From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: CGroup Namespaces (v4) Date: Mon, 16 Nov 2015 17:37:58 -0500 Message-ID: <20151116223758.GM18894@mtj.duckdns.org> References: <1447703505-29672-1-git-send-email-serge@hallyn.com> <20151116204606.GA30681@mail.hallyn.com> <564A41AF.4040208@nod.at> <20151116205452.GA30975@mail.hallyn.com> <87y4dxh9b8.fsf@x220.int.ebiederm.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <87y4dxh9b8.fsf-JOvCrm2gF+uungPnsOpG7nhyD016LWXt@public.gmane.org> Sender: linux-api-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: "Eric W. Biederman" Cc: "Serge E. Hallyn" , Richard Weinberger , Richard Weinberger , LKML , "open list:ABI/API" , Linux Containers , LXC development mailing-list , cgroups mailinglist , Andrew Morton List-Id: linux-api@vger.kernel.org Hello, Eric. On Mon, Nov 16, 2015 at 04:24:27PM -0600, Eric W. Biederman wrote: > Does this allow mixing of cgroupfs and cgroupfs2? That is can I: "mount > -t cgroupfs" inside a container and "mount -t cgroupfs2" outside a > container? and still have reasonable things happen? I suspect the > semantics of cgroups prevent this but I am interested to know what happens. cgroup v1 and v2 are just separate hierarchies. They can't nest each other but co-existing and namespacing on their own is completely fine. The caveat is that a given controller can be on only one hierarchy but that's the same among v1 hierarchies too. Thanks. -- tejun