Re: [PATCH v12 04/25] x86/resctrl: Apply Intel MBM quirk from rdt_get_l3_mon_config()

[Luck, Tony]

On Mon, Sep 21, 2026 at 12:45:02PM -0500, Babu Moger wrote:
> Hi Tony,
> 
> I cannot test the AET telemetry functionality, but I have tested the series
> on my AMD systems. It appears to work as expected, with no observed side
> effects.

Hi Babu,

Awesome. Thanks for testing.

> 
> A few comments below.
> 
> >   int __init rdt_get_l3_mon_config(struct rdt_resource *r)
> >   {
> >   	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
> > @@ -500,25 +516,14 @@ int __init rdt_get_l3_mon_config(struct rdt_resource *r)
> >   		hw_res->mbm_cntr_assign_enabled = true;
> >   	}
> > +	if (intel_rdt_mbm_need_quirk)
> > +		intel_rdt_mbm_apply_quirk(r->mon.num_rmid);
> 
> Not a bug right now.  Is it cleaner to send num_rmid instead of SNC adjusted
> r->mon.num_rmid ?

This quirk only applies to Skylake and Broadwell CPU models, which don't have
SNC. So there is no adjustment to r->mon.num_rmid. Future CPUs are using the
ACPI ERDT enumeration of MBM which includes a mechanism for RMID scaling if
needed. So this particular quirk isn't going to be re-used for new CPUs.

Is it cleaner? It's a few less characters in the source code - so maybe.

If Reinette agrees with you I can change for next spin of the series.
> 
> Thanks
> Babu

-Tony