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kiosk mode crash with xfce4-panel
Status:
RESOLVED: WORKSFORME
Product:
Xfce4-panel

Comments

Description Asalkhanov Peter 2004-10-09 20:49:13 CEST
I have xfce4 beta1 (4.1.90), gtk-engines-xfce 2.2.0, and am running a gentoo
system with 2.6.8 kernel.

After uninstalling the stable version (4.0.6), and installing the beta, I
encountered the following problem:
For some reason on one of the users, after xfce starts, panel does not load, nor
the menus are accessible.
Others work fine. My guess was that it is xfce4-session that was responsible, so
I commented it out in ~/.config/xfce4/xinitrc, and restarted xfce, and it now
gives a message: "A crash occured in the panel. Please report this to the
xfce4-dev@moongroup.com group. Meanwhile the panel will be restarted."

(Sidenote: xfcalendar did not load with xfce4-session, and now it does).

The message continues to cycle merrily in a vicious circle. Again, under any
other users it works fine. I tried deleting all the files that xfce4 creates,
and restart, but that does not help.

There is only one explanation that I can think of. During the compilation, I
logged in as that user once most of the packages were there.
On other hand uninstalling and recompilling did not help either.

Running xfce4-panel in a terminal just gives: Segmentation fault.
I am not sure how to get more debug information out of it without installing a
gdb (which I am not too keen on doing, but can do). Are there any debug flags,
that can be used?
Comment 1 Jasper Huijsmans editbugs 2004-10-10 07:26:45 CEST
I'm afraid you need a debugger (gdb) to get this information. What we need is a
backtrace.

In a terminal type:

 $ gdb xfce4-panel
gdb> run
 ... *crash*
gdb> bt
 <output>

Thanks,
Jasper
Comment 2 Asalkhanov Peter 2004-10-10 08:15:36 CEST
Created attachment 74 
The log of stuff that gdm generates.

Unfortunately, its kinda not all that informative, except for the reference of
xfce_kiosk_free() from /usr/lib/libxfce4util.so.1
If you need to see the stacks and the like, I'll do it after I get some sleep.
HTH.
Comment 3 Asalkhanov Peter 2004-10-10 08:20:52 CEST
Comment on attachment 74 
The log of stuff that gdm generates.


>Program received signal SIGSEGV, Segmentation fault.
>0x4008e7e6 in xfce_kiosk_free () from /usr/lib/libxfce4util.so.1
(gdb) bt
#0  0x4008e7e6 in xfce_kiosk_free () from /usr/lib/libxfce4util.so.1
#1  0x00000001 in ?? ()
#2  0x00000001 in ?? ()
(gdb) c
Continuing.

Program terminated with signal SIGSEGV, Segmentation fault.
The program no longer exists.
(gdb) quit


--
Err, sorry for missing the bt part. Im kind of sleepy after the night shift.
Here it is.
Comment 4 Jasper Huijsmans editbugs 2004-10-10 08:55:44 CEST
Thanks. Very strange it should crash here. I'll investigate.
Comment 5 Asalkhanov Peter 2004-10-10 15:33:41 CEST
Created attachment 75 
GDB of xfce4-session, no backtrace.

(In reply to comment #4)
> Thanks. Very strange it should crash here. I'll investigate.

I did run xfce4-session through the gdm to see what it does, and it seems to
indicate that the panel is the offender. session runs all well untill:
It times out on something. I bet it is the panel.
Comment 6 Jasper Huijsmans editbugs 2004-10-10 16:51:42 CEST
(In reply to comment #5)
> I bet it is the panel.

It is, sorry, I saw that already from the backtrace. Unfortunately, I don't see
how it can crash on that particular piece of code :/ Must be some sort of memory
corruption.

I never heard of this before, so I'm not sure where to start looking. If you
find out more, please let me know. This bug will be hard to find, I fear.

Comment 7 Asalkhanov Peter 2004-10-10 19:25:36 CEST
Ok, I managed to work around this bug. I backed up my home directory, deleted
user (along with /home and all stuff in /var related to that user account). I
recreated the user with the same uid, and will now start poking to see what
causes the breakage.
I'll post any updates I find out. It seems to be a very esoteric bug. 
Comment 8 Asalkhanov Peter 2004-10-10 19:44:44 CEST
And now I know what causes it. At least how to make it reproducable.
It is related to user belonging to some specific group (I have a vague idea what
it might be, but not exact group). I've managed to both make the panel work
(i.e. by deleting/adding my user, and then by trying restore it to what it was
during the crashes). For some reason, that particular user belonged to all
existing groups. And belonging to one of them, makes the panel crash.

It is supposed to be reproducable. Neither KDE nor Xfce 4.0.6 had problem with
that too.
Comment 9 Jasper Huijsmans editbugs 2004-10-10 20:08:23 CEST
(In reply to comment #8)
> And now I know what causes it. At least how to make it reproducable.
> It is related to user belonging to some specific group (I have a vague idea what
> it might be, but not exact group). I've managed to both make the panel work
> (i.e. by deleting/adding my user, and then by trying restore it to what it was
> during the crashes). For some reason, that particular user belonged to all
> existing groups. And belonging to one of them, makes the panel crash.
> 
> It is supposed to be reproducable. Neither KDE nor Xfce 4.0.6 had problem with
> that too.

That's very helpful, thanks. It's definitely an Xfce bug, in the new kiosk mode
support to be precise. That should make it much easier to find.
Comment 10 Jasper Huijsmans editbugs 2004-11-06 09:07:19 CET
(In reply to comment #9)
> 
> That's very helpful, thanks. It's definitely an Xfce bug, in the new kiosk mode
> support to be precise. That should make it much easier to find.

Guess I was a bit too soon. It's still unclear how that bug could happen. We've
made a few changes, so hopefully the next pre-release (RC1) will no have this
problem.
Comment 11 Jasper Huijsmans editbugs 2004-11-14 10:18:45 CET
Please reopen if it still happens with RC1.

Bug #382

Reported by:
Asalkhanov Peter
Reported on: 2004-10-09
Last modified on: 2010-11-20

People

Assignee:
Nick Schermer
CC List:
1 user

Version

Attachments

The log of stuff that gdm generates. (1.76 KB, text/plain)
2004-10-10 08:15 CEST , Asalkhanov Peter
no flags
GDB of xfce4-session, no backtrace. (36.41 KB, text/plain)
2004-10-10 15:33 CEST , Asalkhanov Peter
no flags

Additional information