J8?= =?us-ascii?Q?q/lMKMrQ3g=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: a0be14f9-b8cf-449d-fba4-08de4e1e27a0 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 07 Jan 2026 18:54:15.6317 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: PzQZIBZ75FJVCpk5+uu6XopuxmPdi1NBGEr4MDv4QWAT+q526gG7qaBqjI1rdQed X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS2PR12MB9591 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