On Tue, Aug 05, 2025 at 10:41:03PM +0800, Ethan Zhao wrote: > > > My understanding, iommu has no logic yet to handle the egress control > > > vector configuration case, > > > > We don't support it at all. If some FW leaves it configured then it > > will work at the PCI level but Linux has no awarness of what it is > > doing. > > > > Arguably Linux should disable it on boot, but we don't.. > linux tool like setpci could access PCIe configuration raw data, so > does to the ACS control bits. that is boring. Any change to ACS after boot is "not supported" - iommu groups are one time only using boot config only. If someone wants to customize ACS they need to use the new config_acs kernel parameter. > > > The static groups were created according to > > > FW DRDB tables, > > > > ?? iommu_groups have nothing to do with FW tables. > Sorry, typo, ACPI drhd table. Same answer, AFAIK FW tables have no effect on iommu_groups Jason
