lxc-start: Device or resource busy - failed to remove previous cgroup

[Serge E. Hallyn]

Quoting Dwight Schauer (dschauer at gmail.com):
> On Mon, Jan 4, 2010 at 7:24 PM, Serge E. Hallyn <serue at us.ibm.com> wrote:
> > tasks is empty, but there are subdirectories - 102, 26533, etc.
> > This looks like the dirtywork of the ns cgroup.  If each of those
> > subdirs is also empty then you can rmdir them, then rmdir /cgroup/arch64-1.
> >
> > Or, use a release agent, which is what I do.
> >
> > cat << EOF > /bin/remove_dead_cgroup.sh
> > #!/bin/sh
> > echo "Removing dead cgroup .$*." >> /var/log/cgroup
> > rmdir /cgroup/$* >> /var/log/cgroup 2>&1
> > echo "return value was $?" >> /var/log/cgroup
> > EOF
> > echo /bin/remove_dead_cgroup.sh > /cgroup/release_agent
> > echo 1 > /cgroup/notify_on_release
> >
> 
> well, In my case those numbered subdirectories are empty, and I can't
> remove the files in them as root even with -f.
> 
> I'll try with a newer kernel.

By 'they are empty' you mean no tasks listed in their tasks file?
What files are you trying to rm -f?  So long as there are no further
cgroup subdirectories, just rmdir each directory - the cgroupfs files
can't be deleted by hand, it's true.

-serge