Bug#803013: systemd should not destroy application created cgroups

[Paul Szabo]

Dear Martin,

> You can create a drop-in like
> /etc/systemd/system/cgred.service.d/delegate.conf
> with
> 
> [Service]
> Delegate=yes

I tried that, but did not help; also did not help to do similar with
file named
   /etc/systemd/system/cgrulesengd.service.d/delegate.conf
matching name of running daemon. Anything else you suggest to try?

My guess is that the above could not possibly help. It may tell systemd
that cgrulesengd will do weird things and to leave alone, but it does
not tell what to leave alone. How could systemd guess that cgrulesengd
will write things into /sys/fs/cgroup/cpu,cpuacct/ and to leave those?

I think this issue is a "true bug" in systemd, that it should not use
empty (zero-length) string pto "path to" values in cg_migrate() calls:
it seems an oversight to have assert(pto) but no assert(strlen(pto))
sanity checks in the code.
Maybe I should check where calls with empty strings originate from ...

Cheers, Paul
-- 
Paul Szabo   psz at maths.usyd.edu.au   http://www.maths.usyd.edu.au/u/psz/
School of Mathematics and Statistics   University of Sydney    Australia