Application: kwin (4.6.2 (4.6.2))
KDE Platform Version: 4.6.2 (4.6.2)
Qt Version: 4.7.2
Operating System: Linux 2.6.38-10-generic i686
Distribution: Ubuntu 11.04

-- Information about the crash:
- What I was doing when the application crashed:
Enter the desktop grid effect (the system had just been booted) 
Move the mouse from one empty desktop to the other => kwin sigdev

The crash can be reproduced some of the time.

-- Backtrace:
Application: KWin (kwin), signal: Segmentation fault
[Current thread is 1 (Thread 0xb5e0d720 (LWP 1716))]

Thread 3 (Thread 0xb1250b70 (LWP 1729)):
#0  0x00c0e416 in __kernel_vsyscall ()
#1  0x00259681 in select () from /lib/i386-linux-gnu/libc.so.6
#2  0x07d0538b in qt_safe_select (nfds=21, fdread=0x9155810, fdwrite=0x9155a24, fdexcept=0x9155c38, orig_timeout=0x0) at kernel/qcore_unix.cpp:82
#3  0x07d096e9 in QEventDispatcherUNIX::select (this=0x908e0e8, nfds=21, readfds=0x9155810, writefds=0x9155a24, exceptfds=0x9155c38, timeout=0x0) at kernel/qeventdispatcher_unix.cpp:632
#4  0x07d0a66b in QEventDispatcherUNIXPrivate::doSelect (this=0x9155718, flags=..., timeout=0x0) at kernel/qeventdispatcher_unix.cpp:219
#5  0x07d0b326 in QEventDispatcherUNIX::processEvents (this=0x908e0e8, flags=...) at kernel/qeventdispatcher_unix.cpp:919
#6  0x07cda289 in QEventLoop::processEvents (this=0xb1250280, flags=...) at kernel/qeventloop.cpp:149
#7  0x07cda522 in QEventLoop::exec (this=0xb1250280, flags=...) at kernel/qeventloop.cpp:201
#8  0x07be42a0 in QThread::exec (this=0x9056700) at thread/qthread.cpp:492
#9  0x07cbbfdb in QInotifyFileSystemWatcherEngine::run (this=0x9056700) at io/qfilesystemwatcher_inotify.cpp:248
#10 0x07be6da2 in QThreadPrivate::start (arg=0x9056700) at thread/qthread_unix.cpp:320
#11 0x07ac1e99 in start_thread () from /lib/i386-linux-gnu/libpthread.so.0
#12 0x0026073e in clone () from /lib/i386-linux-gnu/libc.so.6

Thread 2 (Thread 0xb0a47b70 (LWP 1730)):
#0  0x00c0e416 in __kernel_vsyscall ()
#1  0x07ac648c in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/i386-linux-gnu/libpthread.so.0
#2  0x0026e3fd in pthread_cond_wait () from /lib/i386-linux-gnu/libc.so.6
#3  0x008c4817 in QTWTF::TCMalloc_PageHeap::scavengerThread (this=0x9d81c0) at ../3rdparty/javascriptcore/JavaScriptCore/wtf/FastMalloc.cpp:2359
#4  0x008c4851 in QTWTF::TCMalloc_PageHeap::runScavengerThread (context=0x9d81c0) at ../3rdparty/javascriptcore/JavaScriptCore/wtf/FastMalloc.cpp:1464
#5  0x07ac1e99 in start_thread () from /lib/i386-linux-gnu/libpthread.so.0
#6  0x0026073e in clone () from /lib/i386-linux-gnu/libc.so.6

Thread 1 (Thread 0xb5e0d720 (LWP 1716)):
[KCrash Handler]
#7  0x00000000 in ?? ()
#8  0x0433dc90 in KWin::DesktopGridEffect::windowInputMouseEvent (this=0x8fc7248, e=0xbfd7ebb8) at ../../../kwin/effects/desktopgrid/desktopgrid.cpp:544
#9  0x0070ba99 in KWin::EffectsHandlerImpl::checkInputWindowEvent (this=0x8e5a498, e=0xbfd7f10c) at ../../kwin/effects.cpp:926
#10 0x00699090 in KWin::Workspace::workspaceEvent (this=0xb3571040, e=0xbfd7f10c) at ../../kwin/events.cpp:262
#11 0x00672b02 in KWin::Application::x11EventFilter (this=0xbfd7f2f4, e=0xbfd7f10c) at ../../kwin/main.cpp:367
#12 0x025c9e14 in qt_x11EventFilter (ev=0xbfd7f10c) at kernel/qapplication_x11.cpp:440
#13 0x025db887 in QApplication::x11ProcessEvent (this=0xbfd7f2f4, event=0xbfd7f10c) at kernel/qapplication_x11.cpp:3392
#14 0x02609150 in QEventDispatcherX11::processEvents (this=0x8c70aa8, flags=...) at kernel/qeventdispatcher_x11.cpp:132
#15 0x07cda289 in QEventLoop::processEvents (this=0xbfd7f234, flags=...) at kernel/qeventloop.cpp:149
#16 0x07cda522 in QEventLoop::exec (this=0xbfd7f234, flags=...) at kernel/qeventloop.cpp:201
#17 0x07cdeecc in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1008
#18 0x0254f8e7 in QApplication::exec () at kernel/qapplication.cpp:3736
#19 0x006755b2 in kdemain (argc=1, argv=0xbfd7f574) at ../../kwin/main.cpp:542
#20 0x080485bb in main (argc=1, argv=0xbfd7f574) at kwin_dummy.cpp:3

This bug may be a duplicate of or related to bug 253942.

Possible duplicates by query: bug 272928, bug 272370, bug 267562, bug 262893, bug 253942.

Reported using DrKonqi