[Debian-eeepc-devel] Weird behavior with display

[Ernesto Domato]

On Mon, Nov 2, 2009 at 06:55, Alan Jenkins
<sourcejedi.lkml at googlemail.com> wrote:
> On 11/1/09, Ernesto Domato <edomat at gmail.com> wrote:
>> Hi, I have a 901 running sid with the Gnome window manager.
>
> <nitpick>You mean desktop environment.  The window manager is called
> metacity</nitpick>
>

Yes, sorry for the mistake, I mean Gnome desktop environment.

>  Since the
>> last upgrade, I'm having a weird behavior with the display that if I
>> shutdown the computer while logged on a Gnome session, the display
>> goes black all the shutdown process
>
>> and when I turn on the computer
>> again it keeps black till the end of the boot process that remains
>> black till I log on on the Gnome session again. The black screen is
>> even with the Asus pre-boot screen.
>
> Are you actually saying you have to type
>
> "username <enter>"
> "password <enter">"
>
> *at a black screen*, before you can see anything at all on the screen?
>

Yes, exactly that. Other behavior is that when it ends booting and
before login into the system, if I change to a console (with
Ctrl+Alt+F1 for example), the screen shows the console for less than a
second and goes black again and if I go back to the GDM screen (with
Ctrl+Alt+F7) it tries to show the GDM screen for less than a second
before going black again.

> It seems more likely that the first thing you see is the GDM login
> screen.  IOW, it seems more likely that the blackscreen condition is
> fixed as soon as the X server is started.
>

Not really, the X server is loaded before the GDM login screen that
use it so the display is fix after X server is loaded and when login
to the Gnome desktop environment.

> I have absolutely no idea.  I would call it a bug in X that it could
> leave your system in this state - unless there is some other program
> screwing with the video hardware at the same time, which really isn't
> on.
>

I think is not a X bug or at least a direct X bug, I think that may be
something else that screw the video mode that let the hardware in this
strange state. Remember that when I turn on the computer after this
happens I don't see even the Asus screen at the beginning.

> Have you configured your system to use a graphical framebuffer
> console?  (If you don't know what I mean, the answer is no. If you do
> know what I mean, the question is why you haven't tried disabling it
> already :-).  Note that "I enabled kernel mode setting" also counts as
> a "yes").
>

No. Is just a fresh Debian installation and upgraded to Sid.

> One thought that comes to mind is that it could be a problem with the
> brightness setting for the backlight... it might be worth having a
> bash at the brightness keys when you have a black screen.
>

No, is not a brightness problem, it seems like if the display turned off.

> Do you use an external monitor at all?  Do you run a special applet or
> something for it?
>

No, I'm running any applet for the display either,

> Here are a few things I might try if it happened to me:-
>
> 1) I assume "shutdown while logged into a gnome session" means the
> obvious "use the gnome GUI to shutdown the computer".
>

Yes.

> a) What happens if you run "halt" from a gnome terminal instead?
>

It works in the sense that it kills all so it shows the console before
shutting down and when I power on the computer again it works as
expected (I see the Asuss screen, Grub menu and GDM screen). So, it
seems to be something related with the normal way to shutting down the
computer from the Gnome desktop environment.

> c) What happens if, after logging into gnome, you switch to a console
> (i.e. ctrl+alt+f1), login and run "halt"?
>

Off course it works the same way as point (a) :-)

> I wouldn't suggest you try installing KDE, but as a last resort you
> might play with installing KDM.  I seem to remember from experience
> that the desktop environments have standardised the interface for the
> login manager, so that you may be able to invoke shutdown from a gnome
> session even if you run KDM instead of GDM.
>

I refuse to do this at this moment because of the huge amount of
dependencies for just the KDM ;-)

Anyway, right now it's working well when I shutdown from the Gnome
desktop environment so the behavior seems to happen randomly or if not
randomly at very specific situations that I have to find out.

Thanks,
Ernesto.