On Mon, Aug 06, 2018 at 11:35:39PM +0300, Michael S. Tsirkin wrote:

quoted

As I said replying to Christoph, we are "leaking" into the interface
something here that is really what's the VM is doing to itself, which
is to stash its memory away in an inaccessible place.

Cheers,
Ben.

I think Christoph merely objects to the specific implementation.  If
instead you do something like tweak dev->bus_dma_mask for the virtio
device I think he won't object.

As long as we also document how dev->bus_dma_mask is tweaked for this
particular virtual bus, yes.