No "New Login" for user with Desktop effects enabled

[Carsten Schneemann]

Binary package hint: gdm

When using Applications --> System Tools --> New Login to create a new login screen, users with Desktop effects enabled cannot log in. For users with Desktop effects disabled, everything works as usual.

How to reproduce:
0. Enable Desktop effects for user X.
1. Log in as user Y.
2. Select Applications --> System Tools --> New Login.
3. Try to log in as user X.

In this case, instead of being logged in, I get a white screen on which I can see & move the mouse pointer. The session can be exited as usual with CTRL+ALT+Backspace, returning me to the session of user X.
The same thing happens if user Y initially has desktop effects switched off and switches them on during a session initiated with Applications --> System Tools --> New Login.

I'm running Feisty on an IBM ThinkPad T41p with the free "Radeon" driver (xserver-xorg-video-ati, i.e. not fglrx).

[Travis Watkins (amaranth)]

Our wrapper script needs to check if you can use can do 3d acceleration before starting compiz since only the first X server (user session) can do 3d but will get past our other checks.

[Brett Alton (brett-alton-deactivatedaccount)]

I had this problem when I kept the personal configuration files from 7.10 Tribe 2 and formatted down to 7.04. I had desktop effects enabled on 7.10 so it tried to force the settings in 7.04 but a white screen came up with the mouse cursor as described above...

Hope that gives another situation to wrap your head around the problem...

[Martin Pitt (pitti)]

Travis, is it actually posible to detect this condition reliably? If not, we should maybe only enable compiz on display :0?

[Michael Vogt (mvo)]

Thanks for your bugreport.

I can not reproduce this issue here, can you please attach the file ~/.xsession-errors to this bugreport after a unsuccessful login attempt?

Thanks,
Michael

[Martin Pitt (pitti)]

This is not reproducible in Gutsy, thus likely fixed already (it automatically falls back to metacity on the second X screen now).

If it still happens for you in gutsy, please report here, and we will reopen the issue. Thank you for your report!

[Matthew Gregg (mcg)]

Not sure if this should be a new bug or not so here goes.....

In Gutsy+Nvidia with Compiz enabled for the active user, if a second user logs in(no compiz) and the session is switched back to the originating compiz enabled user, the compiz session will be hung with a black screen.

[Shane O'Connell (shaneoc)]

I don't think this bug is fixed.. I am having an issue very very similar to this problem, although I don't know what this "New Login" thing is, it's not in my System Tools.

When switching between users if I switch to a user who is already logged in and has compiz enabled, the gnome-screensaver password box is not visible and all I see is a white screen. I can only see the mouse. If I move the mouse to where the password box should be, the cursor changes to the horizontal line which means I can type things. I can then type my password in and log in fine.

I am running gutsy, with an nvidia card. My problem seems identical to bug #113557, but that bug was marked as a duplicate of this one.

[Thomas Wojcik (tomwoj)]

Just for information if it can help :
if I disable in "User switcher preferences" the "Lock the screen after switching users" (for each user) I get no more the white screen issue.

Gutsy+Nvidia with Compiz enabled.

[Luke12 (luca-venturini)]

Same issue, Gutsy with Nvidia and Compiz enabled. When switching back to first user session I am welcomed by a white screen. HOWEVER, I am still able to get into user X session. I just have to type the password and press the "Enter" button to log in - so it is just a rendering bug, IMHO, and luckily, the password box is already selected by default.

[Julian Alarcon (julian-alarcon)]

Maybe some one is refering to this another bug:
https://bugs.launchpad.net/ubuntu/+source/linux-restricted-modules-2.6.24/+bug/160264