Hi Eric,
I love your patch! Yet something to improve:
[auto build test ERROR on iommu/next]
[also build test ERROR on linus/master v5.6-rc6 next-20200320]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option
Up to now, when the type was UNMANAGED, we used to
allocate IOVA pages within a reserved IOVA MSI range.
If both the host and the guest are exposed with SMMUs, each
would allocate an IOVA. The guest allocates an IOVA (gIOVA)
to map onto the guest MSI doorbell (gDB). The Host allocates
another IOVA
