Re: [PATCH 2/6] x86/virt/tdx: Configure add-on features on TDX module init and update

On Fri, Aug 21, 2026 at 07:38:42AM -0700, Dave Hansen wrote:
> On 8/20/26 20:29, Xu Yilun wrote:
> >  static __init int tdx_sys_config(struct tdmr_info_pa_array *tdmr_pa_array,
> > -				 u64 nr_tdmr_pa, u64 global_keyid)
> > +				 u64 nr_tdmr_pa, u64 global_keyid,
> > +				 u64 addon_features0)
> 
> addon_features0 is just a copy of the global, static, not changing
> get_tdx_addon_features0() return code, right?
> 
> Why pass it around as a function argument?

I thought that we need some place to explicitly see the TDX ABI
definition - what are the inputs the host should provide to the module.

The addon_features0 is the *option* the host should provide to the
module according to the ABI. The global, static value for addon_features0
is Linux's policy. So if we need to explicit the policy by the code,
this helper and its arguments are good places to show the boundary.

But yes it does add boilerplate to the code, I can drop it.