On 20/05/19 13:30, Thomas Huth wrote: >> No objections at all, though it would be like to have ucall plumbed in >> from the beginning. > I'm still looking at the ucall interface ... what I don't quite get yet > is the question why the ucall_type there is selectable during runtime? > > Are there plans to have test that could either use UCALL_PIO or > UCALL_MMIO? If not, what about moving ucall_init() and ucall() to > architecture specific code in tools/testing/selftests/kvm/lib/aarch64/ > and tools/testing/selftests/kvm/lib/x86_64 instead, and to remove the > ucall_type stuff again (so that x86 is hard-wired to PIO and aarch64 > is hard-wired to MMIO)? ... then I could add a DIAG-based ucall > on s390x more easily, I think. Yes, that would work. I think Andrew wanted the flexibility to use MMIO on x86, but it's not really necessary to have it. Paolo