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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?M89JRlzUgKQul31cjSqKyNSvna+li1xICjLZ6cg7DetDpZM6HHDmPM3Ku5QU?= =?us-ascii?Q?vMdZtiILW42kx0c2aQwxtbE5wmCcoGoalxRWPvcrE0DWhbmqpSKNvcfPtwx9?= =?us-ascii?Q?WNtHShA+8ymHpFOJ5M9urK3HSeYobSzZrii/k7+LcReUizyeKYzoDPqOr6vQ?= =?us-ascii?Q?6Us9sDGSgko9wire6JwEByxSKJK3Gif19LMohpEfIr7WpAJVKGUWgLga/hez?= =?us-ascii?Q?p99lBldO5lWBv+s50dz7cotY7wIMrlymi2RtvYoWIu5CZFBxmeEIt3NBzVhp?= =?us-ascii?Q?yD3eAVaAuW35M4goq4Lbsbo8zrdVUqRGZVgeOBJjVw8hakUharQ+3dIaGXRP?= =?us-ascii?Q?IQvpSvQo9KXNPTwcnPPiLoMhPtVbc6EryYPur8M8/+EJj3CRYmDAdhnRAH80?= =?us-ascii?Q?L5Wy45whywFyCQ/K6wmpIlyYWK5euZjuvN69lnVJBUa89HeOJi/WmmBq0L/6?= =?us-ascii?Q?X8+R3xtT2/H0Q76XQ8JwmrlblgbEB5h6T8BArk5QNFi3DSDOI010IFhjGq8M?= =?us-ascii?Q?KUhUEoAjpQZyt73hrMt8X6/8CCD4B3HpgYC2MujnMoNhVGmzJkm7YTQQD/t3?= =?us-ascii?Q?KKP8GcU2LYEU6Dm+8Z1+59Vv8aPefAnOXs/bBXS9yb3/HWtXrXJ0FICCplzb?= =?us-ascii?Q?fubhANsNprmt5RPDaZrlItFmlp6MAAtabh/W6Adnf3bXQ9ABFJaL8fgxqc3J?= =?us-ascii?Q?+5sbnUVXF/7VkWRFUxKTvpT1P62pwCVB6NgRebUFtbWhA/EqeBJgVHB3Y+CE?= =?us-ascii?Q?rOnh9wMMz6mNmRj//IYB85h29Qh7qDI/pulsV0agHG6PqxYCIygYJuVnSSpk?= =?us-ascii?Q?b2p72ZW9lbFQd/6u4HgBozo0Ho6efPfyFDTYa49AhNSGfQ1Uhr/oPgV/vJXy?= =?us-ascii?Q?0zVqTNwYJctHtne5ftdlK1ejGsYp16ufm5QS/5nYx4kcEngbuAfTf9nkLhVA?= =?us-ascii?Q?roNrzaGagrHvchiOoZkg1E99zroYKpZ0vQEObj/Uwx0tj6T0i+nvGssCmFmw?= =?us-ascii?Q?Wx65ZZkfZMsgLUeIn0LT+GImiWJk4kQoPFLxCh1gX9idPG5Qlpd+15sJIrfC?= =?us-ascii?Q?H1Ok/m/hky7gjTFEawdkTb7PERXyooeVSkOSMk51nkP8UVlympd2QSsHaTe9?= =?us-ascii?Q?7JSh+NLsPiLz1fa6NEjuyKi9BTw8+lSdZ0u6TrfhZF1/mRrD7CGSWfQTSBVY?= =?us-ascii?Q?ziO7b+igok7Zuk+YTRkvQTaNum9Dfj65c6LXmwKwKHupUU1hH6eSQz5Fp1ag?= =?us-ascii?Q?FN5kLkBnDkcNdmkC0k5cIyo4dt8Uw06IhA6c1bhwIP2yX3mbdcLbBwG14rWb?= =?us-ascii?Q?uESkyk2MOHEmVGB0SD7z90qQmowTqGDnIf1GrKNiqZrA6t57FF48qVmCL2JA?= =?us-ascii?Q?j1rN8sHm5a/OwHZI7axBpLS1RsAQ+9H87hhqQD8+uknd1bFwyID/L4kWaY4B?= =?us-ascii?Q?gZUYVUi1VZL+bEKLZggBi2oAJLXrvXfwpdjpyQ8i9rFTyJTib5Z7oN6nDZlW?= =?us-ascii?Q?gXOa2romdS2MlZTCXs5Z4Z7DOZ5UwrM80oWtwBpNsSnPXX3GSPVJDHZJkGpD?= =?us-ascii?Q?C/KYiXBl3yQ3OY6VO1JXt+PKBt8ruQt/tITqLNtxjfCCL4isfXjZKg0NsGVy?= =?us-ascii?Q?qPwH2PRrwFl5eYvdsCDXU2hvX7KXCrsjhj0SHkqj1/ws2u5YiKmYDH1xQSE0?= =?us-ascii?Q?mr7lmAHUYXm/pBOXwmkW60Ut5g3lKhiqhprCFHlyC7w7wa1lYh8hnQQPK2KT?= =?us-ascii?Q?MG2s7UtVhA=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 7afdd56f-a1f8-44aa-4d33-08defa50eec8 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 14 Aug 2026 22:11:04.5514 (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: KaBw8o2/goyb1kwIouhbrp14yafF9nUJVB14Q6f2PB6y2l68WL8Sd45bMQs31sll X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH2PR12MB4232 On Fri, Aug 14, 2026 at 06:56:05PM +0000, Dmitry Malkin wrote: > Hi Jason, > > > If viommu should support multi-device groups, I'm not sure. I want to > > know why you even have multi-device groups in the first place because > > that is not normal at all. > > That is because of the 'pci=config_acs' kernel command-line > parameter. This causes the kernel to create a single IOMMU group > containing multiple PCIe devices, including the bridge (PCIe Root > Port). Don't use it that way? If this is an nvidia system you should talk to your support team. Jason