Re: [PATCH v6 17/22] x86/virt/tdx: Avoid updates during update-sensitive operations

[Kiryl Shutsemau]

On Tue, Mar 31, 2026 at 10:34:04AM +0800, Chao Gao wrote:
> On Mon, Mar 30, 2026 at 01:07:27PM +0000, Kiryl Shutsemau wrote:
> >On Thu, Mar 26, 2026 at 01:44:08AM -0700, Chao Gao wrote:
> >> +	if (tdx_sysinfo.features.tdx_features0 & TDX_FEATURES0_UPDATE_COMPAT)
> >> +		args.rcx |= TDX_SYS_SHUTDOWN_AVOID_COMPAT_SENSITIVE;
> >
> >I think you need to explain what would happen if the feature is not
> >supported.
> 
> I included this explanation in the changelog:
> 
>   When the "avoid update-sensitive" feature isn't supported by the TDX
>   module, proceed with updates and let userspace update at their own risk.
>   ...
>   
> Do you mean making it more explicit:
> 
>   When the "avoid update-sensitive" feature isn't supported, proceed with
>   updates. If a race occurs between module update and update-sensitive
>   operations, failures happen at a later stage (e.g., incorrect TD
>   measurements in attestation reports for TD build). Effectively, this
>   means "let userspace update at their own risk." ...

I missed that, sorry. But the more explicit version is better.

-- 
  Kiryl Shutsemau / Kirill A. Shutemov