[PATCH v3 3/8] x86, lib: Add WBNOINVD helper functions

[Peter Zijlstra]

On Thu, Jul 10, 2025 at 01:29:02PM +0200, Borislav Petkov wrote:
> On Thu, May 22, 2025 at 04:37:27PM -0700, Sean Christopherson wrote:
> > diff --git a/arch/x86/lib/cache-smp.c b/arch/x86/lib/cache-smp.c
> > index 079c3f3cd32c..1789db5d8825 100644
> > --- a/arch/x86/lib/cache-smp.c
> > +++ b/arch/x86/lib/cache-smp.c
> > @@ -19,3 +19,14 @@ void wbinvd_on_all_cpus(void)
> >  	on_each_cpu(__wbinvd, NULL, 1);
> >  }
> >  EXPORT_SYMBOL(wbinvd_on_all_cpus);
> > +
> > +static void __wbnoinvd(void *dummy)
> > +{
> > +	wbnoinvd();
> > +}
> > +
> > +void wbnoinvd_on_all_cpus(void)
> > +{
> > +	on_each_cpu(__wbnoinvd, NULL, 1);
> > +}
> > +EXPORT_SYMBOL(wbnoinvd_on_all_cpus);
> 
> If there's no particular reason for the non-GPL export besides being
> consistent with the rest - yes, I did the change for wbinvd_on_all_cpus() but
> that was loooong time ago - I'd simply make this export _GPL.

Uhhhh, how about we use this fancy export to known modules only thing
for this?

These are typical things we do *NOT* want people to actually use.