[hardy] GDM hangs on a black screen upon startup

[Tomas Cassidy]

Binary package hint: gdm

System: Mythbuntu 8.04 with autologin enabled (default for mythbuntu)
GPU: nVidia 8600GT

Sometimes when I startup the computer it hangs on a black screen and doesnt appear to login. The mouse appears and can be moved around, but nothing else happens. I can get the autologin to occur by going to the VC at Ctrl+Alt+1 and running /etc/init.d/gdm restart.

[Michael R. Head (burner)]

I think I saw this, too.

In my case, I could see the beige background and the circular timer mouse cursor spinning indefinitely. I went to a text console and ran top. I saw that gdmgreeter was monopolizing the CPU. I editied gdm.conf and switched to gdmlogin, restarted gdm and all was well (though gdmgreeter probably shouldn't be spinning like this).

I didn't find anything apparently relevant in the gdm log, syslog, or Xorg.0.log.

I reboot fairly often on my dual boot laptop. I have all the latest updates as of april 1, I use the nvidia binary driver, and have a T61p laptop with a Quadro FX 570M video chip.

[Michael R. Head (burner)]

This _might_ have to do with sound, now that I think about it.

[Michael R. Head (burner)]

OK, my problem was actually bug #210538 sorry for hijacking your bug, Tomas.

[Sebastian Kapfer (caci)]

Confirmed. gdmgreeter consuming 100% CPU for several minutes, then suddenly the login graphics come up and everything works as usual.

[Sebastian Kapfer (caci)]

When you attach strace to gdmgreeter, you see that it's madly scanning the same files over and over again (just the open calls are shown here):

open("/opt/cip/share/gdm-greeter/gtk-2.0/gtkrc", O_RDONLY|O_LARGEFILE) = 5
open("/usr/share/themes/Human/gtk-2.0/gtkrc", O_RDONLY|O_LARGEFILE) = 5
open("/usr/lib/gtk-2.0/2.10.0/engines/libubuntulooks.so", O_RDONLY) = 6
open("/opt/cip/share/gdm-greeter/gtk-2.0/gtkrc", O_RDONLY|O_LARGEFILE) = 5
open("/usr/share/themes/Human/gtk-2.0/gtkrc", O_RDONLY|O_LARGEFILE) = 5
open("/usr/lib/gtk-2.0/2.10.0/engines/libubuntulooks.so", O_RDONLY) = 6
open("/opt/cip/share/gdm-greeter/gtk-2.0/gtkrc", O_RDONLY|O_LARGEFILE) = 5
open("/usr/share/themes/Human/gtk-2.0/gtkrc", O_RDONLY|O_LARGEFILE) = 5
open("/usr/lib/gtk-2.0/2.10.0/engines/libubuntulooks.so", O_RDONLY) = 6
open("/opt/cip/share/gdm-greeter/gtk-2.0/gtkrc", O_RDONLY|O_LARGEFILE) = 5
open("/usr/share/themes/Human/gtk-2.0/gtkrc", O_RDONLY|O_LARGEFILE) = 5
open("/usr/lib/gtk-2.0/2.10.0/engines/libubuntulooks.so", O_RDONLY) = 6
open("/opt/cip/share/gdm-greeter/gtk-2.0/gtkrc", O_RDONLY|O_LARGEFILE) = 5
open("/usr/share/themes/Human/gtk-2.0/gtkrc", O_RDONLY|O_LARGEFILE) = 5
open("/usr/lib/gtk-2.0/2.10.0/engines/libubuntulooks.so", O_RDONLY) = 6
open("/opt/cip/share/gdm-greeter/gtk-2.0/gtkrc", O_RDONLY|O_LARGEFILE) = 5
open("/usr/share/themes/Human/gtk-2.0/gtkrc", O_RDONLY|O_LARGEFILE) = 5
open("/usr/lib/gtk-2.0/2.10.0/engines/libubuntulooks.so", O_RDONLY) = 6
open("/opt/cip/share/gdm-greeter/gtk-2.0/gtkrc", O_RDONLY|O_LARGEFILE) = 5
open("/opt/cip/share/gdm-greeter/gtk-2.0/gtkrc", O_RDONLY|O_LARGEFILE) = 5
open("/usr/share/themes/Human/gtk-2.0/gtkrc", O_RDONLY|O_LARGEFILE) = 5
open("/usr/lib/gtk-2.0/2.10.0/engines/libubuntulooks.so", O_RDONLY) = 6
open("/opt/cip/share/gdm-greeter/gtk-2.0/gtkrc", O_RDONLY|O_LARGEFILE) = 5
open("/usr/share/themes/Human/gtk-2.0/gtkrc", O_RDONLY|O_LARGEFILE) = 5
open("/usr/lib/gtk-2.0/2.10.0/engines/libubuntulooks.so", O_RDONLY) = 6
open("/opt/cip/share/gdm-greeter/gtk-2.0/gtkrc", O_RDONLY|O_LARGEFILE) = 5
open("/usr/share/themes/Human/gtk-2.0/gtkrc", O_RDONLY|O_LARGEFILE) = 5
open("/usr/lib/gtk-2.0/2.10.0/engines/libubuntulooks.so", O_RDONLY) = 6
open("/opt/cip/share/gdm-greeter/gtk-2.0/gtkrc", O_RDONLY|O_LARGEFILE) = 5
open("/usr/share/themes/Human/gtk-2.0/gtkrc", O_RDONLY|O_LARGEFILE) = 5

[Sebastian Kapfer (caci)]

The effect is caused by .gtkrc included in our theme (located in /opt/cip...). I'm now circumventing it by using the gtkrc from the Human theme. To reproduce, you can use e.g. the gtkrc from the Glossy theme, under /usr/share/themes/Glossy/gtk-2.0/gtkrc.

