linux-kernel - Re: [PATCH v19 15/20] x86/resctrl: Pass two extra arguments to resctrl_arch_rmid

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <ccc29a33-d2c5-4aba-a530-240d17ae94e4@intel.com>
Date: Thu, 30 May 2024 13:24:18 -0700
From: Reinette Chatre <reinette.chatre@...el.com>
To: Tony Luck <tony.luck@...el.com>, Fenghua Yu <fenghua.yu@...el.com>, Maciej
 Wieczor-Retman <maciej.wieczor-retman@...el.com>, Peter Newman
	<peternewman@...gle.com>, James Morse <james.morse@....com>, Babu Moger
	<babu.moger@....com>, Drew Fustini <dfustini@...libre.com>, Dave Martin
	<Dave.Martin@....com>
CC: <x86@...nel.org>, <linux-kernel@...r.kernel.org>,
	<patches@...ts.linux.dev>
Subject: Re: [PATCH v19 15/20] x86/resctrl: Pass two extra arguments to
 resctrl_arch_rmid_read()

Hi Tony,

On 5/28/24 3:20 PM, Tony Luck wrote:
> For backwards compatibility on Sub-NUMA Cluster (SNC) systems the legacy
> files in the mon_L3_XX directories must report the sum of data from each
> SNC node sharing that L3 cache instance.
> 
> To make this possible, pass the "sumdomains" and "ci" fields from
> rmid_read structure as extra arguments to resctrl_arch_rmid_read().
> 
> Note that the call from check_limbo() never operates on a "sum" basis,
> so pass sumdomains=false, ci=NULL.

Why is passing "sumdomains" necessary? Can it not be inferred from
domain being NULL?

Reinette