linux-kernel - [PATCH v3 0/2] Fix SCHED_IDLE behavior on wakeup preemption

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-next>] [day] [month] [year] [list]

Message-Id: <20250307032118.30364-1-wuyun.abel@bytedance.com>
Date: Fri,  7 Mar 2025 11:21:14 +0800
From: Abel Wu <wuyun.abel@...edance.com>
To: K Prateek Nayak <kprateek.nayak@....com>,
	Madadi Vineeth Reddy <vineethr@...ux.ibm.com>,
	Phil Auld <pauld@...hat.com>,
	Ingo Molnar <mingo@...hat.com>,
	Peter Zijlstra <peterz@...radead.org>,
	Juri Lelli <juri.lelli@...hat.com>,
	Vincent Guittot <vincent.guittot@...aro.org>,
	Dietmar Eggemann <dietmar.eggemann@....com>,
	Steven Rostedt <rostedt@...dmis.org>,
	Ben Segall <bsegall@...gle.com>,
	Mel Gorman <mgorman@...e.de>,
	Valentin Schneider <vschneid@...hat.com>,
	Josh Don <joshdon@...gle.com>,
	Tianchen Ding <dtcccc@...ux.alibaba.com>
Cc: Abel Wu <wuyun.abel@...edance.com>,
	linux-kernel@...r.kernel.org (open list:SCHEDULER)
Subject: [PATCH v3 0/2] Fix SCHED_IDLE behavior on wakeup preemption

The commit 6bc912b71b6f ("sched: SCHED_OTHER vs SCHED_IDLE isolation")
defines the behavior of SCHED_IDLE as following:

 - no SCHED_IDLE buddies
 - never let SCHED_IDLE preempt on wakeup
 - always preempt SCHED_IDLE on wakeup
 - limit SLEEPER fairness for SCHED_IDLE

and the middle two of them are broken now.

v3:
 - Collect Tested-by and Acked-by from K Nayak and Vincent, thanks!

v2:
 - Collect Reviewed-by tags from Vincent, Josh and Madadi, thanks!
 - Rebased to up-to-date tip. (Madadi)
 - Folded some discussion with Vincent into commit log.

Abel Wu (2):
  sched/fair: Do not let idle entities preempt others
  sched/fair: Fix premature check of WAKEUP_PREEMPTION

 kernel/sched/fair.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

-- 
2.37.3