Comment 0 for bug 1944711

[impact]

restarting the systemd-logind service loses all existing sessions

[test case]

ubuntu@test-f:~$ loginctl list-sessions
SESSION UID USER SEAT TTY
   3789 1000 ubuntu pts/0

1 sessions listed.
ubuntu@test-f:~$ journalctl -b -u systemd-logind
-- Logs begin at Thu 2021-09-23 11:11:57 UTC, end at Thu 2021-09-23 11:22:55 UTC. --
Sep 23 11:22:51 test-f systemd[1]: Starting Login Service...
Sep 23 11:22:51 test-f systemd-logind[198]: New seat seat0.
Sep 23 11:22:51 test-f systemd[1]: Started Login Service.
Sep 23 11:22:52 test-f systemd-logind[198]: New session 3789 of user ubuntu.
ubuntu@test-f:~$ sudo systemctl restart systemd-logind
ubuntu@test-f:~$ journalctl -b -u systemd-logind
-- Logs begin at Thu 2021-09-23 11:11:57 UTC, end at Thu 2021-09-23 11:23:07 UTC. --
Sep 23 11:22:51 test-f systemd[1]: Starting Login Service...
Sep 23 11:22:51 test-f systemd-logind[198]: New seat seat0.
Sep 23 11:22:51 test-f systemd[1]: Started Login Service.
Sep 23 11:22:52 test-f systemd-logind[198]: New session 3789 of user ubuntu.
Sep 23 11:23:07 test-f systemd[1]: Stopping Login Service...
Sep 23 11:23:07 test-f systemd[1]: systemd-logind.service: Succeeded.
Sep 23 11:23:07 test-f systemd[1]: Stopped Login Service.
Sep 23 11:23:07 test-f systemd[1]: Starting Login Service...
Sep 23 11:23:07 test-f systemd-logind[469]: Failed to add user by file name 1000, ignoring: Invalid argument
Sep 23 11:23:07 test-f systemd-logind[469]: User enumeration failed: Invalid argument
Sep 23 11:23:07 test-f systemd-logind[469]: User of session 3789 not known.
Sep 23 11:23:07 test-f systemd-logind[469]: Session enumeration failed: No such file or directory
Sep 23 11:23:07 test-f systemd-logind[469]: New seat seat0.
Sep 23 11:23:07 test-f systemd[1]: Started Login Service.
ubuntu@test-f:~$ loginctl list-sessions
No sessions.

[regression potential]

any regression would likely occur during a systemd-logind restart, likely causing a loss of current login sessions.

[scope]

this is needed in f and earlier

this is fixed upstream by commit ac4e03d45bcf4ad2e570cabdb218e9bac003cc80 which is included in v246, so this is fixed in h and later already.