On Fri, 15 Nov 2024 11:48:55 -0600 Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote: > The "BUS0" nomenclature seems heavily embedded in the vmd driver but > is really a misnomer. Maybe that reflects similar terminology in an > internal spec? Any hard-wiring of bus numbers reflects a property of > the way a *Root Port* works, so using the right name will make this > easier to understand, especially since there are other Root Ports with > the same hard wiring. Hi Bjorn, It is named as BUS_0 and BUS_1 because it refers to kernel's pci_create_root_bus()`, we simplified it for better code wrapping. Looks like it confuses you, do you like ROOT_BUS0 and ROOT_BUS1 better? I don't see better fit than "root bus" because we are creating new root buses accordingly. Internally, it is called as "VMD domain" and each VMD Domain is presented as separate pci root bus. The original naming is presented in the sysfs links: - "domain" -> root bus 0 = "domain1" -> root bus 1 i.e: domain -> pci10000:e0/pci_bus/10000:e0 domain1 -> pci10000:e1/pci_bus/10000:e1 Thanks, Mariusz