Re: [PATCH 11/11] blkcg: implement per-blkg request allocation

Vivek Goyal
2012-04-27T15:56:21Z

On Fri, Apr 27, 2012 at 08:51:40AM -0700, Tejun Heo wrote:
> On Fri, Apr 27, 2012 at 11:48:41AM -0400, Vivek Goyal wrote:
> > Not an unpriviliged malicious application. In typical cgroup scenario, we
> > can allow unpriviliged users to create child cgroups so that it can
> > further subdivide its resources to its children group. (ex. put firefox
> > in one cgroup, open office in another group etc.).
> >
> > So it is not same as jack up nr_requests.
>
> I find allowing unpriv users creating cgroups dumb. cgroup consumes
> kernel memory. Sans using kmemcg, what prevents them from creating
> gazillion cgroups and consuming all memories? The idea of allowing
> cgroups to !priv users is just broken from the get go.

Well creating a task consumes memory too but we allow unpriv users to
create tasks. :-)

May be a system wide cgroup limit will make sense?

Thanks
Vivek