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xfdesktop crashed with SIGSEGV in XScreenCount()
Status:
RESOLVED: WORKSFORME
Product:
Xfdesktop
Component:
General

Comments

Description Thaddaeus Tintenfisch editbugs 2014-08-31 14:00:51 CEST
[forwarded from launchpad]

After upgrade from XUbuntu 12.04 to 14.04.1 I started to get frequent xfdesktop crashes.

Crash stack trace in apport is confusing for me so I can't say what caused it. It happends randomly, sometimes right after reboot. How to reproduce? I just have to wait.

----
I tried to run it from console, and this is all I get in console:
sudo xfdesktop --display=:0.0 --reload

Failed to connect to session manager: Could not connect to session manager: SESSION_MANAGER environment variable not defined

----
xfdesktop --version

This is xfdesktop version 4.11.6, running on Xfce 4.10.
Built with GTK+ 2.24.23, linked with GTK+ 2.24.23.
Build options:
    Desktop Menu: enabled
    Desktop Icons: enabled
    Desktop File Icons: enabled
----
lsb_release -rd
Description: Ubuntu 14.04.1 LTS
Release: 14.04

https://bugs.launchpad.net/ubuntu/+source/xfdesktop4/+bug/1358482/+attachment/4181091/+files/_usr_bin_xfdesktop.1000.crash.tar.gz
Comment 1 Eric Koegel editbugs 2014-09-01 09:23:30 CEST
First, there's no need to run xfdesktop with sudo. You'll get the session warning because you aren't logged in as root so there's no session running for it.

From the stack trace it, the only xfdesktop call in that stack is xfdesktop_application_run (), which is located here:
http://git.xfce.org/xfce/xfdesktop/tree/src/xfdesktop-application.c#n773
It's really hard for me to get that wrong! :)

Is there anyway you can do a stack trace with the debug symbols installed? Maybe that will provide more detail to this bug.
http://docs.xfce.org/contribute/bugs/start#backtraces May be of some help setting your system up for it.


There's quite a few warning messages but luckily most of them have nothing to do with xfdesktop (seems to be vlc and libindicator don't get along well).

GLib-GObject-CRITICAL **: g_value_get_uint: assertion `G_VALUE_HOLDS_UINT (value)' failed
is interesting, maybe try running:
xfdesktop --quit; xfdesktop --g-fatal-warnings
If that warning message comes up then xfdesktop will crash, the backtrace from that may help pinpoint why that happens, but note that it probably won't help resolve this crash.
Comment 2 Eric Koegel editbugs 2014-09-01 09:26:34 CEST
SegvAnalysis:
 Segfault happened at: 0xb75a4724 <XScreenCount+4>:	mov    0x88(%eax),%eax
 PC (0xb75a4724) ok
 source "0x88(%eax)" (0x00000088) not located in a known VMA region (needed readable region)!
 destination "%eax" ok
SegvReason: reading NULL VMA
SourcePackage: xfdesktop4
Stacktrace:
 #0  0xb75a4724 in XScreenCount () from /usr/lib/i386-linux-gnu/libX11.so.6
 No symbol table info available.
 #1  0xb77216da in ?? ()
 No symbol table info available.
 #2  0xb6b9f709 in g_cclosure_marshal_VOID__VOIDv () from /usr/lib/i386-linux-gnu/libgobject-2.0.so.0
 No symbol table info available.
 #3  0xb6b9c457 in ?? () from /usr/lib/i386-linux-gnu/libgobject-2.0.so.0
 No symbol table info available.
 #4  0xb6b9dcce in ?? () from /usr/lib/i386-linux-gnu/libgobject-2.0.so.0
 No symbol table info available.
 #5  0xb6bb7080 in g_signal_emit_valist () from /usr/lib/i386-linux-gnu/libgobject-2.0.so.0
 No symbol table info available.
 #6  0xb6bb7bf3 in g_signal_emit () from /usr/lib/i386-linux-gnu/libgobject-2.0.so.0
 No symbol table info available.
 #7  0xb6e984da in g_application_register () from /usr/lib/i386-linux-gnu/libgio-2.0.so.0
 No symbol table info available.
 #8  0xb7721212 in ?? ()
 No symbol table info available.
 #9  0xb6e9903d in g_application_run () from /usr/lib/i386-linux-gnu/libgio-2.0.so.0
 No symbol table info available.
 #10 0xb7721a3c in xfdesktop_application_run ()
 No symbol table info available.
 #11 0xb7714e7b in main ()
 No symbol table info available.

