On 20/02/19 21:15, Joao Martins wrote: > 2. PV Driver support (patches 17 - 39) > > We start by redirecting hypercalls from the backend to routines > which emulate the behaviour that PV backends expect i.e. grant > table and interdomain events. Next, we add support for late > initialization of xenbus, followed by implementing > frontend/backend communication mechanisms (i.e. grant tables and > interdomain event channels). Finally, introduce xen-shim.ko, > which will setup a limited Xen environment. This uses the added > functionality of Xen specific shared memory (grant tables) and > notifications (event channels). I am a bit worried by the last patches, they seem really brittle and prone to breakage. I don't know Xen well enough to understand if the lack of support for GNTMAP_host_map is fixable, but if not, you have to define a completely different hypercall. Of course, tests are missing. You should use the tools/testing/selftests/kvm/ framework, and ideally each patch should come with coverage for the newly-added code. Thanks, Paolo