On 17.09.2021 11:36, Roman Skakun wrote: > I use Xen PV display. In my case, PV display backend(Dom0) allocates > contiguous buffer via DMA-API to > to implement zero-copy between Dom0 and DomU. Why does the buffer need to be allocated by Dom0? If it was allocated by DomU, it could use grants to give the backend direct (zero-copy) access. Jan