Re: [PATCH] sched/deadline: Skip overflow check if 0 capacity

[Waiman Long]

On 11/8/24 11:31 AM, Juri Lelli wrote:
> That said though, I believe I just found an additional issue. With the
> above the system doesn't crash (it did w/o it), but happily moves
> DEADLINE tasks out of a domain with a single CPU going offline. Last
> time I looked at this we were properly checking and failing the hotplug
> operation, but it was indeed a while ago, so not sure yet what changed.
> More staring.
>
> Oh, so broken, yay. 🙂

Is it the case that the null total_bw bug let the cpu offline succeeds 
in a 1-cpu partition with a DL task and cause it to crash? I am also OK 
if you adds the check for the presence of a DL task in the cpu and fails 
the offline check in this case.

Thanks,
Longman