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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?u2SUFQn3dMOr5Yy679SCH9KNrSJWQWP6x1sUVgdVUxdY+qz9NE3lbDQsJR2k?= =?us-ascii?Q?C1B0WEkA46z4m1+kPlspSjnDwMT09bZF+/HnLeD4HZEt0AncXNKfRAunZMxM?= =?us-ascii?Q?AGtz/Sak6Du+lTbR/7ap6ZRVD+IGlzYfMBLEjU//Co9FpJWoajud5jOqo0Lr?= =?us-ascii?Q?pkbMO737nOeNbifXhso2U1AEaYHYuxfitR7JQQTQSaY8Araiu+txwmZBM/Rq?= =?us-ascii?Q?+4FomprwGdSX+QKMHp33CGZp8746+MF6KnEOycS7dDaFMlspXh9A1JpBpLPQ?= =?us-ascii?Q?lOCmpM4gtRFYm0WvIzcvAyaHp05ST9VFPnKb6AOPdcIvH7EPOIuBhzomUmTs?= =?us-ascii?Q?ldHHCPE9k3d5Y+hwbHsMmppcvKEpHXJIZJj7sdCwLnABvwGP2yHfNcOApU51?= =?us-ascii?Q?KPbFljgKdPupNqCxjRQV4UzbM6gHZaW3lsnpvXPpBNCn9z7DkPuUCgbVKZIe?= =?us-ascii?Q?2apYgzRP0Uss43Tw1WaQOi6fkCPdYXBe53iGlaTjaVxFFfsR3lQnnuaBXEjp?= =?us-ascii?Q?5BQmKDJAlArzx2BzW0SCBMBQcMrOOTQex09NAFbToA8gCzcw3qOZ6zRIl+PA?= =?us-ascii?Q?v9N/Ivp010Ac6cqixM9qyaqS+S7UdMgsBHs9vtpHT5Wite8h7IQBQMrycpj5?= =?us-ascii?Q?AlnjAehy5SjjvdqIg6g7iKBPBQ/z4lyKnlfCujx0m0yc2QF+PfCP09G0omIQ?= =?us-ascii?Q?woYu96v0k0wo9zYOj50tMpHk5rbYGs+rdKqQcfgoaajR8QG43/PSVVd3c10L?= =?us-ascii?Q?6MiCAcUpuhkYqlUIXiQoZ5/oDKL/QmnpqXsv0tztxyRhLd/2rBWq4TMDdCmg?= =?us-ascii?Q?69Jgwt99OEPk8m8jSm3nAU9kVabk6sirdOtpQ97FbDfKdry9zOa2+gaztS7Z?= =?us-ascii?Q?oySx+RLDgpM6dSTu0ojSa3hpDDz3vFMRPMU6Ic2IA9ueeL78YqNDW8+msEqa?= =?us-ascii?Q?QmB8kNrlYch0VcqNUhW+l+LxrInmmwod+y9tE+GxSX35lRITdQK2qEqWbEH2?= =?us-ascii?Q?lWSIdnQEc5o8xVO5eBgOR0bVynYTmbVp+tgwhajL1PMexDmBermeqXy34EzY?= =?us-ascii?Q?uSl7bbESzOkQ696+5U+ni1Ddeg4vgPqINibJ8l5j51lqz2UYjxe/eRS4l99K?= =?us-ascii?Q?/iHmclmOOJ2yuPA7FBLBWOZ1wMvJBNBJ/+oTCt3hwMdMrUsBAX3oXdWYEH5/?= =?us-ascii?Q?djxwraOO9QUfKyDexSwIeQeZ/BZd4YJg47ow0nQ/rSYcOmNAJrfaF8tAJYTG?= =?us-ascii?Q?BRDgpk+L1Tob7+WZRcdyZaA3L2t6SicJf6b0ZQNIZ7vKpbf3En89nZZYM6ml?= =?us-ascii?Q?8cBP3wRV7GHXEJ4au/Fh+YBBQgCTNnLf5MGupAnr60WpT2fT6iRVtEcWQxH8?= =?us-ascii?Q?nU8b9Z9MoKRzoyhXyqUP+L3V9vRK+hSj3JIpXu1Ges777HPlwG8PQtZK36z+?= =?us-ascii?Q?uXGvwcBptMKtrgjW3HePdaVv5hEA3BM7d89gNJWEiuHSP/X6R3wU/ICkCKzL?= =?us-ascii?Q?XgQDyGujsHW5oQy/G9IF+RyuGDta5VlSMZUkbUvPASOSs7u/OUzJZY1eEbNi?= =?us-ascii?Q?0DYR0CdPc5xxVdh2N/8=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 8f335b61-3a55-4744-0ef1-08de31cf5287 X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB3613.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 02 Dec 2025 18:19:24.7203 (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: dp+S9EBhZWdihscNoAjkIlNncAx4Asl19xDSLq7a2tuGx4+Tz2WlMumq/yFLfdpV X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW3PR12MB4426 On Tue, Dec 02, 2025 at 08:36:53PM +0400, Chris Li wrote: > Jason, please correct me if I am wrong. My understanding is that not > only the device that is actively doing the DMA requires the bus number > to stay the same, I think all the parent bridge, all the way to the > root PCI host bridge, bus number must remain the same. After all, the > DMA will need to route through the parent bridges. The completions need to route back through the parent bridges, so yes you cannot do anything to disturb RID based routing in the active fabric either, with also means few changes to the subordinate bus range of any bridge are possible. Jason