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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?Jf/mDFnpVulJsOhIB030JJYkWXYPYqiy1QDAPg5IHXpk9qnJHa8D9N6cGhBu?= =?us-ascii?Q?PgjB4jLjAAdSTpu4URlOKGRmqmFm76lBcPZkgWlP03u5aNWsYqCLM5G7MlDp?= =?us-ascii?Q?NlRJM8q4G2ddIY4i4RQisqaFW46ckd90bwR2EU8WIeDeD8TfNtM34T8LJr9O?= =?us-ascii?Q?mKt2V2FxtPfGhytg/bFlzptqOrAznUFtUHZsnfM6pVljEITR4JyXdfhoMAl4?= =?us-ascii?Q?MqLvsLyirqvQDen3VVaQzdMyOI0NfljlUwO0ZmBYsDEARim8nBvJ6UBsdmue?= =?us-ascii?Q?u6hlEBJZ8tHBDa031Zca0tNoQsiRDju47pfebfDroPeefvB8TAtMDkN1SnOR?= =?us-ascii?Q?xq51U0/RWGZCQdGQq81gQri5fCW9qfRCB2pMFxCHKT543ydcurupgKgjxEMs?= =?us-ascii?Q?RTWTnQUsLyuhhmimVr/X9KPEqih2mtvHWKZbbbeKYl0HeI64iszFLfDelvKo?= =?us-ascii?Q?ebrCevprgicF93hPOGQtNgGn0frXDjXK6+nJwaqXzQ5krxcQRfegZLmNshPF?= =?us-ascii?Q?PZhVJXpGaXUqKbmMqGLVFsRK3ys16W3vSoysrMHkJqnhNyv/wbLtZ0picv+M?= =?us-ascii?Q?kifP1sbZEnixBbkQz0gcn+8EWc585hK5jvW8bME1iQ/9+5nXmInW2vY97UCm?= =?us-ascii?Q?QDk3ILnPKCwET8d4qHwAAfuSAnyERB998wNAB2Y4DxDFJPYZlR6PEyKaweR6?= =?us-ascii?Q?9XN9Bqvw8+Ep8Y3jaww54MqZBkTLmRYTgRgHdPZNvl0ReNmgBNOuKdFyCy+k?= =?us-ascii?Q?dgmlcPR8BwioyMiF+cITantPddlXDXdZ8LVZzbHeJOp4EDVp4gglSVKX3L0i?= =?us-ascii?Q?ZbNmYpp4Zbvkbj37W08bsdDu3WApUwZx4xqQpoL4Rn00tCNUDavOYMHb+3iU?= =?us-ascii?Q?XKElyy5mbS+RGU4LBIMnr3Bn3sL2Kni5HLKIbtWpuX2vnS24HMtBwkYspNmj?= =?us-ascii?Q?X6SXoMEFJQMoam+TQG8j1OTZSMhW+iqhpz7bM2KTAKOpQRJR0Blww4GiJ42V?= =?us-ascii?Q?pElSMVLZaYFB2w0GxJCwENH91igBaxWvtNtZF3kOAl5yjgVqjWKz48Zin24q?= =?us-ascii?Q?GdCFjsVUGJLpQJa2sWgt+TCqudSbW1Be716hao9cZC9oxbUGpJXZKutVtyA5?= =?us-ascii?Q?bIYAuhK7yN/gwuMli01fX6dWfMXCCo1nGkK1PykUOTKbupiLPaMJ1/57Y/Z1?= =?us-ascii?Q?v/NGD1hma+KlQvAfH4ci39MJzis+23jsebKS2oXxeInnwFC5NsVy3+RntAll?= =?us-ascii?Q?Twvukuff7bKIRCcMpQ/T6QbSqWvJAIeeIJ1kTGPKY1mw608KZTjslY0DvK6U?= =?us-ascii?Q?O1kdt95XwRo8S0wA0vT6QYynP+IUgmgjfYC6+NHfxwNapkvw3QtLDHxqqxwB?= =?us-ascii?Q?aRE8kScI3HC7MccaVEMRrixHdpadl6DcLEvs7FVue+dokeKS9Z4jAtGZglv6?= =?us-ascii?Q?BxZQa96jmRZ9FCFdXePxne1FzV0ptRXD5dzfXy85qImlY0eWOKuIxujTOoqu?= =?us-ascii?Q?dWW/VnqRb67oQgxowIJpr+3VD3VX6WOxkICSWjnMOZp4jJctpSQbnJm8dK+R?= =?us-ascii?Q?6FKCd5I0i1pMEdxHhp8j3DiNWNn4AseTSHTC9AIu?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: fe020ca4-5539-4eba-1d2c-08de10ada4b4 X-MS-Exchange-CrossTenant-AuthSource: DM4PR12MB6373.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 21 Oct 2025 14:25:11.5385 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 7o714qHcigpv7Y2qHl3z16xE4N8Gyhwz2D+5YmzGxyHoQlHIoy0mZgonLW+vWNe2vlaQERQVOBK7zXTk2MZDmA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ2PR12MB8941 On Tue, Oct 21, 2025 at 04:15:00PM +0200, Borislav Petkov wrote: > On Tue, Oct 21, 2025 at 09:37:45AM -0400, Yazen Ghannam wrote: > > It's correct that one of the root devices will be on bus 0x0. But that > > device will be part of AMD node 0. So we still need to pick a root > > device for the other, if any, AMD nodes in the system. > > > > For example, a system with 2 AMD nodes could have this: > > Node 0 : 0x00 0x07 0x0e 0x15 > > Node 1 : 0x1c 0x23 0x2a 0x31 > > Aha, so next question: isn't there a way to figure out which is the *first* > PCI bus of a AMD node? My gut feeling tells me there should be some info > somewhere which we can use... > Yep, that was one of the goals of the recent rework. I thought the DF register held that info, but I was mistaken. I haven't been able to find anything else. We can keep looking, but I wanted to send out this patch as a fix in the meantime. Thanks, Yazen