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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?31UWMvHSpfQlxvSESav7zKr0IW54X/gBIjzorW9MwD6MxJwUODWvXYLFwWjh?= =?us-ascii?Q?2f1weLP3+Qw86UvJGNIGmVJWPO8aMxO+/8YhcANLp+cLvSlZOOzDOm4go3r4?= =?us-ascii?Q?zr+Ibrt55QBbUYtn8gEq4yV2dF8nemKh7PaZJmx48iW7KBjTlExK1uhIq4RD?= =?us-ascii?Q?UmgT3fdgifZUDqyz0wGrPhlJueugO/MhCnTIB2zjROy8ZfuRsJ3O8ijb5iUy?= =?us-ascii?Q?tAzDPXRSwLeFL0izEg5CKOCVIgq4LhybEG3QLH82lBuRlpDNvlCaXqtq79NK?= =?us-ascii?Q?D4EcdmgrSaNnUGsSaOewnZU3SLlGPPbG/TwfQxrGK0Jp1p2AQPSPu0JMCVKV?= =?us-ascii?Q?7UbBuiu8I3MfSsxU0MVeNcmOhsWZBB8qz+EoNoD/upfX3uO5hE4I+nQcjBy1?= =?us-ascii?Q?wYREmBHaVa5zRDobacplc6WQy/p8GIzXuj5VJOteVa4aqTU8pmg9AfSZ6W7m?= =?us-ascii?Q?IqIyfPn2NRAINE7MTyrCXJmd9cxOmcDd3DvZYzR2ftq3H1tT3FO9fnM+YglX?= =?us-ascii?Q?0OjRD80+VaCFn86VBAfzt2niiOf9IBO62Dvky4EioMEaFUYh+EwHprQZIX2b?= =?us-ascii?Q?OGkPX3ttbP1hC9Fm7kutp8Jerk9HYsCcO+YXdcAOMEkZMC5fNV1RRMjybnQY?= =?us-ascii?Q?89JEn82qk592nc1sqC6sZliNhxyv2Vuk9YWhD/cJPQ1x7iBM5eZ8hRp4OkVG?= =?us-ascii?Q?4lDXq6c1SQ7MiJ46cGHv6zjW33n2dVGIN5HDfIvDwJMTPOsNXYIeAfvZKWth?= =?us-ascii?Q?ZF2UsVs2OYgK9kcbNvFCLM3sjbYKI9288W4/IdkP3e7tATk5ypGa73R9Z5c9?= =?us-ascii?Q?jj0q6sKPFbfsUoiJpWsunDyj+G+Go15NFf5RYM/Vfa9wm9QVrX69aYtxBB/N?= =?us-ascii?Q?lIlthRKZ36MnROmkeMbTREm+Hp2bXxZxPCBGu3t8xg87OlKpVfCVvsgqN6gj?= =?us-ascii?Q?OfbhtikX7RZ6oE9YLfcJ19lHJ4Yn4pSDAJ8/79PWxHEkKSnOO55AxweBTQeH?= =?us-ascii?Q?+g72/CFJdE7/jD1lpnS0T2Hhk/8xTiKOoOg7wj69y7RhOyBZcTAr20wW/4zB?= =?us-ascii?Q?xnyBCntojCmHEQBkgMMm61ojFCceXpBh2I/gvLtqrDtmc5ITAFHXTp1jq0Ve?= =?us-ascii?Q?uEGWKWetagozgK4yn29H1wIkOBMKTgOO7aKcY3a91iDit0apOd7SL7M/H5AQ?= =?us-ascii?Q?xZI+MXoy/az3EmBANGl/6MtNS71W+feKMApNPH35bXdaITJUc0n9SJnAeO3j?= =?us-ascii?Q?/TdkAGxvu4+c1bVpHuOb6YMnp8yzKkD2t8IgnKNEeg0/4R6gCHXUPZg31NUX?= =?us-ascii?Q?ILbbqwcDAyQOAJ4jz7l7Zw1kTOR5kc4rVEHXNkJSECZZHwItWz3JQfZgwt3I?= =?us-ascii?Q?eP7/jJZRZOp2uL9R0OaoapJ8eZpSss8SvOWoKDtLwsguWuhbJzHe2GieI8EB?= =?us-ascii?Q?GapzCKoZALgaWQAWOTUoFq1xOC0PweLs9rY4Icl5qUnrEBpZeNv+XcmaEMCz?= =?us-ascii?Q?aop2RaiyN5fVyxe1SLxXYu01a7GOx+8/jalBtDubHtQ6utc5fOXtbhf2xDog?= =?us-ascii?Q?X5gQFebCgT0ydJgEchv4rjLWF4ohE/2RvBp1orgh?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 378f08f2-d989-400e-b963-08dbbac322d6 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 21 Sep 2023 16:52:27.0929 (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: qtFjSwRKPgkJCeH5/N3jveim/1qU0jmKdlny9rsvhK4296N1papTQH7u5Jafaky+ X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA0PR12MB8302 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Thu, Sep 21, 2023 at 10:43:50AM -0600, Alex Williamson wrote: > > With that code in place a legacy driver in the guest has the look and > > feel as if having a transitional device with legacy support for both its > > control and data path flows. > > Why do we need to enable a "legacy" driver in the guest? The very name > suggests there's an alternative driver that perhaps doesn't require > this I/O BAR. Why don't we just require the non-legacy driver in the > guest rather than increase our maintenance burden? Thanks, It was my reaction also. Apparently there is a big deployed base of people using old guest VMs with old drivers and they do not want to update their VMs. It is the same basic reason why qemu supports all those weird old machine types and HW emulations. The desire is to support these old devices so that old VMs can work unchanged. Jason