Bug 318186

Summary:	Crash while dragging a window item from the panel via the desktop to the pager
Product:	[Plasma] kwin	Reporter:	Tilman Vogel <tilman.vogel>
Component:	general	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED UPSTREAM
Severity:	crash
Priority:	NOR
Version First Reported In:	unspecified
Target Milestone:	---
Platform:	openSUSE
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:
Attachments:	Screenshot "window buttons"

Description Tilman Vogel 2013-04-11 10:35:16 UTC

Application: kwin (4.10.00 "release 1")
KDE Platform Version: 4.10.00 "release 1"
Qt Version: 4.8.4
Operating System: Linux 3.7.10-1.1-desktop x86_64
Distribution: "openSUSE 12.3 (x86_64)"

-- Information about the crash:
- What I was doing when the application crashed:
I dragged a window item from the "task list" in the panel, moved the mouse out of the panel into the desktop area and then back to the pager in the panel.

-- Backtrace:
Application: KWin (kwin), signal: Segmentation fault
Using host libthread_db library "/lib64/libthread_db.so.1".
[Current thread is 1 (Thread 0x7fc04e7bd7c0 (LWP 3073))]

Thread 2 (Thread 0x7fc022a54700 (LWP 3086)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
#1  0x00007fc04a8a0307 in QTWTF::TCMalloc_PageHeap::scavengerThread (this=0x7fc04abad660 <QTWTF::pageheap_memory>) at ../3rdparty/javascriptcore/JavaScriptCore/wtf/FastMalloc.cpp:2359
#2  0x00007fc04a8a0339 in QTWTF::TCMalloc_PageHeap::runScavengerThread (context=<optimized out>) at ../3rdparty/javascriptcore/JavaScriptCore/wtf/FastMalloc.cpp:1464
#3  0x00007fc048f59e0f in start_thread (arg=0x7fc022a54700) at pthread_create.c:308
#4  0x00007fc04dfe77dd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:113

