Bug#787758: 'Failed at step NAMESPACE spawning' when using ReadOnlyDirectories in multi-instance service file

[nusenu]

Package: systemd
Version: 215-17

when using a multi-instance systemd service file with
ReadOnlyDirectories the service fails if it is attempted to start on a
Debian 8 system that has been upgraded from a previous release.

Error message is:
Failed at step NAMESPACE spawning /usr/bin/tor: No such file or directory
service: main process exited, code=exited, status=226/NAMESPACE

The same config works on a fresh Debian 8 installation.

This problem has been discussed on systemd-devel [2], but since this
appears to be debian (upgrade) specific I'm filing this here.


[1]
https://github.com/nusenu/ansible-relayor/commit/4f6283e6d993e6f81a632007c823797253feee38

Note in upstream bugtracker:
https://bugs.freedesktop.org/show_bug.cgi?id=89875#c2

[2]
http://lists.freedesktop.org/archives/systemd-devel/2015-April/031377.html
http://lists.freedesktop.org/archives/systemd-devel/2015-May/031993.html
http://lists.freedesktop.org/archives/systemd-devel/2015-May/031995.html
http://lists.freedesktop.org/archives/systemd-devel/2015-June/032779.html

[3] https://github.com/nusenu/ansible-relayor/issues/16