Re: [Testing CGROUP inside CONTAINER]: BUG#2

["Serge E. Hallyn" <serue-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org>]

Quoting Rishikesh K. Rajak (risrajak-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org):
>     -  Execute the following command inside container
>      delta:~ # mkdir /cpu
>      delta:~ # mount -t cgroup -ocpu cgroup /cpu
> 
>     -   delta:~ # umount /cpu
>         delta:~ # mount
>             ...
>             cgroup on /cpu type cgroup (rw,cpu)
>             cgroup on /cpu type cgroup (rw,cpu)
>             cgroup on /cpu type cgroup (rw,cpu)
>         delta:~ # umount /cpu
>             umount: cgroup: not found
>             umount: /cpu: not mounted
>             umount: cgroup: not found
>             umount: /cpu: not mounted
>             umount: cgroup: not found
>             umount: /cpu: not mounted
>             umount: cgroup: not found
>             umount: /cpu: not mounted

This really sounds to me like a bug in your mount and
umount commands.  When I do those steps in a container,
just typing 'mount' no longer shows /cpu mounted.

(If I had to guess at something, I'd say you have
/etc/mtab linked to /proc/mounts, and something with
that is going wrong, but it could be not that)

Check /proc/self/mounts before and after each step,
compare to /etc/mtab.

And try doing mount -n and umount -n.

-serge