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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?xV5sl24cOng/+JXfKVV+LpvyukxPrPvydPS/6gUXIv8OPVUoFbSED6nAKr6U?= =?us-ascii?Q?ig3NhsIPud/LTHR44SHYWQ5ezyu99GAzvgHT+5gItsXZ4n4P5hDrhhhSJjzw?= =?us-ascii?Q?F5RM8icwxbLQequ1f3QXcU1t6OzwjfTBFkAGnUW31B76c7+rZ4BEjcqVJcCh?= =?us-ascii?Q?MW+IjMKVBIdxC7J1XSccQEILKba4a51OhK6tFQqzJrwTR//HnvlBn42jkAxN?= =?us-ascii?Q?se5C1kljO1CS/ZYW4SM3Z5xXXoDAJw2iwm0qrBFf/fuxRrPZ/lA7P5HFCWSs?= =?us-ascii?Q?9kLaBl+Cz+KJT0WACsw/bmWlnome3lDytqxkXtekzoRY6SCb/wGxRqGByBGw?= =?us-ascii?Q?cTOnLa1O30aJS6yCxkM4tVnOhi2r1Ks/p593fjRMUedZoiqesmKs0PuhgXY/?= =?us-ascii?Q?TlNQ5ST9ohavmeStTg0C5P8gomlqmEGmbTx8GrR3pXt/YyCdtMNKjgsB3U2a?= =?us-ascii?Q?Y/cySKJqYmPgx1VItcpP3WxnRv3rnyZgqiFHV9jtb/aaRM+cXFeJ2m/Iicb9?= =?us-ascii?Q?eSeQHjcgf8Ho6q3zbh64P1dJMKMn8velA5hwJcsjSVtpKfossGjy6tQuH7Lp?= =?us-ascii?Q?e2RPBeFOHzbkUjYEGRjr6g5n+KEMRLdc5VKr0TgejbNsfbZBkPhRzfTNASq9?= =?us-ascii?Q?ZiLWAOutMFSXW/gIJXfxL8XaGQZ3eDhf9zImq2cUj2/4vM/yUfC7DK4uOASw?= =?us-ascii?Q?UBovpc9VHielk5AJfJbvEJS0zLWGhi2g8Opvr3TUeVLgRJOIWHny72a8Vgfh?= =?us-ascii?Q?VPDFJHvBXcYLYg92JlPKFWcTAqzoDg+o6f9o2OpyI1TZxegrvWYzjhsUuueL?= =?us-ascii?Q?oYNJNup/qOt6iN1wvV3e+zZEHHykYKncqUflCs1YIfz1MS/ilkI+SbZ+iZna?= =?us-ascii?Q?Ubh860vrgetZeYadBmidAG1oQ71QOQS5kdopI09ira3HzCk9We+QSHdX/nSm?= =?us-ascii?Q?Uul62+VSfo4w8K3R+lj1oUYUvtn6GiKzGV9gvouWeVszdlQrJAO4BfnWWg1D?= =?us-ascii?Q?C1wRBuzpAlrvMESJ39YwxXCUawHaHf2e/6Hql5Xh3eoMtlcR1sJRu6EH6Fhy?= =?us-ascii?Q?HcYnOAI3zXHd3MiFZJsoePbtGGxrusaJd4S49TQKAEMGahwiy812+n+DfrHx?= =?us-ascii?Q?XWevVpwJzTwcFDX1SE401Bcu4faYOgBZ73RtEzledDBSQ6KX8hVma02Wlo41?= =?us-ascii?Q?C/x+v6qlKtOXXQ12pFspnTXiaN8uLX4w1yfD8KEm9yRkzstgp1TQbLprv/pi?= =?us-ascii?Q?exScVHGVpT6/Qs1f9EsLKL3srJvW6qgSnzWJCshVHONBz4206BpmNGQV8sBb?= =?us-ascii?Q?JZR01urlOqkuYrZdaiZYXXNXOpm3ey/xo5u92sY4q6eOh+psBzE3USq4+yU7?= =?us-ascii?Q?wtBq/av3ZsecegOOAXwvop40IWxNfBV5S1E8W+gS6MENOvwcreVlsDndmPuu?= =?us-ascii?Q?f7gRRoNA3lpA1qvVQk/pQUDimVo78OJVozp8gwY3/KwKALfH0vlcbSt4S1fI?= =?us-ascii?Q?8b/GYswBpPg1b6UxEXFKd36fHveuP4/xLRHIsVvSwFzdu9qDEqyDpCScsaDP?= =?us-ascii?Q?aTTNmYE9tyXQkzLgjVheELag0z+tyfHmzkwUIZV1hYljypL1MvKvv4o0PsAJ?= =?us-ascii?Q?lWb7nSzA+12aiBGKlcBUDLl1iOhxP/eU96hmpK+6BuUgztKNUYmJ9J9u0f57?= =?us-ascii?Q?xpbQfmtrnx4ZsHJKvTAiDs/ocsQ3wd8gd54iwLC5tw4EedA5?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: cfa9b40b-c6ce-401b-5f7c-08df0a9d999a X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 04 Sep 2026 16:00:11.5213 (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: rWdojgZNSskNuyGNN+ISFbG6xbEC5yT8H16EoHvt4xWi+RHq5Wshm8JQxguaRiwy X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH8PR12MB6772 On Wed, Sep 02, 2026 at 07:34:49PM -0700, Logan Odell wrote: > We're including maintainers from all subsystems that currently is or > will be expected to participate in live update to ensure alignment on > the path forward for compatibility. > > Currently, Live Update Orchestrator (LUO) and its file handlers rely on > monolithic compatibility strings (such as "luo-v5" and "memfd-v1") to > validate ABI compatibility across kexec live updates. Any modification > to serialized structures requires bumping the version string, which > strictly breaks compatibility between adjacent kernels even when changes > are additive, backwards-compatible, or optional. That was the intention, I aruged strongly that upstream does not want to maintain a CSP matrix of endless kernel version combinations. That is far too much work to push on maintainers. Upstream would do much less, maybe only same-version, depending. > This RFC series transitions LUO and subsystem file handlers to use > granular feature bitmasks instead of compatibility strings. We replace > the compatibility string with a header structure that includes some > reserved space to define the features that are included after the > feature. The compatability string is only a small part of it, you also need a serializing ABI that can handle some random mixmash of these features. Ie the various TLV schemes that were all proposed. What is the plan here? Jason