> > If root is actually logged in and has a personal user manager running, > is there really a use case for this? Yes, the most obvious one is ssh agent for root itself. The agent that you want to start when you login as root, and stop when you logout.
> Does a "personal user manager" for > root provide any additional privilege separation or security? It usually doesn't. I agree that it can be bad for security if poorly handled. > Also (for comparison) I *think* in systemd world a user instance is only > for uid > 1000 (with the assumption that uid<1000 are system users). I verified it on arch linux. It spawns a service manager when I login as root. However, both pipewire.socket and pipewire.service have the line: `ConditionUser=!root` that prevents it from being used as root. I pasted the logs below. Overall, there are 2 choices for security: 1. Use UID_MIN and not spawn per-user service manager 2. Define all "unsafe" services as "not launchable as root". Personally, I prefer option 1, because I don't have that use case. But I think user/distro should care about it, not s6-frontend. ``` [user@PC-0 ~]$ systemctl status [email protected] * [email protected] - User Manager for UID 0 Loaded: loaded (/usr/lib/systemd/system/[email protected]; static) Drop-In: /usr/lib/systemd/system/[email protected] `-10-login-barrier.conf Active: active (running) since Fri 2026-09-11 13:22:21 +05; 24min ago Invocation: a163a1c92d904205c45328f20a109339 Docs: man:[email protected](5) Main PID: 5899 (systemd) Status: "Ready." Tasks: 4 Memory: 5.5M (peak: 10.1M) CPU: 247ms CGroup: /user.slice/user-0.slice/[email protected] |-init.scope | |-5899 /usr/lib/systemd/systemd --user | `-5901 "(sd-pam)" `-session.slice `-dbus-broker.service |-9673 /usr/bin/dbus-broker-launch --scope user `-9674 dbus-broker --log 11 [truncated] [user@PC-0 ~]$ sudo systemctl --user -M [email protected] status pipewire.socket * pipewire.socket - PipeWire Multimedia System Sockets Loaded: loaded (/usr/lib/systemd/user/pipewire.socket; enabled; preset: enabled) Active: inactive (dead) Triggers: * pipewire.service Condition: start condition unmet at Fri 2026-09-11 13:22:21 +05; 22min ago `- ConditionUser=!root was not met Listen: /run/user/0/pipewire-0 (Stream) /run/user/0/pipewire-0-manager (Stream) [user@PC-0 ~]$ sudo journalctl --user -M [email protected] -u pipewire.socket -- Boot 729b687550124b9d95a87515ae226015 -- Sep 11 13:22:21 PC-0 systemd[5899]: PipeWire Multimedia System Sockets skipped,unmet condition check ConditionUser=!root ``` On Fri, Sep 11, 2026 at 1:10 PM Lorenzo <[email protected]> wrote: > > Hello, > > On Mon, 7 Sep 2026 17:31:47 +0500 > username <[email protected]> wrote: > > > > > Root makes the implicit model more confusing. > > > > If root is actually logged in and has a personal user manager running, > > is there really a use case for this? Does a "personal user manager" for > root provide any additional privilege separation or security? Any other > use case? > Also (for comparison) I *think* in systemd world a user instance is only > for uid > 1000 (with the assumption that uid<1000 are system users). > > To summarize, I thought there was not a use case for "root personal user > manager" so I'm interested in reading a use case example of it. > > Best Regards, > Lorenzo
