unity-panel-service crashed with SIGSEGV in g_object_unref()

[Angel Guzman Maeso]

This crash makes unusable the desktop. Tho unity-panels appears, one on left (primary screen) and two on second screen (left and right)

ProblemType: Crash
DistroRelease: Ubuntu 12.10
Package: unity-services 5.12-0ubuntu4
ProcVersionSignature: Ubuntu 3.5.0-3.3-generic 3.5.0-rc5
Uname: Linux 3.5.0-3-generic i686
ApportVersion: 2.3-0ubuntu2
Architecture: i386
Date: Wed Jul 11 00:10:19 2012
ExecutablePath: /usr/lib/unity/unity-panel-service
InstallationMedia:

ProcCmdline: /usr/lib/unity/unity-panel-service
ProcEnviron:
 SHELL=/bin/bash
 PATH=(custom, no user)
 LANG=es_ES.UTF-8
SegvAnalysis:
 Segfault happened at: 0xb7010386 <g_object_unref+38>: mov (%esi),%eax
 PC (0xb7010386) ok
 source "(%esi)" (0xaaaaaaaa) not located in a known VMA region (needed readable region)!
 destination "%eax" ok
SegvReason: reading unknown VMA
Signal: 11
SourcePackage: unity
StacktraceTop:
 g_object_unref (_object=0xaaaaaaaa) at /build/buildd/glib2.0-2.33.3/./gobject/gobject.c:2915
 ?? () from /usr/lib/indicators3/7/libappmenu.so
 g_object_unref (_object=0x8a6e000) at /build/buildd/glib2.0-2.33.3/./gobject/gobject.c:2986
 ?? ()
 ?? ()
Title: unity-panel-service crashed with SIGSEGV in g_object_unref()
UpgradeStatus: Upgraded to quantal on 2012-06-05 (35 days ago)
UserGroups: adm admin audio cdrom dialout dip fax floppy fuse lpadmin netdev plugdev sambashare tape vboxusers video

[Apport retracing service (apport)]

StacktraceTop:
 g_object_unref (_object=0xaaaaaaaa) at /build/buildd/glib2.0-2.33.3/./gobject/gobject.c:2915
 menus_destroyed (user_data=<optimized out>, menus=0x8a6e008) at indicator-appmenu.c:1147
 unregister_window (iapp=<optimized out>, windowid=<optimized out>) at indicator-appmenu.c:1251
 ?? () from /tmp/tmpItYjS7/usr/lib/i386-linux-gnu/libgobject-2.0.so.0

[Sebastien Bacher (seb128)]

Thank you for your bug report, did that start recently? What version of indicator-appmenu do you have installed? When does it happen?

[Angel Guzman Maeso (shakaran)]

This happens some hours ago. I have indicator-appmenu 12.10.0-0ubuntu1

The behaviour is how like two instances are spawned. It could be caused, because it crash, then I pres Alt+F1, write unity --reset on terminal, and switch back with Alt+F7. I did this often when unity crash (also my desktop get very slow running 2 o 3 days, even on unity-2d). So probably, another unity intance spawn on some moment and I get two instances. This could be a corner case. If happens again, I will make a screenshot or camera shot.

[Bilal Akhtar (bilalakhtar)]

The stacktrace seems like something went wrong when a window was closed. So it could happen in other cases too.

[Charles Kerr (charlesk)]

A pointer of 0xaaaaaaaa is pretty suspicious... :)

Thread 1 (Thread 0xb6669840 (LWP 22026)):
#0 0xb7010386 in g_object_unref (_object=0xaaaaaaaa) at /build/buildd/glib2.0-2.33.3/./gobject/gobject.c:2915
        __inst = 0xaaaaaaaa
        __r = <optimized out>
        _g_boolean_var_ = <optimized out>
        object = 0xaaaaaaaa
        old_ref = <optimized out>
        __PRETTY_FUNCTION__ = "g_object_unref"
#1 0xae465ae4 in menus_destroyed (user_data=<optimized out>, menus=0x8a6e008) at indicator-appmenu.c:1147
        reload_menus = 0
        wm = 0xb70104c8
        iapp = 0x8a6e000
        xid = 2863311530
#2 unregister_window (iapp=<optimized out>, windowid=<optimized out>) at indicator-appmenu.c:1251
        wmo = 0x8a6e008
        __PRETTY_FUNCTION__ = "unregister_window"
        wm = <optimized out>

[Charles Kerr (charlesk)]

Angel, could you test and see if this crash is still happening for you in 12.10 beta 2?

[Angel Guzman Maeso (shakaran)]

Fully updated quantal today (beta 2). This is still fully reproducible. I attach a screenshot with the two panels. This is a phisical install (64 bits), no virtualized in VM.