On Tue, Apr 18, 2017 at 04:30:40AM +0000, Liu, Yi L wrote: [...]
> > +static void vtd_switch_address_space(VTDAddressSpace *as) { > > + bool use_iommu; > > + > > + assert(as); > > + > > + use_iommu = as->iommu_state->dmar_enabled; > > + if (use_iommu) { > > + /* Further checks per-device configuration */ > > + use_iommu &= !vtd_dev_pt_enabled(as); > > + } > > + > > + trace_vtd_switch_address_space(pci_bus_num(as->bus), > > + VTD_PCI_SLOT(as->devfn), > > + VTD_PCI_FUNC(as->devfn), > > + use_iommu); > > Hi Peter, > > Skip address space switching is a good idea to support Passthru mode. > However, without the address space, the vfio notifier would not be > registered, thus vIOMMU emulator has no way to connect to host. It is > no harm if there is only map/unmap notifier. But if we have more notifiers > other than map/unmap, it may be a problem. > > I think we need to reconsider it here. For now I think as switching is good to us in general. Could I know more context about this? Would it be okay to work on top of this in the future? Thanks, -- Peter Xu