Messages in this thread | | | Date | Fri, 26 Aug 2022 20:45:54 +0200 | Subject | Re: [PATCH v7 1/2] sched/rt: fix bad task migration for rt tasks | From | Dietmar Eggemann <> |
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On 13/07/2022 15:48, Schspa Shi wrote: > Commit 95158a89dd50 ("sched,rt: Use the full cpumask for balancing") > allow find_lock_lowest_rq to pick a task with migration disabled. > This commit is intended to push the current running task on this CPU > away. > > There is a race scenario, which allows a migration disabled task to > be migrated to another CPU. > > When there is a RT task with higher priority, rt sched class was > intended to migrate higher priority task to lowest rq via push_rt_tasks, > this BUG will happen here. ^^^
You mean the warning in set_task_cpu()?
> With the system running on PREEMPT_RT, rt_spin_lock will disable > migration, this will make the problem easier to reproduce. > > I have seen this crash on PREEMPT_RT, from the logs, there is a race ^^^^^ ?
We still talking about the set_task_cpu() warning, right?
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Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
You should carry the Reviewed-by:'s you got in previous versions.
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