Re: [PATCH v19 105/130] KVM: TDX: handle KVM hypercall with TDG.VP.VMCALL

From: Isaku Yamahata
Date: Wed Apr 17 2024 - 03:03:07 EST


On Wed, Apr 17, 2024 at 02:16:57PM +0800,
Binbin Wu <binbin.wu@xxxxxxxxxxxxxxx> wrote:

>
>
> On 4/4/2024 9:27 AM, Isaku Yamahata wrote:
> > On Tue, Apr 02, 2024 at 04:52:46PM +0800,
> > Chao Gao <chao.gao@xxxxxxxxx> wrote:
> >
> > > > +static int tdx_emulate_vmcall(struct kvm_vcpu *vcpu)
> > > > +{
> > > > + unsigned long nr, a0, a1, a2, a3, ret;
> > > > +
> > > do you need to emulate xen/hyper-v hypercalls here?
> >
> > No. kvm_emulate_hypercall() handles xen/hyper-v hypercalls,
> > __kvm_emulate_hypercall() doesn't.
> So for TDX, kvm doesn't support xen/hyper-v, right?
>
> Then, should KVM_CAP_XEN_HVM and KVM_CAP_HYPERV be filtered out for TDX?

That's right. We should update kvm_vm_ioctl_check_extension() and
kvm_vcpu_ioctl_enable_cap(). I didn't pay attention to them.
--
Isaku Yamahata <isaku.yamahata@xxxxxxxxx>