Thread 1 (Thread 0x7fc04e7bd7c0 (LWP 3073)):
[KCrash Handler]
#6  0x00007fc0492ebceb in QCoreApplicationPrivate::sendThroughApplicationEventFilters (this=0x1d4adc0, receiver=0x399e0b0, event=0x7fffb57bed60) at kernel/qcoreapplication.cpp:1027
#7  0x00007fc0484797e6 in QApplicationPrivate::notify_helper (this=this@entry=0x1d4adc0, receiver=receiver@entry=0x399e0b0, e=e@entry=0x7fffb57bed60) at kernel/qapplication.cpp:4537
#8  0x00007fc04847e693 in QApplication::notify (this=<optimized out>, receiver=0x2979bd0, e=0x7fffb57bed60) at kernel/qapplication.cpp:4348
#9  0x00007fc04dadfcb6 in KApplication::notify (this=0x7fffb57c3310, receiver=0x2979bd0, event=0x7fffb57bed60) at /usr/src/debug/kdelibs-4.10.0/kdeui/kernel/kapplication.cpp:311
#10 0x00007fc0492ebc9e in QCoreApplication::notifyInternal (this=0x7fffb57c3310, receiver=0x2979bd0, event=0x7fffb57bed60) at kernel/qcoreapplication.cpp:946
#11 0x00007fc048500ac7 in sendEvent (event=0x7fffb57bed60, receiver=0x2979bd0) at ../../src/corelib/kernel/qcoreapplication.h:231
#12 handle_xdnd_position (w=0x2979bd0, xe=0x7fffb57bf450, passive=false) at kernel/qdnd_x11.cpp:934
#13 0x00007fc0484f5970 in QApplication::x11ClientMessage (this=<optimized out>, w=0x2979bd0, event=<optimized out>, passive_only=<optimized out>) at kernel/qapplication_x11.cpp:3209
#14 0x00007fc0484f4172 in QApplication::x11ProcessEvent (this=0x7fffb57c3310, event=0x7fffb57bf450) at kernel/qapplication_x11.cpp:3789
#15 0x00007fc04851a9d9 in QEventDispatcherX11::processEvents (this=0x1d4ad50, flags=...) at kernel/qeventdispatcher_x11.cpp:132
#16 0x00007fc0492ea9ef in QEventLoop::processEvents (this=this@entry=0x3f0baf0, flags=...) at kernel/qeventloop.cpp:149
#17 0x00007fc0492eac78 in QEventLoop::exec (this=0x3f0baf0, flags=...) at kernel/qeventloop.cpp:204
#18 0x00007fc048501d26 in QDragManager::drag (this=0x2f3cb60, o=<optimized out>) at kernel/qdnd_x11.cpp:2028
#19 0x00007fc04848ace8 in QDrag::exec (this=0x3200d10, supportedActions=..., defaultDropAction=defaultDropAction@entry=Qt::IgnoreAction) at kernel/qdrag.cpp:284
#20 0x00007fc04848ada3 in QDrag::exec (this=<optimized out>, supportedActions=...) at kernel/qdrag.cpp:239
#21 0x00007fc031b9adf8 in ?? () from /usr/lib64/kde4/kwin3_oxygen.so
#22 0x00007fc031b940b4 in ?? () from /usr/lib64/kde4/kwin3_oxygen.so
#23 0x00007fc0492ebe06 in QCoreApplicationPrivate::sendThroughObjectEventFilters (this=<optimized out>, receiver=0x399e0b0, event=0x7fffb57bfff0) at kernel/qcoreapplication.cpp:1056
#24 0x00007fc04847983c in QApplicationPrivate::notify_helper (this=this@entry=0x1d4adc0, receiver=receiver@entry=0x399e0b0, e=e@entry=0x7fffb57bfff0) at kernel/qapplication.cpp:4558
#25 0x00007fc04847e54b in QApplication::notify (this=<optimized out>, receiver=0x399e0b0, e=0x7fffb57bfff0) at kernel/qapplication.cpp:4105
#26 0x00007fc04dadfcb6 in KApplication::notify (this=0x7fffb57c3310, receiver=0x399e0b0, event=0x7fffb57bfff0) at /usr/src/debug/kdelibs-4.10.0/kdeui/kernel/kapplication.cpp:311
#27 0x00007fc0492ebc9e in QCoreApplication::notifyInternal (this=0x7fffb57c3310, receiver=0x399e0b0, event=0x7fffb57bfff0) at kernel/qcoreapplication.cpp:946
#28 0x00007fc04847a6ab in sendEvent (event=<optimized out>, receiver=<optimized out>) at ../../src/corelib/kernel/qcoreapplication.h:231
#29 QApplicationPrivate::sendMouseEvent (receiver=0x399e0b0, event=0x7fffb57bfff0, alienWidget=0x0, nativeWidget=0x399e0b0, buttonDown=0x7fc048f4e268 <qt_button_down>, lastMouseReceiver=..., spontaneous=true) at kernel/qapplication.cpp:3173
#30 0x00007fc0484f4e94 in QETWidget::translateMouseEvent (this=this@entry=0x399e0b0, event=event@entry=0x7fffb57c0770) at kernel/qapplication_x11.cpp:4527
#31 0x00007fc0484f3c21 in QApplication::x11ProcessEvent (this=0x7fffb57c3310, event=0x7fffb57c0770) at kernel/qapplication_x11.cpp:3650
#32 0x00007fc04851a9d9 in QEventDispatcherX11::processEvents (this=0x1d4ad50, flags=...) at kernel/qeventdispatcher_x11.cpp:132
#33 0x00007fc0492ea9ef in QEventLoop::processEvents (this=this@entry=0x3039e40, flags=...) at kernel/qeventloop.cpp:149
#34 0x00007fc0492eac78 in QEventLoop::exec (this=0x3039e40, flags=...) at kernel/qeventloop.cpp:204
#35 0x00007fc048501d26 in QDragManager::drag (this=0x2f3cb60, o=<optimized out>) at kernel/qdnd_x11.cpp:2028
#36 0x00007fc04848ace8 in QDrag::exec (this=0x3839620, supportedActions=..., defaultDropAction=defaultDropAction@entry=Qt::IgnoreAction) at kernel/qdrag.cpp:284
#37 0x00007fc04848ada3 in QDrag::exec (this=<optimized out>, supportedActions=...) at kernel/qdrag.cpp:239
#38 0x00007fc031b9adf8 in ?? () from /usr/lib64/kde4/kwin3_oxygen.so
