On Mon, Jan 28, 2019 at 06:35:34PM +0100, Cédric Le Goater wrote: > On 1/22/19 6:05 AM, Paul Mackerras wrote: > > On Mon, Jan 07, 2019 at 07:43:17PM +0100, Cédric Le Goater wrote: > >> This is the basic framework for the new KVM device supporting the XIVE > >> native exploitation mode. The user interface exposes a new capability > >> and a new KVM device to be used by QEMU. > > > > [snip] > >> @@ -1039,7 +1039,10 @@ static int kvmppc_book3s_init(void) > >> #ifdef CONFIG_KVM_XIVE > >> if (xive_enabled()) { > >> kvmppc_xive_init_module(); > >> + kvmppc_xive_native_init_module(); > >> kvm_register_device_ops(&kvm_xive_ops, KVM_DEV_TYPE_XICS); > >> + kvm_register_device_ops(&kvm_xive_native_ops, > >> + KVM_DEV_TYPE_XIVE); > > > > I think we want tighter conditions on initializing the xive_native > > stuff and creating the xive device class. We could have > > xive_enabled() returning true in a guest, and this code will get > > called both by PR KVM and HV KVM (and HV KVM no longer implies that we > > are running bare metal). > > So yes, I gave nested a try with kernel_irqchip=on and the nested hypervisor > (L1) obviously crashes trying to call OPAL. I have tighten the test with : > > if (xive_enabled() && !kvmhv_on_pseries()) { > > for now. > > As this is a problem today in 5.0.x, I will send a patch for it if you think How do you mean this is a problem today in 5.0? I just tried 5.0-rc1 with kernel_irqchip=on in a nested guest and it works just fine. What exactly did you test? > it is correct. I don't think we should bother taking care of the PR case > on P9. Should we ? We do need to take care of PR KVM on P9, since it is the only form of nested KVM that works inside a host in HPT mode. Paul.