Comment 1 for bug 1955747

I have almost identical entries in my journalctl log, but I don't have the slowness that the OP is experiencing.

Dec 25 11:29:31 barley-cat sddm[718]: Authentication error: "Process crashed"
Dec 25 11:29:31 barley-cat sddm[718]: Auth: sddm-helper crashed (exit code 15)
Dec 25 11:29:31 barley-cat sddm[718]: Authentication error: "Process crashed"
Dec 25 11:29:31 barley-cat sddm[718]: Auth: sddm-helper exited with 15
Dec 25 11:29:31 barley-cat sddm[718]: Socket server stopping...
Dec 25 11:29:31 barley-cat sddm[718]: Socket server stopped.
Dec 25 11:29:31 barley-cat sddm[718]: Display server stopping...
Dec 25 11:29:31 barley-cat sddm[718]: Display server stopped.
Dec 25 11:29:31 barley-cat sddm[718]: Running display stop script "/usr/share/sddm/scripts/Xstop"
Dec 25 11:29:31 barley-cat sddm[718]: Removing display ":0" ...
Dec 25 11:29:31 barley-cat sddm[718]: Adding new display on vt 1 ...
Dec 25 11:29:31 barley-cat sddm[718]: Loading theme configuration from ""
Dec 25 11:29:31 barley-cat sddm[718]: Display server starting...
Dec 25 11:29:31 barley-cat sddm[718]: Adding cookie to "/var/run/sddm/{4c84cd71-7817-4c65-b807-344789cc5ab7}"
Dec 25 11:29:31 barley-cat sddm[718]: Running: /usr/bin/X -nolisten tcp -auth /var/run/sddm/{4c84cd71-7817-4c65-b807-344789cc5ab7} -background none -noreset -displayfd 18 -seat seat0 vt1
Dec 25 11:29:32 barley-cat sddm[718]: Setting default cursor
Dec 25 11:29:32 barley-cat sddm[718]: Running display setup script "/usr/share/sddm/scripts/Xsetup"
Dec 25 11:29:32 barley-cat sddm[718]: Display server started.
Dec 25 11:29:32 barley-cat sddm[718]: Socket server starting...
Dec 25 11:29:32 barley-cat sddm[718]: Socket server started.
Dec 25 11:29:32 barley-cat sddm[718]: Loading theme configuration from "/usr/share/sddm/themes/ubuntu-theme/theme.conf"
Dec 25 11:29:32 barley-cat sddm[718]: Greeter starting...
Dec 25 11:29:32 barley-cat sddm[718]: Signal received: SIGTERM
Dec 25 11:29:32 barley-cat sddm[718]: Socket server stopping...
Dec 25 11:29:32 barley-cat sddm[718]: Socket server stopped.
Dec 25 11:29:32 barley-cat sddm[718]: Display server stopping...
Dec 25 11:29:32 barley-cat sddm-helper[35033]: [PAM] Starting...
Dec 25 11:29:32 barley-cat sddm-helper[35033]: [PAM] Authenticating...
Dec 25 11:29:32 barley-cat sddm-helper[35033]: [PAM] returning.
Dec 25 11:29:33 barley-cat sddm[718]: Display server stopped.
Dec 25 11:29:33 barley-cat sddm[718]: Running display stop script "/usr/share/sddm/scripts/Xstop"
Dec 25 11:29:33 barley-cat sddm[718]: QProcess: Destroyed while process ("/usr/lib/x86_64-linux-gnu/sddm/sddm-helper") is still running.
Dec 25 11:29:33 barley-cat systemd[1]: sddm.service: Deactivated successfully.
Dec 25 11:29:33 barley-cat systemd[1]: sddm.service: Consumed 4min 2.222s CPU time.

Whether it matters, I'm running Kubuntu 22.04, fully updated.