With RHEL7 it was known that restarting dbus service was causing delays in logins, because pam_systemd was timing out after 25 seconds.
With RHEL8 this was fixed, because systemd-logind was restarting automatically.

I thought such issue was fixed with RHEL9 but apparently not. It's even worse: pam_systemd now hangs for 120 seconds!

The root cause for this is, when restarting dbus, systemd-logind disconnects from DBus but never reconnects, causing DBus service to remain activatable forever:

# busctl | grep login1
org.freedesktop.login1                    - -               -       (activatable) -                      -       -

Please harden systemd-logind behavior, it's really important to have something robust here.

Reproducer

# systemctl restart dbus
# time ssh localhost true
real	2m1.819s
user	0m0.021s
sys	0m0.026s