linux-kernel - Re: [PATCH] sched/core: Fix the bug that sched_core

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: <YxB1Eu9wTPel8LWu@hirez.programming.kicks-ass.net>
Date:   Thu, 1 Sep 2022 11:02:10 +0200
From:   Peter Zijlstra <peterz@...radead.org>
To:     Cruz Zhao <CruzZhao@...ux.alibaba.com>
Cc:     mingo@...hat.com, juri.lelli@...hat.com,
        vincent.guittot@...aro.org, dietmar.eggemann@....com,
        rostedt@...dmis.org, bsegall@...gle.com, mgorman@...e.de,
        bristot@...hat.com, vschneid@...hat.com,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH] sched/core: Fix the bug that sched_core_find() may
 return throttled task

On Wed, Aug 31, 2022 at 02:49:18PM +0800, Cruz Zhao wrote:
> When a cfs_rq is throttled, the cookie'd task in this cfs_rq wouldn't
> dequeue from the core tree, and sched_core_find() may return this task,
> which will result that the throttled task running on the cpu.
> 
> To resolve this problem, we pick the first cookie matched task and
> unthrottled task.

You mean: first that that both matches the cookie and is not throttled.

Except I think you can have the same problem with the RT crud.