[Sebastien Bacher (seb128)]

the gtkrc issue is bug #147045, it's not clear though that the bug described is the same issue, why did you comment there rather than opening a new bug about your issue?

[Sebastian Kapfer (caci)]

Frankly, I had no idea it was a GTK issue. I get the same results as the reporter #203825, GTK stops my login screens from popping up. Interestingly, they /do/ pop up given enough time (~2-3 minutes at 100% CPU).

I'll try to get a backtrace of my bug tomorrow, but I think the two can be merged. If this bug happens to be triggered by any GDM themes Ubuntu distributes (as opposed to our homebrewn), the severity of #147045 should probably be raised, as it at first glance stops users from logging in.

[Sebastien Bacher (seb128)]

that's an issue only when using a theme using gtkrc coloring, the ubuntu humanlist theme had the issue and has been workarounded some days ago, there is no theme installed on a stock ubuntu having this issue

[Sebastien Bacher (seb128)]

could you try using an another theme?

[Tomas Cassidy (tomas-cassidy)]

I haven't noticed this problem occurring since the default theme was changed from the blue to the black theme.

[Tomas Cassidy (tomas-cassidy)]

I noticed the problem occurring again after the mythtv theme was changed from the black back to the blue theme. mythubntu is still running the black theme by default. when the problem occurs, I switch to a VC and run 'top', but it doesn't show any process consuming large amounts of CPU or RAM.

[Zdeněk Dlauhý (zdlauhy)]

Two days ago I experinced something same. And today also gdm wont start.
I do not know, if this is same bug, but i have same black screen when run the PC.

I use Sys Rq and restarted pc and GDM apears okay.

i have nvidia-glx-new driver a and Hardy

[stephenb (stephenb-snu)]

I am having the same problem. But first I get the notorious xsessions login error message. That goes away after a few seconds, then I get the black screen with the x cursor.

The following seems to occur around the time it happens:

May 30 21:23:14 server1 gdm[9367]: Gtk-WARNING: Ignoring the separator setting

... [some time out messages regarding nfs mounts] . . . <-- could this be why?

Then I think this happens when I hit Ctrl + Alt + Backspace:

May 30 21:25:39 server1 gdm[6456]: WARNING: failsafe dialog failed (inhibitions: 0 0)
May 30 21:25:39 server1 kernel: [ 264.543047] [fglrx] interrupt source 10000000 successfully disabled!

 . . . [some other fglrx lines] . . .

May 30 21:25:39 server1 gdm[9987]: Gtk-WARNING: cannot open display: :0
May 30 21:25:40 server1 gdm[6456]: WARNING: failsafe dialog failed (inhibitions: 0 1)
May 30 21:25:39 server1 gdm[9987]: Gtk-WARNING: cannot open display: :0
May 30 21:25:40 server1 gdm[6456]: WARNING: failsafe dialog failed (inhibitions: 1 1)
May 30 21:25:40 server1 gdm[6459]: WARNING: gdm_slave_xioerror_handler: Fatal X error - Restarting :0
May 30 21:25:42 server1 kernel: [ 266.860543] firegl1.isse.53[10023]: segfault at c rip 4a6dcf39 rsp ff865580 error 4
May 30 21:25:42 server1 kernel: [ 266.861507] firegl1.isse.53[10024]: segfault at c rip 4a6dcf39 rsp ffce7a00 error 4

I do Ctrl + Alt + Backspace to get back to the login. When I login in again, everything is fine.

[stephenb (stephenb-snu)]

Sorry, can't see where to edit previous comments.

So, the second "Gtk-WARNING: cannot open display: :0" shown above should be gdm[9989] not gdm[9987]

[stephenb (stephenb-snu)]

Also, I'd like to add that I've found I only get this problem after installing fglrx according to these instructions on the Unofficial ATI Linux Driver Wiki:

    http://wiki.cchtml.com/index.php/Ubu...allation_Guide

Following these instructions is the only way I can get a working fglrx driver.

However, if I use the regular Ubuntu xorg repositories for fglrx, it doesn't happen. But then I am left with Mesa OpenGL rendering, which doesn't work will for me.

[Sebastien Bacher (seb128)]

seems to be a closed source binary driver issue and not an ubuntu one then, you should contact ati about the issue

[Pedro Villavicencio (pedro)]

closing this report then.

[Sebastian Kapfer (caci)]

This happens on nvidia too. Nothing to do with the driver.

[Sebastian Kapfer (caci)]

The original bug report was about a GTK bug, not about a segfaulting closed source driver. Please reopen, as the original issue is not fixed and valid.

Sorry for the spam.