Re: [PATCH v3 0/4] KVM: TDX: Validate directly configurable CPUID bits

[Edgecombe, Rick P]

On Wed, 2026-09-02 at 18:29 +0800, Xiaoyao Li wrote:
> So the proposal is making TDX behave as if the relevant VMCS save/load 
> controls (if any) are set around TDH.VP.ENTER.
> 
> In fact, what matters for host vmm is just the VM_EXIT_LOAD_XXX control. 
> So the proposal becomes "If there is VM_EXIT_LOAD_XXX control for a 
> state, TDX needs to restore the host state after TDH.VP.ENTER. If no 
> such contorl, TDX sets the state to INIT state after TDH.VP.ENTER".
> 
> It's a fancy idea. And it provides a clear rule of how TDX handles 
> states of a feature so that host VMM developers don't need to read the 
> TDX module API to figure out what's the value of a state after TDH.VP.ENTER.
> 
> It's helpful for host VMM developers, though I'm not sure on TDX module 
> developers.

I don't think they have agreed to it yet (Binbin?), but I think it mostly works
this way already. Why do you think it is a burden on TDX module developers?

Also, I think this can be the guideline. We could have exceptions.