linux-kernel - Re: [PATCH 6.12 000/122] 6.12.11-rc1 review

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: <20250128143949.GD7145@noisy.programming.kicks-ass.net>
Date: Tue, 28 Jan 2025 15:39:49 +0100
From: Peter Zijlstra <peterz@...radead.org>
To: Mike Galbraith <efault@....de>
Cc: Ron Economos <re@...z.net>, Arnd Bergmann <arnd@...db.de>,
	Naresh Kamboju <naresh.kamboju@...aro.org>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	stable@...r.kernel.org, patches@...ts.linux.dev,
	linux-kernel@...r.kernel.org,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Guenter Roeck <linux@...ck-us.net>, shuah <shuah@...nel.org>,
	patches@...nelci.org, lkft-triage@...ts.linaro.org,
	Pavel Machek <pavel@...x.de>, Jon Hunter <jonathanh@...dia.com>,
	Florian Fainelli <f.fainelli@...il.com>,
	Sudip Mukherjee <sudipm.mukherjee@...il.com>, srw@...dewatkins.net,
	rwarsow@....de, Conor Dooley <conor@...nel.org>,
	hargar@...rosoft.com, Mark Brown <broonie@...nel.org>,
	Anders Roxell <anders.roxell@...aro.org>,
	Vincent Guittot <vincent.guittot@...aro.org>,
	Dan Carpenter <dan.carpenter@...aro.org>
Subject: Re: [PATCH 6.12 000/122] 6.12.11-rc1 review

On Tue, Jan 28, 2025 at 12:46:07PM +0100, Mike Galbraith wrote:

> Seems 6.13 is gripe free thanks to it containing 4423af84b297.
> 
> I stumbled upon a reproducer for my x86_64 desktop box: all I need do
> is fire up a kvm guest in an enterprise configured host.  That inspires
> libvirt goop to engage group scheduling, splat follows instantly.
> 
> Back 4423af84b297 out of 6.13, it starts griping, add it to a 6.12 tree
> containing 6d71a9c61604, it stops doing so.

Ooh, does something like the below (+- reverse-renames as applicable to
.12) also help?

---
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index b67222dea491..8766f7d3d297 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -3781,6 +3781,7 @@ static void reweight_entity(struct cfs_rq *cfs_rq, struct sched_entity *se,
 		update_entity_lag(cfs_rq, se);
 		se->deadline -= se->vruntime;
 		se->rel_deadline = 1;
+		cfs_rq->nr_queued--;
 		if (!curr)
 			__dequeue_entity(cfs_rq, se);
 		update_load_sub(&cfs_rq->load, se->load.weight);
@@ -3811,6 +3812,7 @@ static void reweight_entity(struct cfs_rq *cfs_rq, struct sched_entity *se,
 		place_entity(cfs_rq, se, 0);
 		if (!curr)
 			__enqueue_entity(cfs_rq, se);
+		cfs_rq->nr_queued++;
 
 		/*
 		 * The entity's vruntime has been adjusted, so let's check