Re: [gdm-list] FailsafeXServer - gdm keeps restarting X

[Brian Cameron <Brian Cameron Sun COM>]

Bryce:

I think what GDM is assuming that the "failsafe X server" will start
up an Xserver that it can run the greeter on.  It seems like you
want GDM to do something else.  I think you probably need to hack
the code to make it avoid trying to manage the display after
starting the Xserver script.  Perhaps a configuration option could
be added so that you could more easily configure GDM to work this
way.

Brian

> On Thu, Aug 30, 2007 at 05:23:24PM -0700, Mike Oliver wrote:
> > Bryce Harrington wrote:
> > > I've tried it both with and without the '&' without any change of
> > > effect.  I left it in since the example you pointed to had one but I
> > > think it is unnecessary.
> > Leave the '&' there, otherwise the 'sleep' and 'kill' won't
> > execute until after the 'xinit' has terminated.
> >
> > Try adding a 'wait' after the 'kill' so that your failsafe
> > script does not exit until the 'xinit' exits.  Right now your
> > script will terminate immediately after the 'kill', and
> > that's going to cause GDM to try to proceed to do something
> > else with this server instance.
>
> Hi Mike,
>
> Wow, this seems to have taken a big step forward, although it's still
> not quite working.  After adding 'wait' at the end of the script, the
> behavior is a bit different.  It starts up the failsafe session like
> before, but now after a second or two it overlays the screen with a
> warning dialog.  Unfortunately, after clearing the dialog, it still goes
> back to restarting the x server.  But I think this means that now gdm is
> hearing back that the X process is running.
>
> The full log is here:
>    people.ubuntu.com/~bryce/files/gdm-syslog.log
>
> The interesting parts of the log:
>
> Aug 30 18:45:41 dorset gdm[7848]: DEBUG: gdm_server_spawn: '/etc/gdm/failsafeExample :0 -auth /var/lib/gdm/:0.Xauth -nolisten tcp vt9' 
> Aug 30 18:45:41 dorset gdm[7842]: DEBUG: gdm_server_spawn: Forked server on pid 7848 
> Aug 30 18:45:41 dorset gdm[7842]: DEBUG: do_server_wait: Before mainloop waiting for server 
> ...
> Aug 30 18:45:46 dorset gdm[7842]: DEBUG: gdm_server_start: After mainloop waiting for server 
> Aug 30 18:45:46 dorset gdm[7842]: DEBUG: gdm_server_start: Completed :0! 
> Aug 30 18:45:46 dorset gdm[7842]: DEBUG: Sending VT_NUM == 9 for slave 7842 
> ...
> Aug 30 18:45:46 dorset gdm[7786]: DEBUG: Handling message: 'VT_NUM 7842 9' 
> Aug 30 18:45:46 dorset gdm[7786]: DEBUG: Got VT_NUM == 9 
> Aug 30 18:45:46 dorset gdm[7842]: DEBUG: Sending XPID == 7848 for slave 7842 
> ...
> Aug 30 18:45:46 dorset gdm[7786]: DEBUG: Handling message: 'XPID 7842 7848' 
> Aug 30 18:45:46 dorset gdm[7786]: DEBUG: Got XPID == 7848 
> Aug 30 18:45:46 dorset gdm[7842]: DEBUG: gdm_slave_run: Opening display :0 
> ...
> Aug 30 18:45:46 dorset gdm[7786]: DEBUG: Handling message: 'START_NEXT_LOCAL' 
> ...
> Aug 30 18:45:46 dorset gdm[7842]: DEBUG: gdm_slave_greeter: Running greeter on :0 
> Aug 30 18:45:46 dorset gdm[7842]: DEBUG: Attempting to parse key string: daemon/DisplayInitDir=/etc/gdm/Init 
> Aug 30 18:45:46 dorset gdm[7842]: DEBUG: Forking extra process: /etc/gdm/Init/Default 
> ...
> Aug 30 18:45:46 dorset gdm[7842]: DEBUG: Forking greeter process: /usr/lib/gdm/gdmgreeter 
> ...
> Aug 30 18:45:46 dorset gdm[7862]: DEBUG: Sending SHOW_ERROR_DIALOG == <secret> for slave 7862 
> Aug 30 18:45:46 dorset gdm[7786]: DEBUG: Attempting to parse key string: debug/Enable=false 
> Aug 30 18:45:46 dorset gdm[7786]: DEBUG: Handling message: 'opcode=SHOW_ERROR_DIALOG$$pid=7842$$type=3$$error=Could not start the regular X server (your graphical environment) and so this is a failsafe X server.  You should log in and properly configure the X server.$$details_label=NIL$$details_file=NIL$$uid=0$$gid=0' 
> Aug 30 18:45:46 dorset gdm[7786]: DEBUG: Forking extra process: error dialog 
> ...
> Aug 30 18:45:46 dorset gdm[7863]: Gtk-WARNING: Ignoring the separator setting 
> Aug 30 18:45:46 dorset gdm[7842]: DEBUG: gdm_slave_greeter: Greeter on pid 7862 
> Aug 30 18:45:46 dorset gdm[7842]: DEBUG: Sending GREETPID == 7862 for slave 7842 
>
>
> I'm curious what this 'START_NEXT_LOCAL' bit is?

The slave sends this to the main daemon when it has finished starting up a local
display.  The daemon starts them one-at-a-time to avoid problems trying to start
them all at once, I think.

> I take it the greeter is what creates this SHOW_ERROR_DIALOG stuff?  Is
> there a way to turn that off?  (I display my own greet dialog as part of
> the failsafe code).

No, there isn't an easy way to tell GDM not to start up the greeter.  This
would, I think, require hacking the code to do what you want.

Brian