#39 0x00007fc031b940b4 in ?? () from /usr/lib64/kde4/kwin3_oxygen.so
#40 0x00007fc0492ebe06 in QCoreApplicationPrivate::sendThroughObjectEventFilters (this=<optimized out>, receiver=0x295e9d0, event=0x7fffb57c1310) at kernel/qcoreapplication.cpp:1056
#41 0x00007fc04847983c in QApplicationPrivate::notify_helper (this=this@entry=0x1d4adc0, receiver=receiver@entry=0x295e9d0, e=e@entry=0x7fffb57c1310) at kernel/qapplication.cpp:4558
#42 0x00007fc04847e54b in QApplication::notify (this=<optimized out>, receiver=0x295e9d0, e=0x7fffb57c1310) at kernel/qapplication.cpp:4105
#43 0x00007fc04dadfcb6 in KApplication::notify (this=0x7fffb57c3310, receiver=0x295e9d0, event=0x7fffb57c1310) at /usr/src/debug/kdelibs-4.10.0/kdeui/kernel/kapplication.cpp:311
#44 0x00007fc0492ebc9e in QCoreApplication::notifyInternal (this=0x7fffb57c3310, receiver=0x295e9d0, event=0x7fffb57c1310) at kernel/qcoreapplication.cpp:946
#45 0x00007fc04847a6ab in sendEvent (event=<optimized out>, receiver=<optimized out>) at ../../src/corelib/kernel/qcoreapplication.h:231
#46 QApplicationPrivate::sendMouseEvent (receiver=0x295e9d0, event=0x7fffb57c1310, alienWidget=0x0, nativeWidget=0x295e9d0, buttonDown=0x7fc048f4e268 <qt_button_down>, lastMouseReceiver=..., spontaneous=true) at kernel/qapplication.cpp:3173
#47 0x00007fc0484f4e94 in QETWidget::translateMouseEvent (this=this@entry=0x295e9d0, event=event@entry=0x7fffb57c1a90) at kernel/qapplication_x11.cpp:4527
#48 0x00007fc0484f3c21 in QApplication::x11ProcessEvent (this=0x7fffb57c3310, event=0x7fffb57c1a90) at kernel/qapplication_x11.cpp:3650
#49 0x00007fc04851a9d9 in QEventDispatcherX11::processEvents (this=0x1d4ad50, flags=...) at kernel/qeventdispatcher_x11.cpp:132
#50 0x00007fc0492ea9ef in QEventLoop::processEvents (this=this@entry=0x25ec780, flags=...) at kernel/qeventloop.cpp:149
#51 0x00007fc0492eac78 in QEventLoop::exec (this=0x25ec780, flags=...) at kernel/qeventloop.cpp:204
#52 0x00007fc048501d26 in QDragManager::drag (this=0x2f3cb60, o=<optimized out>) at kernel/qdnd_x11.cpp:2028
#53 0x00007fc04848ace8 in QDrag::exec (this=0x378d560, supportedActions=..., defaultDropAction=defaultDropAction@entry=Qt::IgnoreAction) at kernel/qdrag.cpp:284
#54 0x00007fc04848ada3 in QDrag::exec (this=<optimized out>, supportedActions=...) at kernel/qdrag.cpp:239
#55 0x00007fc031b9adf8 in ?? () from /usr/lib64/kde4/kwin3_oxygen.so
#56 0x00007fc031b940b4 in ?? () from /usr/lib64/kde4/kwin3_oxygen.so
#57 0x00007fc0492ebe06 in QCoreApplicationPrivate::sendThroughObjectEventFilters (this=<optimized out>, receiver=0x31b7ad0, event=0x7fffb57c2630) at kernel/qcoreapplication.cpp:1056
#58 0x00007fc04847983c in QApplicationPrivate::notify_helper (this=this@entry=0x1d4adc0, receiver=receiver@entry=0x31b7ad0, e=e@entry=0x7fffb57c2630) at kernel/qapplication.cpp:4558
#59 0x00007fc04847e54b in QApplication::notify (this=<optimized out>, receiver=0x31b7ad0, e=0x7fffb57c2630) at kernel/qapplication.cpp:4105
#60 0x00007fc04dadfcb6 in KApplication::notify (this=0x7fffb57c3310, receiver=0x31b7ad0, event=0x7fffb57c2630) at /usr/src/debug/kdelibs-4.10.0/kdeui/kernel/kapplication.cpp:311
#61 0x00007fc0492ebc9e in QCoreApplication::notifyInternal (this=0x7fffb57c3310, receiver=0x31b7ad0, event=0x7fffb57c2630) at kernel/qcoreapplication.cpp:946
#62 0x00007fc04847a6ab in sendEvent (event=<optimized out>, receiver=<optimized out>) at ../../src/corelib/kernel/qcoreapplication.h:231
#63 QApplicationPrivate::sendMouseEvent (receiver=0x31b7ad0, event=0x7fffb57c2630, alienWidget=0x0, nativeWidget=0x31b7ad0, buttonDown=0x7fc048f4e268 <qt_button_down>, lastMouseReceiver=..., spontaneous=true) at kernel/qapplication.cpp:3173
#64 0x00007fc0484f4e94 in QETWidget::translateMouseEvent (this=this@entry=0x31b7ad0, event=event@entry=0x7fffb57c2db0) at kernel/qapplication_x11.cpp:4527
#65 0x00007fc0484f3c21 in QApplication::x11ProcessEvent (this=0x7fffb57c3310, event=0x7fffb57c2db0) at kernel/qapplication_x11.cpp:3650
#66 0x00007fc04851a9d9 in QEventDispatcherX11::processEvents (this=0x1d4ad50, flags=...) at kernel/qeventdispatcher_x11.cpp:132
#67 0x00007fc0492ea9ef in QEventLoop::processEvents (this=this@entry=0x7fffb57c3020, flags=...) at kernel/qeventloop.cpp:149
#68 0x00007fc0492eac78 in QEventLoop::exec (this=0x7fffb57c3020, flags=...) at kernel/qeventloop.cpp:204
#69 0x00007fc0492ef918 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1218
#70 0x00007fc04e31697a in kdemain () from /usr/lib64/libkdeinit4_kwin.so
#71 0x00007fc04df20a15 in __libc_start_main (main=0x400730, argc=3, ubp_av=0x7fffb57c3458, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fffb57c3448) at libc-start.c:258
#72 0x0000000000400761 in _start ()

