On Mon, 29 Jun 2020 at 23:42, Sean Christopherson <sean.j.christopherson@xxxxxxxxx> wrote: > > On Mon, Jun 29, 2020 at 03:59:25PM +0200, Paolo Bonzini wrote: > > On 29/06/20 15:46, Vitaly Kuznetsov wrote: > > >> + if (!lapic_in_kernel(vcpu)) > > >> + return 1; > > >> + > > > I'm not sure how much we care about !lapic_in_kernel() case but this > > > change should be accompanied with userspace changes to not expose > > > KVM_FEATURE_ASYNC_PF_INT or how would the guest know that writing a > > > legitimate value will result in #GP? > > > > Almost any pv feature is broken with QEMU if kernel_irqchip=off. I > > wouldn't bother and I am seriously thinking of dropping all support for > > that, including: > > Heh, based on my limited testing, that could be "Almost everything is > broken with Qemu if kernel_irqchip=off". It is broken for several years. :)