Fix a RT tasks related lockup/live-lock during CPU offlining.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'sched-urgent-2023-10-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler fix from Ingo Molnar:
 "Fix a RT tasks related lockup/live-lock during CPU offlining"

* tag 'sched-urgent-2023-10-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/rt: Fix live lock between select_fallback_rq() and RT push
This commit is contained in:
Linus Torvalds 2023-10-01 09:38:05 -07:00
commit c5ecffe6d3

View file

@ -101,6 +101,7 @@ static inline int __cpupri_find(struct cpupri *cp, struct task_struct *p,
if (lowest_mask) {
cpumask_and(lowest_mask, &p->cpus_mask, vec->mask);
cpumask_and(lowest_mask, lowest_mask, cpu_active_mask);
/*
* We have to ensure that we have at least one bit