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From: Tejun Heo <tj@kernel.org>
To: KobaK <kobak@nvidia.com>
Cc: David Vernet <void@manifault.com>,
	Andrea Righi <arighi@nvidia.com>,
	Changwoo Min <changwoo@igalia.com>,
	Ingo Molnar <mingo@redhat.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Juri Lelli <juri.lelli@redhat.com>,
	Vincent Guittot <vincent.guittot@linaro.org>,
	Dietmar Eggemann <dietmar.eggemann@arm.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Ben Segall <bsegall@google.com>, Mel Gorman <mgorman@suse.de>,
	Valentin Schneider <vschneid@redhat.com>,
	sched-ext@lists.linux.dev, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] sched/ext: fix cpumask leak in scx_init() error path
Date: Wed, 8 Apr 2026 15:14:58 -1000	[thread overview]
Message-ID: <adb9knvhHdYaqhAP@slm.duckdns.org> (raw)
In-Reply-To: <20260408172312.2178104-1-kobak@nvidia.com>

On Thu, Apr 09, 2026 at 01:23:12AM +0800, KobaK wrote:
> From: Koba Ko <kobak@nvidia.com>
> 
> In scx_init(), two cpumask allocations are combined with || short-circuit
> evaluation. If the first alloc_cpumask_var (scx_bypass_lb_donee_cpumask)
> succeeds but the second (scx_bypass_lb_resched_cpumask) fails, the first
> cpumask is leaked.

This is an initcall. It runs once and failure is a kernel bug triggering a
WARN. It won't fail and error handling is meaningless here. Once you fail
one of these, the system is not in a good state as later code paths assume
that these succeeded during boot. Not freeing is the least of our problems.

Thanks.

-- 
tejun

      parent reply	other threads:[~2026-04-09  1:14 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-04-08 17:23 [PATCH] sched/ext: fix cpumask leak in scx_init() error path KobaK
2026-04-08 17:34 ` Andrea Righi
2026-04-08 18:54   ` Cheng-Yang Chou
2026-04-09  1:14 ` Tejun Heo [this message]

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