Hang with fair cgroup scheduler (reproducer is attached.)

[kamezawa.hiroyu at jp.fujitsu.com]

>> just to be sure SMP does matter here (most likely yes, I guess).
>> 
>
>NUMA? I am not able to reproduce it here locally on an x86 8 CPU box.
>
yes. I used NUMA. 2 Nodes/4CPU x 2

Hmm..

Thanks,
-Kame