kde-4.0.3 breaks auto-login

[Tony Green]

Binary package hint: kdm-kde4

System: 64-bit Kubuntu 7.10

Yesterday I installed the latest updates to KDE4 (which Adept Notifier prompted me to do) and since doing that, KDE3's automatic login no longer works. This means that when I switch my computer on, I am no longer automatically logged in but have to do so manually.

After investigation, I have found that the reason for this is that the new release changes the default display manager from the kdm from KDE3 to that from KDE4, so the startup parameters I have set are now ignored.

An option would have been to enable auto-login under KDE4, but since the system settings application under KDE4 doesn't yet have an "administrator mode" button and kcontrol doesn't seem to exist under KDE4, this is impossible.

I have managed to manually restore the old display manager (instructions below in case anybody comes to this but wondering how to) but I think that over-riding the existing display manager when it's not possible to configure the new one properly yet is going to cause a lot of problems to Kubuntu users.

** How to restore the system to kdm from KDE3 **
Run: sudo dpkg-reconfigure kdm
Hit Enter
Select kdm rather than kdm-kde4
Hit Enter

This replaces the necessary init file so that the correct kdm will try to start.
...but... there's a bug in the reconfiguration process, so you also need to edit /etc/X11/default-display-manager (as root) to read
/usr/bin/kdm

[Harald Sitter (apachelogger)]

You should have been asked while upgrading which display manager you want to use. Was this the case? If not it is a bug, but I can't really imagine where it would be caused.

[Tony Green (ubuntu-beermad-deactivatedaccount)]

Sorry, no I didn't get asked which display manager I wanted. At least - I don't <i>remember</i> having been asked; I don't think I'd have gone for the new one if I had, as KDE3's still more usable at present. It seems to have gone ahead and made the change of its own accord.

I presume the problem must be the kdm install just going ahead and making the change without asking.

Strange thing was that when I ran dpkg-reconfigure kdm, it put the old kdm link back in /etc/rc2.d but didn't touch /etc/X11/default-display-manager and it left the kdm-kde4 link in /etc/rc2.d - I don't know if that's symptomatic of a deeper problem...

[Tony Green (ubuntu-beermad-deactivatedaccount)]

As an experiment, I just tried removing and then re-installing kdm-kde4 through Adept manager.

I DID get a dialogue asking which display manager I wanted to use on this occasion. The default option is kdm rather than kdm-kde4, which means the problem wouldn't have been due to me accidentally replying to the dialogue (as sometimes happens if one pops up when I'm typing) since that would have left the old display manager set up.

I wonder if for some reason the dialogue is suppressed when the install is invoked from the notifier? That's trickier for me to test without having the previous version installed :-(

[Harald Sitter (apachelogger)]

Possible, if it is upgrading, but then it probably would still use the default, which is kdm.

[Gijs Peek (gijs-peek)]

It is possible to enable autologin in kdm-kde4 by invoking kde systemsettings with 'sudo /usr/lib/kde4/bin/systemsettings'. However, autologin doesn't work: when I enable autologin I just get a 'login failed' message when kdm starts.

[Drossos Stamboulakis (adsluard)]

I can also confirm that autologin doesn't work even when running systemsettings as root.

When you next startup and attempt an autologin, it fails to authenticate. Is this a problem with permissions (PAM?) or with kdm4?

Since I can only see this is a problem in ubuntu, it's probably a permissions issue?

[Tony Green (ubuntu-beermad-deactivatedaccount)]

I can now confirm that installing KDE4 is DEFINITELY changing the default display manager without asking.

I had removed all of the KDE4 packages as it was nowhere near ready for use. With the KDE4.1 betas being released, I decided to give it another try and without any interaction at all, it rewrote /etc/X11/default-dispay-manager.

Worse still, after manually editing that file back to use the correct display manager, I installed the updated packages that were presented to me this morning. AND IT OVER-WROTE THE FILE AGAIN!

[Harald Sitter (apachelogger)]

Auto-login works properly in Kubuntu Intrepid