Hi Alex, On 1/9/18 4:07 AM, Alex Williamson wrote:
@@ -661,6 +705,8 @@ static long vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma, if (!IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu)) return 0;+ INIT_LIST_HEAD(&unmapped_regions);+ /* * We use the IOMMU to track the physical addresses, otherwise we'd * need a much more complicated tracking system. Unfortunately that @@ -698,24 +744,36 @@ static long vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma, break; }- unmapped = iommu_unmap(domain->domain, iova, len);- if (WARN_ON(!unmapped)) + entry = kzalloc(sizeof(*entry), GFP_KERNEL); + if (!entry) break;Turns out this nagged at me a bit too, this function only gets called once to dump the vfio_dma, so bailing out here leaves pages pinned and IOMMU mappings in place, for a performance optimization that we could just skip. We could sync&unpin anything collected up to this point and continue this step with a synchronous unmap/unpin. Thanks,
Ah, that's an over look in my part also. Thanks for catching this. I'll implement the fallback mechanism per your suggestion in v3. Thanks, Suravee _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
