[lxc-users] Containers on linux-4.8-rc1 sometimes(?) requiring "cgmanager -m name=systemd" (bisected, but is it a bug?)

[Serge E. Hallyn]

On Tue, Sep 13, 2016 at 01:11:50AM -0700, Adam Richter wrote:
> On Linux 4.8-rc1 through 4-8-rc6 (latest rc), lxc fails start to
> Ubuntu 16.04 and Centos 7 containers [1], unless I first run
> "cgmanager -m name=systemd &" on the host, which, unlike the

Does starting lxcfs or installing the cgroupfs-mount package also
work?  Which hierarchy is failing to be mounted?  Is it the
name=systemd or a kernel one?

> containers, was not running systemd or cgmanager.

When you say "fails to start", at which point does it fail?  There are
two possibilities - (1) lxc or the lxc container config is asking for
new hierarchies to be mounted.  If that's the case, that should be fixed
to not balk when a not-mounted hierarchy can't be mounted.  Or (2) the
container init is trying to mount all the hierarchies.  In that case
I guess there's nothing we can do to help.