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

[Reinette Chatre]

Hi Tony,

To not document code the subject could be something like:
	x86/resctrl: Apply MBM quirk during feature enumeration

On 9/16/26 4:12 PM, Tony Luck wrote:
> The Intel quirk to adjust Memory Bandwidth Monitoring (MBM) values on
> certain CPUs is applied early, before discovering if MBM is supported.
> 
> Move the call into rdt_get_l3_mon_config(), but keep the decision on
> whether it is needed in __check_quirks_intel() with all the other
> model specific tests.

Last paragraph just documents the code change without any explanation
*why* this change is needed. Consider something like below (just a draft,
and suggestion, please improve from here).

	The Intel MBM correction factor quirk is applied during early CPU model
	checks using the RMID count from cpuinfo_x86::x86_cache_max_rmid. It is
	the last consumer of the resctrl fields in struct cpuinfo_x86 now that
	monitoring feature enumeration is contained within resctrl.

	This lone consumer prevents those fields from being removed, and applies
	MBM specific setup before resctrl has established that MBM is supported.

	Apply the quirk during monitoring feature enumeration in preparation
	for removing the resctrl fields from struct cpuinfo_x86.
	Keep the decision on whether the quirk is needed with the other model
	specific tests to avoid scattering quirk handling.

	No functional change intended.
	
Reinette