Re: [PATCH v7 07/10] x86/vmscape: Use static_call() for predictor flush

[Pawan Gupta]

On Thu, Mar 19, 2026 at 04:56:52PM +0000, bot+bpf-ci@xxxxxxxxxx wrote:
> > diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
> > index 68e2df3e3bf58..b75eda114503a 100644
> > --- a/arch/x86/kernel/cpu/bugs.c
> > +++ b/arch/x86/kernel/cpu/bugs.c
> > @@ -144,6 +144,17 @@ EXPORT_SYMBOL_GPL(cpu_buf_idle_clear);
> >   */
> >  DEFINE_STATIC_KEY_FALSE(switch_mm_cond_l1d_flush);
> >
> > +/*
> > + * Controls CPU Fill buffer clear before VMenter. This is a subset of
> > + * X86_FEATURE_CLEAR_CPU_BUF, and should only be enabled when KVM-only
> > + * mitigation is required.
> > + */
> > +DEFINE_STATIC_KEY_FALSE(cpu_buf_vm_clear);
> > +EXPORT_SYMBOL_GPL(cpu_buf_vm_clear);
> 
> cpu_buf_vm_clear is defined and exported here but appears to have no
> users. There is no declaration in any header, and nothing in this
> patch series references it.
> 
> The comment describes CPU fill buffer clearing before VMenter, which
> seems unrelated to the predictor flush static_call conversion that
> this patch is doing. Was this included by mistake, or is it intended
> for a follow-up series?

Agh, that is introduced by a wrong conflict resolution during rebase,
removed now.

> > +
> > +DEFINE_STATIC_CALL_NULL(vmscape_predictor_flush, write_ibpb);
> > +EXPORT_STATIC_CALL_GPL(vmscape_predictor_flush);