From: Tejun Heo <tj@kernel.org>
To: David Vernet <void@manifault.com>,
Andrea Righi <arighi@nvidia.com>,
Changwoo Min <changwoo@igalia.com>
Cc: Zhao Mengmeng <zhaomengmeng@kylinos.cn>,
Emil Tsalapatis <emil@etsalapatis.com>,
sched-ext@lists.linux.dev, linux-kernel@vger.kernel.org,
Tejun Heo <tj@kernel.org>
Subject: [PATCH sched_ext/for-7.1] sched_ext: Drop spurious warning on kick during scheduler disable
Date: Fri, 10 Apr 2026 10:20:54 -1000 [thread overview]
Message-ID: <20260410202054.4189994-1-tj@kernel.org> (raw)
kick_cpus_irq_workfn() warns when scx_kick_syncs is NULL, but this can
legitimately happen when a BPF timer or other kick source races with
free_kick_syncs() during scheduler disable. Drop the pr_warn_once() and
add a comment explaining the race.
Signed-off-by: Tejun Heo <tj@kernel.org>
---
kernel/sched/ext.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c
index b8dbae251fd5..012ca8bd70fb 100644
--- a/kernel/sched/ext.c
+++ b/kernel/sched/ext.c
@@ -7600,10 +7600,9 @@ static void kick_cpus_irq_workfn(struct irq_work *irq_work)
unsigned long *ksyncs;
s32 cpu;
- if (unlikely(!ksyncs_pcpu)) {
- pr_warn_once("kick_cpus_irq_workfn() called with NULL scx_kick_syncs");
+ /* can race with free_kick_syncs() during scheduler disable */
+ if (unlikely(!ksyncs_pcpu))
return;
- }
ksyncs = rcu_dereference_bh(ksyncs_pcpu)->syncs;
--
2.53.0
next reply other threads:[~2026-04-10 20:20 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-04-10 20:20 Tejun Heo [this message]
2026-04-10 23:17 ` [PATCH sched_ext/for-7.1] sched_ext: Drop spurious warning on kick during scheduler disable Zhao mengmeng
2026-04-11 2:41 ` Tejun Heo
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