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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?y2XXmVEFvzRRDrux/oUwjRinH0mcFJhtsZ6p2PMv0ZCvZ3jGd8xCi9hC9xWd?= =?us-ascii?Q?Km2jw9MORtsgAtHSJ+VmFaZCQqbqla4dfU2IyEUtIdErYo1FH9/JKGHO56f/?= =?us-ascii?Q?aLE/N6l3S1alGim0PKVlkVTayC8L/wW1Ydno1laBgEG4f7zw3jhbqJxkGSOF?= =?us-ascii?Q?nJdnbaHAX9/69TWOZPVxwaCjhOuZf0TZht1G5qgMqJa4UV9CnenuYrarvEkP?= =?us-ascii?Q?zVnhA4YvQemd3+UxxZwLRAX4RiyOY1RC8jyFhibTHuNNjlZGlHDReqesCrTA?= =?us-ascii?Q?f/lsMXmcD4V0BsCxg22L/mlV0xHg3EH2YEKDF2E9tET9jTni2Oamlqxe0d8N?= =?us-ascii?Q?MHjBzD9PEn3VpFz/W1zoVeAA5Z8roEiuDjeYAyT/js7hl0GUJtYnN/BfpdE4?= =?us-ascii?Q?itKEdQ4BF8HQqTBvipi65m7FsuQ1IMxJez9aFXGL4sejiiwlPwcr1aB54b5p?= =?us-ascii?Q?DY2W7n545j8q/pUtBXhqUvpzu2iyR/QgM6tFXCchxhKW7gcMoQvimcFAWvk0?= =?us-ascii?Q?HO/aKjaghExauRZacqX00rg0FfbCJW9lwDYaAgIblpXtMlWnwKQc5Kzt4V86?= =?us-ascii?Q?1z3R8ti0U7IJcYPFQj1r/grnJk/e9afOgVEdXVpTfLgxQOgMpS8ehevPUTPB?= =?us-ascii?Q?zQRRe97l/sXnlOJIYu3I+gWPkBWkbelMFaQtfyRcANpkeOUQYoM4CKsrdiw+?= =?us-ascii?Q?1Hr8xVCtlwEM9UfV8/EUQ98gUk4tV83QLmLQvGxiVHch2n4Pe3I/MhoL/0yB?= =?us-ascii?Q?P6+UMGFdWn7z3h3og+t5yz4JBXTMx1f34se+qWFOUe4Bb2NKyrA44zWb9APD?= =?us-ascii?Q?rS1/NpdiudghRvOyPdIKgk3UTW1pxcuUJbmcBslH3SQhGSPha0Sq9GFvUUmw?= =?us-ascii?Q?0UCkdHwYkYYUgM/lB55uSl5gCF6tds3Jj12kX2cPSdXUsMXqlbKOFtEoTtcS?= =?us-ascii?Q?2yjQwpkaucV/eKUFnMbv2VY9rTNgaUD30di9xI2h5XwUdhQybtzlDmKd5pCI?= =?us-ascii?Q?sVxCesbu8IoKrUcbNsB3HMfzRZYBnuEwJpMlI+f7CQoKHimSRwsAOD6qdQrI?= =?us-ascii?Q?iD4wqLFNs8j68WuuYSNfYORMQtleN4PYDy+LShq2IVK4Nj0ElpmoaDinIk8g?= =?us-ascii?Q?1rzfSQ2bRdKB/a6evWtMahdttS0JvOuNpOLyqee3R9shiPU2xzELCPG+gedU?= =?us-ascii?Q?UOGdtgYgmt4gPmKPWlxvbO9qz9dhksqsc2hJosLyIihw+sFEAsmYzjaAXo/S?= =?us-ascii?Q?NnTGO/F4+OYp4+ddUgL/jwmYsaRUZpiGsUk8WUAM1SOYvsfHfJWwSHYf8Dyj?= =?us-ascii?Q?LxUHs/I3Nx9690YGFlOkyE4zj+eMmqqZOjdTitMPjlyE69r9woYgmuIbF58j?= =?us-ascii?Q?TTv5ElRr0D5jz4Mf/FmQqcFSsfY9mvb0U7xuargjLIyWF0LFybDFM8jrRafv?= =?us-ascii?Q?ksSMV2s7sPC/owWXhe89fjY19k39h0HxsyvTdoMR+fgTpdVLkhJGlZ5ocTKM?= =?us-ascii?Q?CAM9gd3cJYiWnExqBfDqDqncX1EHuorSm22ELLihN+YKn3w/v2QfdjIeK8w/?= =?us-ascii?Q?IQvVoN8d9JfSC1C8mqwtzPr05C20bseSK/iv+WcaSxSkcYAbMtqeyA70TNFY?= =?us-ascii?Q?FIwWu+Xw3k+lRubpFZVhnRoghbuU4WHKicx2y5Vkle0WUGCdcYxQy/gphjDu?= =?us-ascii?Q?2fn0wKJdvjpG4vzOyzUsw5ZXtillNK4xSYS47M5KNLWdxbajD74DCQ7DTMZg?= =?us-ascii?Q?Ms6yL1MnaA=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: b6130edc-761f-449e-e004-08de5842b8ef X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 Jan 2026 16:41:12.9967 (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: oIkQ9gVCKzmyGnbDdk3DyM+M5xnwxv+lx2k3qBgQBl6yJFd18h3XJ4xrF7XbbDQX X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB6441 On Tue, Jan 20, 2026 at 02:11:30AM +0800, Wei Wang wrote: > Add support for the ACS (Access Control Services) Enhanced Capability, > introduced with PCIe Gen 5. These new configuration options can be > controlled via the config_acs= boot parameter. > > By default, the ACS Unclaimed Request Redirect Control (URRC) bit is > enabled if supported by the hardware (i.e., if the ACS Enhanced Capability > is present). This setting is particularly important for device passthrough > in virtualization scenarios. The memory target access bits should be set to request redirect as well. Linux's grouping logic effectively has assumed the enabled behavior forever. Jason