Xsession errors:
 (xfdesktop:3635): GLib-GObject-CRITICAL **: g_value_get_uint: assertion `G_VALUE_HOLDS_UINT (value)' failed
 (xfdesktop:3635): GLib-GObject-CRITICAL **: g_value_get_uint: assertion `G_VALUE_HOLDS_UINT (value)' failed
 (xfdesktop:3635): GLib-GObject-CRITICAL **: g_value_get_uint: assertion `G_VALUE_HOLDS_UINT (value)' failed
 (xfdesktop:3635): GLib-GObject-CRITICAL **: g_value_get_uint: assertion `G_VALUE_HOLDS_UINT (value)' failed

Saves me from having to grab the tar file again.
Comment 3 MiroJanosik 2014-10-06 23:24:01 CEST

I'm trying to reproduce crash while running it in GDB but I can't get it. When I run it from GDB it won't crash. Usually it crashes 3-times per day, now it is running in GDB for 3 days. This is my GDB output so far. What can I do next?

miro@uhlie:~$ xfdesktop --quit
miro@uhlie:~$ gdb
GNU gdb (Ubuntu 7.7-0ubuntu3.1) 7.7
Copyright (C) 2014 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
(gdb) exec-file xfdesktop
(gdb) run
Starting program: /usr/bin/xfdesktop xfdesktop
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/i386-linux-gnu/libthread_db.so.1".
[New Thread 0xb69d3b40 (LWP 23133)]
[New Thread 0xb5fffb40 (LWP 23134)]
[New Thread 0xb55ffb40 (LWP 23141)]
[New Thread 0xb4dfeb40 (LWP 23142)]

(xfdesktop:23129): GLib-GObject-CRITICAL **: g_value_get_uint: assertion 'G_VALUE_HOLDS_UINT (value)' failed
(xfdesktop:23129): GLib-GObject-CRITICAL **: g_value_get_uint: assertion 'G_VALUE_HOLDS_UINT (value)' failed
(xfdesktop:23129): GLib-GObject-CRITICAL **: g_value_get_uint: assertion 'G_VALUE_HOLDS_UINT (value)' failed
[Thread 0xb4dfeb40 (LWP 23142) exited]

(xfdesktop:23129): GLib-CRITICAL **: g_variant_new_string: assertion 'string != NULL' failed
[New Thread 0xb4dfeb40 (LWP 23213)]

(xfdesktop:23129): GLib-CRITICAL **: g_variant_new_string: assertion 'string != NULL' failed
[Thread 0xb4dfeb40 (LWP 23213) exited]

(xfdesktop-settings:23225): GLib-GObject-CRITICAL **: g_value_get_uint: assertion 'G_VALUE_HOLDS_UINT (value)' failed
(xfdesktop-settings:23225): GLib-GObject-CRITICAL **: g_value_get_uint: assertion 'G_VALUE_HOLDS_UINT (value)' failed
(xfdesktop-settings:23225): GLib-GObject-CRITICAL **: g_value_get_uint: assertion 'G_VALUE_HOLDS_UINT (value)' failed
(xfdesktop-settings:23244): GLib-GObject-CRITICAL **: g_value_get_uint: assertion 'G_VALUE_HOLDS_UINT (value)' failed
(xfdesktop-settings:23244): GLib-GObject-CRITICAL **: g_value_get_uint: assertion 'G_VALUE_HOLDS_UINT (value)' failed
(xfdesktop-settings:23244): GLib-GObject-CRITICAL **: g_value_get_uint: assertion 'G_VALUE_HOLDS_UINT (value)' failed

(xfdesktop:23129): GLib-CRITICAL **: g_variant_new_string: assertion 'string != NULL' failed
(xfdesktop:23129): GLib-CRITICAL **: g_variant_new_string: assertion 'string != NULL' failed
(xfdesktop:23129): GLib-CRITICAL **: g_variant_new_string: assertion 'string != NULL' failed
(xfdesktop:23129): GLib-CRITICAL **: g_variant_new_string: assertion 'string != NULL' failed

What can I do next?
Comment 4 MiroJanosik 2014-10-06 23:24:11 CEST
Hm no, xfdesktop now crashed, and I saw nothing interesting in the GDB, how come that, what am I doing wrong?
in ps afx I still see that only instance of xfdesktop is running under gdb.
Comment 5 Skunnyk editbugs 2017-06-21 23:24:08 CEST
Is it still crashing with 4.12.x ? 4.13.x (gtk-3) ?
Comment 6 Andre Miranda editbugs 2018-10-19 03:28:01 CEST
Closing, reopen if still an issue.

Bug #11123

Reported by:
Thaddaeus Tintenfisch
Reported on: 2014-08-31
Last modified on: 2018-10-19

People

Assignee:
Eric Koegel
CC List:
4 users

Version

Version:
Unspecified

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