Re: [PATCH v19 039/130] KVM: TDX: initialize VM with TDX specific parameters

Edgecombe, Rick P
2024-04-11T19:52:08Z

On Thu, 2024-04-11 at 12:26 -0700, Isaku Yamahata wrote:
> >
> > So this enables features based on xss support in the passed CPUID, but these
> > features are not
> > dependent xsave. You could have CET without xsave support. And in fact
> > Kernel IBT doesn't use it. To
> > utilize CPUID leafs to configure features, but diverge from the HW meaning
> > seems like asking for
> > trouble.
>
> TDX module checks the consistency.  KVM can rely on it not to re-implement it.
> The TDX Base Architecture specification describes what check is done.
> Table 11.4: Extended Features Enumeration and Execution Control

The point is that it is an strange interface. Why not take XFAM as a specific
field in struct kvm_tdx_init_vm?