On 05/07/2017 08:23, Fam Zheng wrote: >> req->vq = vq; >> req->dev = s; >> - qemu_sglist_init(&req->qsgl, DEVICE(s), 8, &address_space_memory); >> + qemu_sglist_init(&req->qsgl, DEVICE(s), 8, vdev->dma_as); > Not related to this patch, but is our vIOMMU iotlb implementation safe for > data > plane (both virtio-blk and virtio-scsi)? There we don't have BQL to > synchronize > between IOVA lookup and update, which means threads can race when accessing > the > iotlb GHashTable. > > Did I overlook a synchronization mechanism? Or is it missing? Paolo, MST?
I think it's missing. One way to fix it could be to finish the MemoryRegionCache work and have an IOMMU->virtio notifier, similar to how vhost works. Paolo
