On Mon, Jul 30, 2018 at 08:39:39AM -0600, Alex Williamson wrote: > This is more > compatible with the IOMMU mappings, Precisely. These are at page granularity. > but I don't think it can be done > atomically with respect to inflight DMA of a physical device where we > cannot halt the device without interfering with its state. Guests never add pages to the balloon if they are under DMA, so that's fine - there's never an in-flight DMA, if there is guest is buggy and it's ok to crash it. -- MST