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This causes the switching_from(), switched_from(), switching_to() and switched_to() callbacks to run even though p->sched_class remains unchanged. Set DEQUEUE_CLASS only when SCHED_FLAG_KEEP_PARAMS allows the class to change. This also ensures that incoming-class preparation added by a later change is only performed for an actual class transition. Fixes: 637b0682821b ("sched: Fold sched_class::switch{ing,ed}_{to,from}() into the change pattern") Signed-off-by: Andrea Righi --- kernel/sched/syscalls.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/sched/syscalls.c b/kernel/sched/syscalls.c index b215b0ead9a60..903b47f5d0b74 100644 --- a/kernel/sched/syscalls.c +++ b/kernel/sched/syscalls.c @@ -675,7 +675,8 @@ int __sched_setscheduler(struct task_struct *p, prev_class = p->sched_class; next_class = __setscheduler_class(policy, newprio); - if (prev_class != next_class) + if (!(attr->sched_flags & SCHED_FLAG_KEEP_PARAMS) && + prev_class != next_class) queue_flags |= DEQUEUE_CLASS; scoped_guard (sched_change, p, queue_flags) { -- 2.55.0