Hi Jean-Philippe, On 19/01/18 17:21, Jean-Philippe Brucker wrote: > On 16/01/18 23:26, Auger Eric wrote: > [...] >>> + switch (mem->subtype) { >>> + case VIRTIO_IOMMU_RESV_MEM_T_MSI: >>> + region = iommu_alloc_resv_region(addr, size, prot, >>> + IOMMU_RESV_MSI); >> if (!region) >> return -ENOMEM; >>> + break; >>> + case VIRTIO_IOMMU_RESV_MEM_T_RESERVED: >>> + default: >>> + region = iommu_alloc_resv_region(addr, size, 0, >>> + IOMMU_RESV_RESERVED); >> same. > > I'll add them, thanks > >> There is another issue related to the exclusion of iovas belonging to >> reserved regions. Typically on x86, when attempting to run >> virtio-blk-pci with iommu I eventually saw the driver using iova >> belonging to the IOAPIC regions to map phys addr and this stalled qemu >> with a drown trace: >> >> "virtio: bogus descriptor or out of resources" >> >> those regions need to be excluded from the iova allocator. This was >> resolved by adding >> if (iommu_dma_init_domain(domain, >> vdev->viommu->geometry.aperture_start, >> vdev->viommu->geometry.aperture_end, >> dev)) >> in viommu_attach_dev() > > The most recent hack for x86 [1] does call iommu_dma_init_domain() in > attach_dev(). Is it buggy? Oh OK. Actually I have never used that branch and in my version the last arg of iommu_dma_init_domain was NULL hence the issue. But I was thinking more generally that care must be taken to exclude all those regions. Thanks Eric > > We probably shouldn't call iommu_dma_init_domain() unconditionally > (outside of CONFIG_X86 that is), since it's normally done by the arch > (arch/arm64/mm/dma-mapping.c) > > Thanks, > Jean > > [1] > http://www.linux-arm.org/git?p=linux-jpb.git;a=commitdiff;h=e910e224b58712151dda06df595a53ff07edef63 > on branch virtio-iommu/v0.5-x86 > _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization