[PATCH 9/9] sched/rt: defer WARN console output under rq->lock

[Rik van Riel <riel@surriel.com>]

Convert the WARN*() calls that run under rq->lock or ->pi_lock to the
SCHED_WARN*() variants, so their console output is deferred to irq_work
instead of being emitted synchronously (which can deadlock via
console_unlock() -> up(&console_sem) -> try_to_wake_up() while the lock
is held).

This should prevent a deadlock if these warnings fire with a legacy
or boot console configured.

Signed-off-by: Rik van Riel <riel@surriel.com>
Assisted-by: Claude:claude-opus-4-8
---
 kernel/sched/cpupri.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/sched/cpupri.c b/kernel/sched/cpupri.c
index 8f2237e8b484..5082fb228a63 100644
--- a/kernel/sched/cpupri.c
+++ b/kernel/sched/cpupri.c
@@ -149,7 +149,7 @@ int cpupri_find_fitness(struct cpupri *cp, struct task_struct *p,
 	int task_pri = convert_prio(p->prio);
 	int idx, cpu;
 
-	WARN_ON_ONCE(task_pri >= CPUPRI_NR_PRIORITIES);
+	SCHED_WARN_ON_ONCE(task_pri >= CPUPRI_NR_PRIORITIES);
 
 	for (idx = 0; idx < task_pri; idx++) {
 
-- 
2.53.0-Meta