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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?xZgWe+fX9oBuLTxkIvtY+NhvGcJaVAQBHXqYdxbdeciF6ladgnthvOVeFoIB?= =?us-ascii?Q?pJd73s2Y0AFJOna5zvycFpRYo53+z1bSDox1wK6AEPRxBd6AUgBNyqzapR+2?= =?us-ascii?Q?FsLQhdTOsNhVliYAuZvjO6ATKVWJp8/9d2OuxTE9l9asG3egYZ6UNgzA+F/P?= =?us-ascii?Q?UT1Uh56YjuM0z5I/qjBet3rxWnUmkK+jbf/z5reXIMJmVi5Gm9rERO5PGPN8?= =?us-ascii?Q?5sme3mbGWBC5GE2oUUeFfaLAYwfPJamDv2jvMVnvWUV7MUWTdEOOndDvculr?= =?us-ascii?Q?V0B8JBB6DNItryCBR5PqtoA63AQSrcGiHatJtNG+ihJxDxriG21mFogFHfvd?= =?us-ascii?Q?DtRvQXPVUDbJt9gWYlOfSSR/DeszgYPbI3YO6SwqWiJiPkPIrty6ZlI3qYF+?= =?us-ascii?Q?QmHlyijWZZsxrx4uv548aljS/vqghjGsjdpgEmiJHo9gL1XTsHK1p/88EiC1?= =?us-ascii?Q?uDdAWNaLAW8Dpdkc3bKHD/f6z69a79eKyasOJb5AyLAtVZRuyWy64y2Pv7hQ?= =?us-ascii?Q?J0S2xgpD1AkWCMXt/R2YXwE2jFx4Sv85a2dlsGu9Vq0EGzrfCnNvH62zAjBE?= =?us-ascii?Q?8ndC+0iK0yzdtZO9agPcLsBzKRJk7vcAS29bBDmCYzDfLJ6fghNf5nYTZiTO?= =?us-ascii?Q?9oRKf+Wd4mIamtzGxnbksxFhyn3bLOHJB9/EBpqjeP5pepecndOGEO3nQCuO?= =?us-ascii?Q?F+8Wd7btO9CdCcyN8NE3A80S9Xems0RrpLsX3jaXNFl/OZq2MC7LKvb/1TUu?= =?us-ascii?Q?LZXKcxKaaDL9q+UKqe1/7NImKsziEHcwDu7FOfDGKvGP9y01CNL2wMig38t+?= =?us-ascii?Q?Cd6Rysn8lk8yUivLdiGQ5hcJSpi1HzK7fwyzqqIPZlPGVc1Keok3F2kQjftj?= =?us-ascii?Q?UYRCngBFeUpZGRmQD2sZ7JeEIMJKRlEiedS6sEwMz83KnZhAZcWx615j4z4s?= =?us-ascii?Q?wYEBAaA4ld39zylnaStRMlWnI+xK7Bu/jsiwa50n8ZMLRObqe4kC8NmniWKe?= =?us-ascii?Q?5SUQT56w8lAMpumjbPo0X6BRJ4fawBI1NiJHLLTOqkysIucj5TmEV3oKgSPP?= =?us-ascii?Q?DqGGz3suapd/f6BJy7vtCzAv8TOMSh261EqzXVwjrmZk72JZjl3vO0YyxnkB?= =?us-ascii?Q?CTV064TKwVNlaC1VpDLG8eAhT7Pq9Afg2pd4N/NFLtNKnTuswSPKi1In6n9D?= =?us-ascii?Q?f6/5aiAoU9xDOUpWcPHTzxbLsXZbL7wfrOT99TCdfhvqXXVdiNfCmptcrBF4?= =?us-ascii?Q?Oiwzapolz1VegsDNSmUXK8Nd/bpx2VGd2NgGFjWQD292nRTj3qqM/HcvDdSH?= =?us-ascii?Q?oqW00JqhDT2/Z2/8hXgqHChCBAQVSF/YzOCLsI/a2FpzrynSFli9vUSsMC+H?= =?us-ascii?Q?ce7j/h2Tg2tu4lWf3hmiqa54QRonOW5zFDdUJuuPfSuAA/vUGT86Q7Qm+G3j?= =?us-ascii?Q?YezmGPW8c1xE+uxroFjVV3sCNC710NpFCodrnKkS5gGxxufCyBPy9kJuBW6S?= =?us-ascii?Q?PL3PxfkXQzc7LXeyWm/5A0C4gNcWYBQtSLCal3Iq40RAfE9WlphkYrhtsg2c?= =?us-ascii?Q?Mjb+U4N7DJR6qn4z1UBHdVSVofHcrDZuL/df/6Ma?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: d59a3009-b84f-41c8-4730-08dd550ae63e X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 24 Feb 2025 19:39:06.0555 (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: v1ULEvtgp00eVduQ8RPW4SPrblLHeZ0K2FNFNRdq5Q9VmQwMggJtkJOxZeRA8t1R X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA0PR12MB8326 On Fri, Feb 21, 2025 at 11:42:06AM +0000, Jean-Philippe Brucker wrote: > > There is no requirement that an iommu driver implement identity, this > > is all an optimization. If it doesn't work in alot of cases can we > > just remove it? It would simplfy a lot.. > > No objection. Identity domains are useful if the use-case of virtio-iommu > is assigning devices to guest userspace, in which case you'd want to > bypass the IOMMU for the devices that are still owned by the kernel. But > VMMs have at least two alternatives to identity-mapping (BYPASS feature > and tailored topology). Since Robin pointed out a few other drivers that would like to use the domain_op lets leave it as is. Thanks, Jason