linux-kernel - Re: [PATCH V3 02/16] perf: Fix the throttle logic for a group

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: <aChHXShBhoDBgPX7@gmail.com>
Date: Sat, 17 May 2025 10:22:53 +0200
From: Ingo Molnar <mingo@...nel.org>
To: kan.liang@...ux.intel.com
Cc: peterz@...radead.org, mingo@...hat.com, namhyung@...nel.org,
	irogers@...gle.com, mark.rutland@....com,
	linux-kernel@...r.kernel.org, linux-perf-users@...r.kernel.org,
	eranian@...gle.com, ctshao@...gle.com, tmricht@...ux.ibm.com,
	leo.yan@....com
Subject: Re: [PATCH V3 02/16] perf: Fix the throttle logic for a group


* kan.liang@...ux.intel.com <kan.liang@...ux.intel.com> wrote:

> The throttle only happens when an event is overflowed. Stop the entire
> group when any event in the group triggers the throttle.
> The MAX_INTERRUPTS is set to all throttle events.

Since this is a relatively long series with a healthy dose of 
breakage-risk, I'm wondering about bisectability:

 - patch #2 auto-throttles groups, ie. stops the PMU

 - patches #3-#16 removes explicit PMU-stop calls.

In the interim commits, will the double PMU-stop in drivers not updated 
yet do anything noticeable, such as generate warnings, etc?

Thanks,

	Ingo