Bug 208631

Summary: Plasma crash when dragging the taskmanager around the panel [AppletIconWidget::mouseMoveEvent, QGraphicsItem::sceneEvent, QGraphicsWidget::sceneEvent]
Product: [Unmaintained] plasma4 Reporter: Dario Massarin <nekkar>
Component: widget explorerAssignee: Plasma Bugs List <plasma-bugs>
Status: RESOLVED WORKSFORME    
Severity: crash CC: alex.merry, anaceciliamb, andresbajotierra, asraniel, Jmlevick
Priority: NOR    
Version: unspecified   
Target Milestone: ---   
Platform: Compiled Sources   
OS: Linux   
Latest Commit: Version Fixed In:
Sentry Crash Report:
Attachments: New crash information added by DrKonqi

Description Dario Massarin 2009-09-26 20:18:31 UTC
Application: plasma-desktop (0.3)
KDE Version: 4.3.69 (KDE 4.3.69 (KDE 4.4 >= 20090923)) (Compiled from sources)
Qt Version: 4.5.1
Operating System: Linux 2.6.29-gentoo-r5 i686

What I was doing when the application crashed:
Was just playing around with the new "AddWidget" interface, and was trying to drag the taskmanager widget on the panel. The dragging operation seemed to get in trouble, since you couldn't see the paste area highlighted on the panel, (like it is used to do, when you drag a widget over it). Then I got this crash 

 -- Backtrace:
Application: Plasma Workspace (kdeinit4), signal: Segmentation fault
[Current thread is 0 (LWP 28393)]

Thread 2 (Thread 0xa840bb90 (LWP 28396)):
#0  0xb7f8b424 in __kernel_vsyscall ()
#1  0xb7d4dbf5 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#2  0xb7dd60e4 in QWaitConditionPrivate::wait (this=0x993e740, time=4294967295) at thread/qwaitcondition_unix.cpp:87
#3  0xb7dd5be3 in QWaitCondition::wait (this=0x99f1538, mutex=0x99f1534, time=4294967295) at thread/qwaitcondition_unix.cpp:159
#4  0xb76cbddb in QHostInfoAgent::run (this=0x99f1528) at kernel/qhostinfo.cpp:260
#5  0xb7dd57bf in QThreadPrivate::start (arg=0x99f1528) at thread/qthread_unix.cpp:189
#6  0xb7d4a16f in start_thread () from /lib/libpthread.so.0
#7  0xb66bddce in clone () from /lib/libc.so.6

