linux-kernel - RE: [PATCH v8 00/32] x86,fs/resctrl telemetry monitoring

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 for Android: free password hash cracker in your pocket

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

Message-ID: <SJ1PR11MB6083B735CCDA74D30F605FD5FC3BA@SJ1PR11MB6083.namprd11.prod.outlook.com>
Date: Thu, 28 Aug 2025 23:49:14 +0000
From: "Luck, Tony" <tony.luck@...el.com>
To: "Chatre, Reinette" <reinette.chatre@...el.com>
CC: Fenghua Yu <fenghuay@...dia.com>, "Wieczor-Retman, Maciej"
	<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>, "Chen,
 Yu C" <yu.c.chen@...el.com>, "x86@...nel.org" <x86@...nel.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"patches@...ts.linux.dev" <patches@...ts.linux.dev>
Subject: RE: [PATCH v8 00/32] x86,fs/resctrl telemetry monitoring

>> If that isn't sufficient, can you expand on your thoughts about a helper
>> in the INTEL_PMT_TELEMETRY subsystem?
>
> Updating the changelog to highlight that INTEL_PMT_TELEMETRY provides a copy of
> a struct pmt_feature_group for resctrl's private use instead of a reference to an
> existing one will be sufficient..

Okay. I will update the comment.

I checked with David about whether the resources might be unmapped underneath us
since there is no additional reference taken when INTEL_PMT_TELEMETRY hands
us this copy. The answer is currently "no". The mappings would only be released if
the INTEL_PMT_TELEMTRY driver were unloaded. But we require the driver to be
built-in so that we can call from resctrl.

This could change if resctrl ever becomes a loadable module and we remove the
requirement that INTEL_PMT_TELEMTRY be built in.

-Tony