Tell me it isn't so... diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c index 59f17ac..6c588ee 100644 --- a/drivers/pci/intel-iommu.c +++ b/drivers/pci/intel-iommu.c @@ -3866,6 +3866,20 @@ static int intel_iommu_unmap(struct iommu_domain *domain, struct dmar_domain *dmar_domain = domain->priv; size_t size = PAGE_SIZE << gfp_order; + /* The KVM code is *fucked* in the head. It maps the range + one page at a time, using 4KiB pages unless it actually + allocated hugepages using hugetlbfs. (So we get to flush + the CPU data cache and then the IOTLB for each page in + its loop). And on unmap, it unmaps 4KiB at a time (always + passing gfp_order==0), regardless of whether it mapped + using superpages or not. So on unmap, if we detect a + superpage in our page tables we are expected to unmap + *more* than we are asked to, and return a value indicating + how much we actually unmapped. WTF? */ + if (dma_pfn_level_pte (dmar_domain, iova >> VTD_PAGE_SHIFT, + 1, &gfp_order)) + size = PAGE_SIZE << gfp_order; + dma_pte_clear_range(dmar_domain, iova >> VTD_PAGE_SHIFT, (iova + size - 1) >> VTD_PAGE_SHIFT); -- David Woodhouse Open Source Technology Centre David.Woodhouse@xxxxxxxxx Intel Corporation -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
