From 6ee471b646e09203f8dca27ffff78bb454dc97ac Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 23 Jul 2026 15:07:56 -1000 Subject: sched_ext: Use rcu_access_pointer() for the first_task comparison dsq->first_task is __rcu for the lockless scx_bpf_dsq_peek(). The task removal path compares it against the departing task with a plain load, which sparse flags. The comparison runs under the dsq lock and only tests identity, so rcu_access_pointer() is the fit. Signed-off-by: Tejun Heo --- kernel/sched/ext/ext.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/ext/ext.c b/kernel/sched/ext/ext.c index 2002ab0f7c9b..79dc258515e7 100644 --- a/kernel/sched/ext/ext.c +++ b/kernel/sched/ext/ext.c @@ -1654,7 +1654,7 @@ static void task_unlink_from_dsq(struct task_struct *p, list_del_init(&p->scx.dsq_list.node); dsq_dec_nr(dsq, p); - if (!(dsq->id & SCX_DSQ_FLAG_BUILTIN) && dsq->first_task == p) { + if (!(dsq->id & SCX_DSQ_FLAG_BUILTIN) && rcu_access_pointer(dsq->first_task) == p) { struct task_struct *first_task; first_task = nldsq_next_task(dsq, NULL, false); -- cgit v1.2.3