Bug 139080 – Right-click Close during Heavy System Load: Crashes WNCK (2.6.0)

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Bug 139080 - Right-click Close during Heavy System Load: Crashes WNCK (2.6.0)


Summary:	Right-click Close during Heavy System Load: Crashes WNCK (2.6.0)


Status:	RESOLVED FIXED

Product:	libwnck
Classification:	Core
Component:	tasklist
Version:	unspecified
Hardware:	Other Linux

Importance:	High critical
Target Milestone:	---
Assigned To:	libwnck maintainers
QA Contact:	libwnck maintainers

URL:
Whiteboard:

Depends on:
Blocks:

Reported:	2004-04-04 23:45 UTC by Matt T. Proud
Modified:	2007-07-31 03:02 UTC

See Also:
GNOME target:	---
GNOME version:	---

Attachments
remove weak pointers before destroying objects (620 bytes, patch) 2007-07-30 18:08 UTC, Ray Strode [halfline]	committed	Details \| Review

Description Matt T. Proud 2004-04-04 23:45:42 UTC

I found today that while right-clicking on the items in the window list and
using the context-menu functions, mainly the "Close" function, that WNCK had a
propensity to crash.

Backtrace from one of the crashes:

Backtrace was generated from '/usr/libexec/wnck-applet'

Using host libthread_db library "/lib/libthread_db.so.1".
[Thread debugging using libthread_db enabled]
[New Thread 16384 (LWP 8103)]
0x40b3f018 in waitpid () from /lib/libpthread.so.0

+ Trace 45700

Thread 1 (Thread 16384 (LWP 8103))

#0 waitpid
from /lib/libpthread.so.0
#1 __JCR_LIST__
from /usr/lib/libgnomeui-2.so.0
#2 libgnomeui_segv_handle
at gnome-ui-init.c line 741
#3 __pthread_sighandler
at sighandler.c line 39
#4 <signal handler called>
#5 handlers_find
at gsignal.c line 508
#6 signal_handlers_foreach_matched_R
at gsignal.c line 1847
#7 g_signal_handlers_disconnect_matched
at gsignal.c line 1932
#8 gtk_tooltips_destroy_data
at gtktooltips.c line 140
#9 g_cclosure_marshal_VOID__VOID
at gmarshal.c line 77
#10 g_closure_invoke
at gclosure.c line 437
#11 signal_emit_unlocked_R
at gsignal.c line 2436
#12 g_signal_emit_valist
at gsignal.c line 2195
#13 g_signal_emit
at gsignal.c line 2239
#14 gtk_object_dispose
at gtkobject.c line 376
#15 gtk_widget_dispose
at gtkwidget.c line 6357
#16 g_object_run_dispose
at gobject.c line 602
#17 gtk_object_destroy
at gtkobject.c line 361
#18 gtk_widget_destroy
at gtkwidget.c line 1913
#19 wnck_task_finalize
at tasklist.c line 322
#20 g_object_last_unref
at gobject.c line 570
#21 wnck_tasklist_remove
at tasklist.c line 1210
#22 g_cclosure_marshal_VOID__OBJECT
at gmarshal.c line 636
#23 g_type_class_meta_marshal
at gclosure.c line 514
#24 g_closure_invoke
at gclosure.c line 437
#25 signal_emit_unlocked_R
at gsignal.c line 2366
#26 g_signal_emit_valist
at gsignal.c line 2195
#27 g_signal_emit
at gsignal.c line 2239
#28 gtk_container_remove
at gtkcontainer.c line 994
#29 gtk_widget_dispose
at gtkwidget.c line 6351
#30 g_object_run_dispose
at gobject.c line 602
#31 gtk_object_destroy
at gtkobject.c line 361
#32 gtk_widget_destroy
at gtkwidget.c line 1913
#33 wnck_tasklist_free_tasks
at tasklist.c line 1371
#34 wnck_tasklist_update_lists
at tasklist.c line 1435
#35 wnck_tasklist_window_removed
at tasklist.c line 1723
#36 g_cclosure_marshal_VOID__OBJECT
at gmarshal.c line 636
#37 g_closure_invoke
at gclosure.c line 437
#38 signal_emit_unlocked_R
at gsignal.c line 2436
#39 g_signal_emit_valist
at gsignal.c line 2195
#40 g_signal_emit
at gsignal.c line 2239
#41 emit_window_closed
at screen.c line 1554
#42 update_client_list
at screen.c line 1045
#43 do_update_now
at screen.c line 1472
#44 update_idle
at screen.c line 1493
#45 g_idle_dispatch
at gmain.c line 3750
#46 g_main_dispatch
at gmain.c line 1895
#47 g_main_context_dispatch
at gmain.c line 2441
#48 g_main_context_iterate
at gmain.c line 2522
#49 g_main_loop_run
at gmain.c line 2726
#50 bonobo_main
at bonobo-main.c line 297
#51 bonobo_generic_factory_main_timeout
at bonobo-generic-factory.c line 384
#52 bonobo_generic_factory_main
at bonobo-generic-factory.c line 341
#53 panel_applet_factory_main_closure
at panel-applet.c line 1556
#54 panel_applet_factory_main
at panel-applet.c line 1580
#55 main
at wncklet.c line 77
#0 waitpid
from /lib/libpthread.so.0

Comment 1 Kjartan Maraas 2004-04-18 19:19:58 UTC

What version of libwnck, gnome-panel, gtk+ etc did you use to get this? Also
telling us the exact steps to reproduce this would  be helpful.

Comment 2 Vincent Noel 2005-01-28 18:21:37 UTC

Moving to the right component. Sorry for the spam :p

Comment 3 André Klapper 2006-07-03 15:10:19 UTC

Closing this bug report as no further information has been provided. Please feel free to reopen this bug if you can provide the information asked for.
Thanks!

Comment 4 Ray Strode [halfline] 2007-07-30 18:03:18 UTC

We had a customer hit this bug here:

https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=192963

(although most of the comments are private unfortunately)

Comment 5 Ray Strode [halfline] 2007-07-30 18:08:46 UTC

Created attachment 92729 [details] [review]
remove weak pointers before destroying objects

So it turned out the problem was that the button and action_menu of a task were living slightly longer than the task itself (because the task was getting finalized as part of the destruction of the button), so the button/action_menu pointers were getting nullified after the task block was freed.

Comment 6 Elijah Newren 2007-07-31 02:46:17 UTC

Nothing beats someone else tracking down the cause and fixing it.  :-)

Thanks, Ray, I'll assume you and others have tested the patch (as you said, most the comments are private in that other bug report), so go ahead and commit.

Comment 7 Ray Strode [halfline] 2007-07-31 03:02:15 UTC

2007-07-30  Ray Strode  <rstrode@redhat.com>

        * libwnck/tasklist.c (wnck_task_finalize): remove weak
        pointers on fields in task structure before freeing task
        block (bug 139080)