Re: [PATCH v2 06/10] x86/virt/tdx: Refine a comment to reflect the latest TDX spec

[Huang, Kai]

On Mon, 2024-08-05 at 20:43 -0700, Williams, Dan J wrote:
> Kai Huang wrote:
> > The old versions of "Intel TDX Module v1.5 ABI Specification" contain
> > the definitions of all global metadata field IDs directly in a table.
> > 
> > However, the latest spec moves those definitions to a dedicated
> > 'global_metadata.json' file as part of a new (separate) "Intel TDX
> > Module v1.5 ABI definitions" [1].
> > 
> > Update the comment to reflect this.
> > 
> > [1]: https://cdrdv2.intel.com/v1/dl/getContent/795381
> > 
> > Signed-off-by: Kai Huang <kai.huang@xxxxxxxxx>
> > ---
> > 
> > v1 -> v2:
> >  - New patch to fix a comment spotted by Nikolay.
> > 
> > ---
> >  arch/x86/virt/vmx/tdx/tdx.h | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/arch/x86/virt/vmx/tdx/tdx.h b/arch/x86/virt/vmx/tdx/tdx.h
> > index fdb879ef6c45..4e43cec19917 100644
> > --- a/arch/x86/virt/vmx/tdx/tdx.h
> > +++ b/arch/x86/virt/vmx/tdx/tdx.h
> > @@ -29,7 +29,7 @@
> >  /*
> >   * Global scope metadata field ID.
> >   *
> > - * See Table "Global Scope Metadata", TDX module 1.5 ABI spec.
> > + * See the "global_metadata.json" in the "TDX 1.5 ABI definitions".
> >   */
> >  #define MD_FIELD_ID_MAX_TDMRS			0x9100000100000008ULL
> >  #define MD_FIELD_ID_MAX_RESERVED_PER_TDMR	0x9100000100000009ULL
> 
> Given this is JSON any plan to just check-in "global_metadata.json"
> somewhere in tools/ with a script that queries for a set of fields and
> spits them out into a Linux data structure + set of TD_SYSINFO_*_MAP()
> calls? Then no future review bandwidth needs to be spent on manually
> checking offsets names and values, they will just be pulled from the
> script.

This seems a good idea.  I'll add this to my TODO list and evaluate it
first.

One minor issue is some metadata fields may need special handling.  E.g.,
MAX_VCPUS_PER_TD (which is u16) may not be supported by some old TDX
modules, but this isn't an error because we can just treats it as
U16_MAX.