Possible duplicates by query: bug 305544, bug 305493, bug 297152, bug 265622, bug 261776.

Reported using DrKonqi

Comment 1 Tilman Vogel 2013-04-11 10:36:00 UTC

Most of the time, the described interaction does not lead to the observed crash.

Comment 2 Thomas Lübking 2013-04-11 10:53:30 UTC

Long standing Qt DnD issue - as soon as there's eg. a tooltip below the DnD and vanishes, the DnD will crash the DnD receiver below and or anything else. (I frankly don't know what you were dragging where having the panel drag cause a crash in KWin - it looks more like you were dragging a window tab?)

Comment 3 Tilman Vogel 2013-04-11 13:29:59 UTC

Created attachment 78803 [details]
Screenshot "window buttons"

I dragged one of those guys from the panel.

Comment 4 Thomas Lübking 2013-04-11 13:43:50 UTC

#51 0x00007fc0492eac78 in QEventLoop::exec (this=0x25ec780, flags=...) at kernel/qeventloop.cpp:204
#52 0x00007fc048501d26 in QDragManager::drag (this=0x2f3cb60, o=<optimized out>) at kernel/qdnd_x11.cpp:2028
#53 0x00007fc04848ace8 in QDrag::exec (this=0x378d560, supportedActions=..., defaultDropAction=defaultDropAction@entry=Qt::IgnoreAction) at kernel/qdrag.cpp:284
#54 0x00007fc04848ada3 in QDrag::exec (this=<optimized out>, supportedActions=...) at kernel/qdrag.cpp:239
#55 0x00007fc031b9adf8 in ?? () from /usr/lib64/kde4/kwin3_oxygen.so
#56 0x00007fc031b940b4 in ?? () from /usr/lib64/kde4/kwin3_oxygen.so

Ok, my only guess then would be that the original drag "exited" preliminary (did plasma, ie. the panel, crash as well?), the X11 event got reposted and implicitly triggered a DnD on the (randomly below) tabs leading to this crash.