On Mon, 2023-02-27 at 13:26 -0800, Isaku Yamahata wrote: > > > TDX attestation includes the maximum number of vcpu that the guest can > > > accommodate. > > > > > > > I don't understand why "attestation" is the reason here. Let's say TDX is > > used > > w/o attestation, I don't think this patch can be discarded? > > > > IMHO the true reason is TDX has it's own control of maximum number of vcpus, > > i.e. asking you to specify the value when creating the TD. Therefore, the > > constant KVM_MAX_VCPUS doesn't work for TDX guest anymore. > > Without TDX attestation, this can be discarded. The TD is created with > max_vcpus=KVM_MAX_VCPUS by default. This parses like: If we have attestation, the TD can be created with a user-specified non-default value. Otherwise, the TD is always created with default value. It doesn't make sense, right? Because architecturally whether TD can be created with a user specified value doesn't depend on attestation at all.
