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I'll update this in v4. >> Introduce amd_iommu_trans_devid_reserve_pci_aliases() in trans_devid.c and >> invoke it from amd_iommu_attach_device() immediately after the primary >> amd_iommu_trans_devid_reserve() succeeds. For PCI devices the helper >> reserves the IVRS alias when it differs from the device BDF, then walks >> pci_for_each_dma_alias() and reserves each alias BDF. Repeated attach and >> overlap with the primary BDF in the PCI walk are handled by the existing >> idempotency of amd_iommu_trans_devid_reserve() (a second reserve of an >> already-reserved id succeeds). > > It would be so nice if the AMD driver could get fixed up to work more > like ARM with the alais devids. > > ie on probe you allocate an array of all the alias dev ids, fill it in > with the information from PCI and then never touch the PCI again. > > Then you'd just dump the whole array into the allocator in one clean > shot and this would all be simpler. > > Instead we have these endless pci walks every where :\ > > But its fine like this I suppose I agree. Let me look into this in following this series, and propose change. Thanks, Suravee