Re: [PATCH v2 2/6] x86/gnttab: do not implement GNTTABOP_cache_flush

[Roger Pau Monné <roger.pau@xxxxxxxxxx>]

On Fri, May 16, 2025 at 11:48:48AM +0200, Jan Beulich wrote:
> On 16.05.2025 11:45, Roger Pau Monne wrote:
> > --- a/xen/common/Kconfig
> > +++ b/xen/common/Kconfig
> > @@ -35,6 +35,11 @@ config GRANT_TABLE
> >  
> >       If unsure, say Y.
> >  
> > +config HAS_GRANT_CACHE_FLUSH
> > +   bool
> > +   depends on GRANT_TABLE
> > +   default ARM
> 
> To keep arch stuff out of common file as much as possible, I think this 
> instead
> wants to be a "select ..." from ARM. Then:
> Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>

My first attempt was to do it as you suggest, but then if the users
disables GRANT_TABLE you get the following warning:

WARNING: unmet direct dependencies detected for HAS_GRANT_CACHE_FLUSH
  Depends on [n]: GRANT_TABLE [=n]
  Selected by [y]:
  - ARM [=y]
configuration written to .config

And you end up with the following on .config:

# CONFIG_GRANT_TABLE is not set
CONFIG_HAS_GRANT_CACHE_FLUSH=y

That's why I've done it the way presented in this patch.

Thanks, Roger.