fix /etc/xdg/autostart vs systemd race condition

phabricator-migrator · February 19, 2024, 5:47pm

Information

ID: 424
PHID: PHID-TASK-xsqvcnluesqlbbx7bad6
Author: Patrick
Status at Migration Time: open
Priority at Migration Time: Normal

Description

TLDR:

How to have a /etc/xdg/autostart/app.desktop service wait for a systemd service?

Long:

qubes-whonix-firewall.service runs enable-firewall and conditionally creates the /var/run/qubes-service/whonix-secure-proxy status file.

/etc/xdg/autostart/qubes-whonixsetup.desktop runs /usr/lib/qubes-whonix/qubes-whonixsetup. Sometimes /etc/xdg/autostart/qubes-whonixsetup.desktop runs faster than qubes-whonix-firewall.service. The status file does not exist at that point, which results in an “This TemplateVM needs a Whonix-Gateway NetVM” error popup.

I would like to avoid some sleep/wait/custom code if there is an existing tool for such purposes.

References:

A systemd --user instance knows nothing about the systemd --system instance. I.e. a systemd --user instance cannot reference After=some-system.service. Source:

https://lists.freedesktop.org/archives/systemd-devel/2017-February/038361.html

So we cannot use qubes-whonixsetup.service After=qubes-gui-agent.service.

systemd feature request - systemd --user instance ability to reference systemd --system services with After= etc.:

github.com/systemd/systemd

systemd --user instance ability to reference systemd --system services with After= etc.

opened 05:36PM - 26 Feb 17 UTC

closed 09:09PM - 26 Feb 17 UTC

adrelanos

RFE 🎁 pid1 duplicate

### Submission type - [x] Request for enhancement (RFE) ### systemd vers…ion the issue has been seen with > 232 ### Used distribution Debian ### feature request #### use case Converting `/etc/xdg/autostart/app.desktop` (graphical autostart applications) to `systemd --user` services. In Qubes, graphical applications must start `After=qubes-gui-agent.service` (a `systemd --system` service). But not necessarily any service to be converted from `/etc/xdg/autostart/app.desktop` to a systemd unit needs that. #### suggestion A useful feature would be if systemd unit file running under a `systemd --user` instance could reference `After=some-system.service`.

Comments

Patrick

2015-11-05 16:57:18 UTC

marmarek

2015-11-05 18:43:04 UTC

Patrick

2015-11-05 19:01:37 UTC

Patrick

2015-11-05 19:05:07 UTC

Patrick

2015-11-12 13:32:50 UTC

Patrick

2016-04-05 15:41:09 UTC

HulaHoop

2016-04-05 23:16:23 UTC

Patrick

2016-04-06 01:04:02 UTC

Patrick

2016-04-07 19:16:46 UTC

Patrick

2016-04-15 18:17:27 UTC

Patrick

2017-02-20 23:56:32 UTC

One step closer.

By Debian stretch default, there are some default systemd user unit files in /usr/lib/systemd/user/.

/usr/lib/systemd/user/mytest.service:
[Unit]
Description=mytest

[Service]
Type=oneshot
RemainAfterExit=yes
ExecStart=/bin/true

[Install]
WantedBy=default.target
systemctl --user enable mytest
Worked for me.

Created symlink /home/user/.config/systemd/user/default.target.wants/mytest.service → /usr/lib/systemd/user/mytest.service.

I haven’t figured out yet how to cleanly (or uncleanly) enable systemd user services using Debian packaging. sudo -u user systemctl --user enable mytest will probably not work (apt-get somehow does not like sudo -u user anymore since Debian stretch), and that would not be a clean solution either.

Patrick

2017-02-21 00:13:42 UTC

Patrick

2017-02-21 00:23:44 UTC

Patrick

2017-02-21 16:54:07 UTC

Patrick

2017-02-26 17:53:26 UTC

Patrick

2017-02-28 01:11:14 UTC

Patrick

2017-03-01 21:05:50 UTC

! In T424#12530, @Patrick wrote:
A systemd --user instance knows nothing about the systemd --system instance. I.e. a systemd --user instance cannot reference After=some-system.service. Source:

[systemd-devel] Can a systemd --user instance rely on After= of systemd --system instance?

So we cannot use qubes-whonixsetup.service After=qubes-gui-agent.service.

systemd feature request - systemd --user instance ability to reference systemd --system services with After= etc.:
systemd --user instance ability to reference systemd --system services with After= etc. · Issue #5462 · systemd/systemd · GitHub

/lib/systemd/system/user@.service does ExecStart=-/lib/systemd/systemd --user. In theory we could add a systemd drop-in adding: After=qubes-gui-agent.service but that looks like an awful hack.

ExecStartPre=systemctl --user import-environment also looks like an awful hack. Doing something as the distribution that should really be only done by the user.

Given all these issues referenced above, I don’t think systemd is ready to replace /etc/xdg/autostart. We’ll probably need to wait until the X (or by that time perhaps wayland) session gets started by the systemctl --user session.

Rechecking the status of systemd’s capabilities at a later release.