Thread 1 (Thread 0xb5fc4700 (LWP 28393)):
[KCrash Handler]
#5  0x09f28ab8 in ?? ()
#6  0xb39fe53b in AppletIconWidget::mouseMoveEvent (this=0x9f5bed0, event=0xbf8a2700) at /opt/kde/kdebase/workspace/libs/plasmagenericshell/widgetsExplorer/appleticon.cpp:92
#7  0xb7033114 in QGraphicsItem::sceneEvent (this=0x9f5bed8, event=0xbf8a2700) at graphicsview/qgraphicsitem.cpp:5010
#8  0xb706f3e9 in QGraphicsWidget::sceneEvent (this=0x9f5bed0, event=0xbf8a2700) at graphicsview/qgraphicswidget.cpp:1110
#9  0xb703e732 in QGraphicsScenePrivate::sendEvent (this=0x972c208, item=0x9f5bed8, event=0xbf8a2700) at graphicsview/qgraphicsscene.cpp:1159
#10 0xb7044bee in QGraphicsScenePrivate::sendMouseEvent (this=0x972c208, mouseEvent=0xbf8a2700) at graphicsview/qgraphicsscene.cpp:1230
#11 0xb7050bc3 in QGraphicsScene::mouseMoveEvent (this=0x96a3448, mouseEvent=0xbf8a2700) at graphicsview/qgraphicsscene.cpp:4424
#12 0xb704e515 in QGraphicsScene::event (this=0x96a3448, event=0xbf8a2700) at graphicsview/qgraphicsscene.cpp:3807
#13 0xb69bc24d in QApplicationPrivate::notify_helper (this=0x9645af8, receiver=0x96a3448, e=0xbf8a2700) at kernel/qapplication.cpp:4057
#14 0xb69bc601 in QApplication::notify (this=0x9638e98, receiver=0x96a3448, e=0xbf8a2700) at kernel/qapplication.cpp:3604
#15 0xb74343f1 in KApplication::notify (this=0x9638e98, receiver=0x96a3448, event=0xbf8a2700) at /opt/kde/kdelibs/kdeui/kernel/kapplication.cpp:302
#16 0xb7eca683 in QCoreApplication::notifyInternal (this=0x9638e98, receiver=0x96a3448, event=0xbf8a2700) at kernel/qcoreapplication.cpp:606
#17 0xb7ece211 in QCoreApplication::sendEvent (receiver=0x96a3448, event=0xbf8a2700) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:213
#18 0xb706440b in QGraphicsViewPrivate::mouseMoveEventHandler (this=0xa062058, event=0xbf8a3004) at graphicsview/qgraphicsview.cpp:605
#19 0xb70651a6 in QGraphicsView::mouseMoveEvent (this=0x9ddb2b8, event=0xbf8a3004) at graphicsview/qgraphicsview.cpp:3299
#20 0xb6a1d262 in QWidget::event (this=0x9ddb2b8, event=0xbf8a3004) at kernel/qwidget.cpp:7506
#21 0xb6e2fb30 in QFrame::event (this=0x9ddb2b8, e=0xbf8a3004) at widgets/qframe.cpp:559
#22 0xb6ecd85b in QAbstractScrollArea::viewportEvent (this=0x9ddb2b8, e=0xbf8a3004) at widgets/qabstractscrollarea.cpp:962
#23 0xb705e423 in QGraphicsView::viewportEvent (this=0x9ddb2b8, event=0xbf8a3004) at graphicsview/qgraphicsview.cpp:2897
#24 0xb6ed044a in QAbstractScrollAreaPrivate::viewportEvent (this=0xa062058, event=0xbf8a3004) at widgets/qabstractscrollarea_p.h:100
#25 0xb6ed0478 in QAbstractScrollAreaFilter::eventFilter (this=0x9f01938, o=0xa029468, e=0xbf8a3004) at widgets/qabstractscrollarea_p.h:111
#26 0xb7ec8a48 in QCoreApplicationPrivate::sendThroughObjectEventFilters (this=0x9645af8, receiver=0xa029468, event=0xbf8a3004) at kernel/qcoreapplication.cpp:726
#27 0xb69bc22a in QApplicationPrivate::notify_helper (this=0x9645af8, receiver=0xa029468, e=0xbf8a3004) at kernel/qapplication.cpp:4053
#28 0xb69bcfd0 in QApplication::notify (this=0x9638e98, receiver=0xa029468, e=0xbf8a3004) at kernel/qapplication.cpp:3759
#29 0xb74343f1 in KApplication::notify (this=0x9638e98, receiver=0xa029468, event=0xbf8a3004) at /opt/kde/kdelibs/kdeui/kernel/kapplication.cpp:302
#30 0xb7eca683 in QCoreApplication::notifyInternal (this=0x9638e98, receiver=0xa029468, event=0xbf8a3004) at kernel/qcoreapplication.cpp:606
#31 0xb69c7f27 in QCoreApplication::sendSpontaneousEvent (receiver=0xa029468, event=0xbf8a3004) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:216
#32 0xb69c0fba in QApplicationPrivate::sendMouseEvent (receiver=0xa029468, event=0xbf8a3004, alienWidget=0xa029468, nativeWidget=0xa0910e8, buttonDown=0xb71a9da0, lastMouseReceiver=@0xb71a9da4)
    at kernel/qapplication.cpp:2925
#33 0xb6a3e5ae in QETWidget::translateMouseEvent (this=0xa0910e8, event=0xbf8a45c0) at kernel/qapplication_x11.cpp:4448
#34 0xb6a3f6cf in QApplication::x11ProcessEvent (this=0x9638e98, event=0xbf8a45c0) at kernel/qapplication_x11.cpp:3444
#35 0xb6a6a711 in x11EventSourceDispatch (s=0x96483a0, callback=0, user_data=0x0) at kernel/qguieventdispatcher_glib.cpp:146
#36 0xb65305a1 in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#37 0xb6533aeb in ?? () from /usr/lib/libglib-2.0.so.0
#38 0x09647c20 in ?? ()
#39 0x00000000 in ?? ()

Reported using DrKonqi
Comment 1 Alex Merry 2010-02-12 15:28:36 UTC
Created attachment 40715 [details]
New crash information added by DrKonqi

I managed to trigger what looks like the same problem by removing Kickoff (using the context menu) then trying to drag Lancelot to the left of the panel (using the add widgets interface from the toolbar configuration).

The drag operation got stuck, with the Lancelot icon displayed part-way to where I dragged it, and the mouse showing an "invalid drop location" cursor.  Plasma seemed to freeze completely for about a minute, then crashed when I activated KRunner using the keyboard shortcut.

There's nothing special about my plasma configuration - it's pretty much the default, except that I added a battery indicator to the panel, and changed the desktop picture.
Comment 2 Dario Andres 2010-03-21 01:04:48 UTC
Updated backtrace from last comment:
---
#5  0x00007f5a3b5923ca in AppletIconWidget::mouseMoveEvent (this=0x31db330, event=0x7fff2b715a90)
    at /home/kde-devel/src/KDE/kdebase/workspace/libs/plasmagenericshell/widgetsexplorer/appleticon.cpp:101
#6  0x00007f5a4769dfa1 in QGraphicsItem::sceneEvent (this=0x31db340, event=0x7fff2b715a90) at /home/kde-devel/src/qt/src/gui/graphicsview/qgraphicsitem.cpp:6395
#7  0x00007f5a477036fb in QGraphicsWidget::sceneEvent (this=0x31db330, event=0x7fff2b715a90) at /home/kde-devel/src/qt/src/gui/graphicsview/qgraphicswidget.cpp:1129
Comment 3 Dario Andres 2010-03-21 01:05:21 UTC
From bug 230926:
VirtualBox was running, trying to start Fedora 13 Alpha; at the same time I
wanted to add an element to the bottom panel (an Application Launcher widget).
The minimized VirtualBox window maximized itself in a weird way and the whole
desktop dissapeared
Comment 4 Dario Andres 2010-03-21 01:05:26 UTC
*** Bug 230926 has been marked as a duplicate of this bug. ***
Comment 5 Beat Wolf 2010-06-08 23:03:06 UTC
could not reproduce in trunk. please reopen if you can.