On Wed, Jun 22, 2022 at 12:11:25PM -0500, Suravee Suthikulpanit wrote: > #ifdef CONFIG_IRQ_REMAP > +/* > + * Iterate through all the IOMMUs to verify if the specified > + * EFR bitmask of IOMMU feature are set. > + * Warn and return false if found inconsistency. > + */ > static bool check_feature_on_all_iommus(u64 mask) > { > bool ret = false; > struct amd_iommu *iommu; > > for_each_iommu(iommu) { > - ret = iommu_feature(iommu, mask); > - if (!ret) > + bool tmp = iommu_feature(iommu, mask); > + > + if ((ret != tmp) && > + !list_is_first(&iommu->list, &amd_iommu_list)) { > + pr_err(FW_BUG "Found inconsistent EFR mask (%#llx) on > iommu%d (%04x:%02x:%02x.%01x).\n", > + mask, iommu->index, iommu->pci_seg->id, > PCI_BUS_NUM(iommu->devid), > + PCI_SLOT(iommu->devid), PCI_FUNC(iommu->devid)); > return false; > + } > + ret = tmp;
It is better to implement this by introducing a global feature mask, which represents the minial set of features supported by any IOMMU in the system. The warning is then something like: if ((global_feature_mask & iommu_features) != global_feature_mask) pr_warn(...); This also makes the global variable to track SNP support obsolete. Regards, Joerg _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu