Messed up Login in KDE

[luxifer]

Hi there,

I've messed up my login system and exhausted my ideas on how to fix it. Here's what happened:

I have upgraded from KDE 4 (stable) to KDE 5 (kde overlay) last weekend but it turned out I didn't like it because quite some things I'm used to just didn't work as expected or at all. So I've decided to downgrade to KDE 4 again. After going through dependency hell I managed to remove any KDE 5 (and kde overlay) packages again and downgrade to their KDE 4 parts (where applicable). Everything went fine.

"emerge -avuND --newrepo --keep-going=y --with-bdeps=y world" shows no packages to merge
"emerge -av @preserved-rebuild" shows no packages to merge
"revdep-rebuild" shows no packages to merge

all KDE 5 packages are gone

However: I cannot log in using KDM (VT works fine) - it acts as if I entered the wrong password. I also cannot unlock my session once I have locked it with the KDE screenlocker.

kdm.log holds those lines upon a login try:
klauncher(4496) kdemain: No DBUS session-bus found. Check if you have started the DBUS server.
kdeinit4: Communication error with launcher. Exiting!
kdmgreet(4487)/kdecore (K*TimeZone*): KSystemTimeZones: ktimezoned initialize() D-Bus call failed: "Not connected to D-Bus server"

I have done emerge "$(qlist -IC dbus)" and emerge "$(qlist -IC polkit)" to no avail. DBUS and Polkit are running.

I'm using systemd if that helps.

[luxifer]

problem solved - thread can be closed, kthxbye

to whom it may concern: problem eventually boiled down to missing /etc/pam.d/kde - despite(!) kdebase-pam being re-emerged at least once! linking /etc/pam.d/lightdm to /etc/pam.d/kde did the trick for me