Comment # 8 on bug 1183247 from Bernd Wachter

I've hit this same issue when testing if we can start upgrading some systems to
15.3. Libvirt version there also is 7.1.0. When forcing only v2 cgroup
hierarchy I can start a container, though still have other issues making it
unusable:

# virsh -c lxc:// lxc-enter-namespace www1-de --noseclabel /usr/bin/bash
libvirt: Cgroup error : Unable to write to
'/sys/fs/cgroup/machine.slice/machine-lxc\x2d1712\x2dwww1\x2dde.scope/cgroup.procs':
Device or resource busy
error: internal error: Child process (27649) unexpected exit status 125