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 x86_64
Distribution: Ubuntu 11.04

-- Information about the crash:
- What I was doing when the application crashed:

I was simply trying to restore my PC from screensaver. The login window appeared partially but I was able to enter my password.
The screensaver stopped and I was notified that also KWin stopped.

The crash can be reproduced every time.

-- Backtrace:
Application: KWin (kwin), signal: Segmentation fault
[Current thread is 1 (Thread 0x7f3ec64537a0 (LWP 1566))]

Thread 3 (Thread 0x7f3ea6d60700 (LWP 1571)):
#0  0x00007f3ec5c9a143 in select () at ../sysdeps/unix/syscall-template.S:82
#1  0x00007f3ec207832c in qt_safe_select (nfds=15, fdread=0x2f21ba0, fdwrite=0x2f21e38, fdexcept=0x2f220d0, orig_timeout=<value optimized out>) at kernel/qcore_unix.cpp:82
#2  0x00007f3ec207d3d0 in QEventDispatcherUNIXPrivate::doSelect (this=0x2f219e0, flags=..., timeout=0x0) at kernel/qeventdispatcher_unix.cpp:219
#3  0x00007f3ec207e04a in QEventDispatcherUNIX::processEvents (this=0x2cfe620, flags=...) at kernel/qeventdispatcher_unix.cpp:919
#4  0x00007f3ec204f882 in QEventLoop::processEvents (this=<value optimized out>, flags=...) at kernel/qeventloop.cpp:149
#5  0x00007f3ec204fabc in QEventLoop::exec (this=0x7f3ea6d5fdb0, flags=...) at kernel/qeventloop.cpp:201
#6  0x00007f3ec1f66924 in QThread::exec (this=<value optimized out>) at thread/qthread.cpp:492
#7  0x00007f3ec2031c2f in QInotifyFileSystemWatcherEngine::run (this=0x2cfdaf0) at io/qfilesystemwatcher_inotify.cpp:248
#8  0x00007f3ec1f69175 in QThreadPrivate::start (arg=0x2cfdaf0) at thread/qthread_unix.cpp:320
#9  0x00007f3ebc658d8c in start_thread (arg=0x7f3ea6d60700) at pthread_create.c:304
#10 0x00007f3ec5ca204d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#11 0x0000000000000000 in ?? ()

Thread 2 (Thread 0x7f3ea655f700 (LWP 1572)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:162
#1  0x00007f3ec4b012a2 in QTWTF::TCMalloc_PageHeap::scavengerThread (this=0x7f3ec4e1a180) at ../3rdparty/javascriptcore/JavaScriptCore/wtf/FastMalloc.cpp:2359
#2  0x00007f3ec4b012d9 in QTWTF::TCMalloc_PageHeap::runScavengerThread (context=0x7f3ec4e28254) at ../3rdparty/javascriptcore/JavaScriptCore/wtf/FastMalloc.cpp:1464
#3  0x00007f3ebc658d8c in start_thread (arg=0x7f3ea655f700) at pthread_create.c:304
#4  0x00007f3ec5ca204d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#5  0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7f3ec64537a0 (LWP 1566)):
[KCrash Handler]
#6  intel_region_buffer (intel=0x1a2b750, region=0x0, flag=2) at intel_regions.c:514
#7  0x00007f3eadb3e6c2 in intelClearWithBlit (ctx=0x1a2b750, mask=2) at intel_blit.c:262
#8  0x00007f3eadb40d2a in intelClear (ctx=0x1a2b750, mask=2) at intel_clear.c:177
#9  0x00007f3ec6018ce7 in KWin::SceneOpenGL::paintBackground (this=<value optimized out>, region=<value optimized out>) at ../../kwin/scene_opengl.cpp:921
#10 0x00007f3ec601088f in KWin::Scene::paintGenericScreen (this=0x18febd0, orig_mask=40) at ../../kwin/scene.cpp:188
#11 0x00007f3ec600dc7a in KWin::Scene::finalPaintScreen (this=0x18febd0, mask=40, region=<value optimized out>, data=<value optimized out>) at ../../kwin/scene.cpp:178
#12 0x00007f3ec602bf19 in KWin::EffectsHandlerImpl::paintScreen (this=0x2b3cb60, mask=40, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:173
#13 0x00007f3eacc065a6 in KWin::StartupFeedbackEffect::paintScreen (this=0x2ff3b10, mask=40, region=<value optimized out>, data=...) at ../../../kwin/effects/startupfeedback/startupfeedback.cpp:166
#14 0x00007f3ec602bfa3 in KWin::EffectsHandlerImpl::paintScreen (this=0x2b3cb60, mask=40, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:169
#15 0x00007f3ec40eba18 in KWin::Effect::paintScreen (this=<value optimized out>, mask=40, region=<value optimized out>, data=...) at ../../../kwin/lib/kwineffects.cpp:227
#16 0x00007f3ec602bfa3 in KWin::EffectsHandlerImpl::paintScreen (this=0x2b3cb60, mask=40, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:169
#17 0x00007f3eacbad44d in KWin::LogoutEffect::paintScreen (this=0x2f18b10, mask=40, region=..., data=...) at ../../../kwin/effects/logout/logout.cpp:207
#18 0x00007f3ec602bfa3 in KWin::EffectsHandlerImpl::paintScreen (this=0x2b3cb60, mask=40, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:169
#19 0x00007f3eacbc857b in KWin::ShadowEffect::paintScreen (this=0x2b80570, mask=40, region=..., data=...) at ../../../kwin/effects/shadow/shadow.cpp:189
#20 0x00007f3ec602bfa3 in KWin::EffectsHandlerImpl::paintScreen (this=0x2b3cb60, mask=40, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:169
#21 0x00007f3eacbdae68 in KWin::BlurEffect::paintScreen (this=<value optimized out>, mask=40, region=..., data=...) at ../../../kwin/effects/blur/blur.cpp:230
#22 0x00007f3ec602bfa3 in KWin::EffectsHandlerImpl::paintScreen (this=0x2b3cb60, mask=8, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:169
#23 0x00007f3eacbb1fbd in KWin::PresentWindowsEffect::paintScreen (this=0x2b8a820, mask=8, region=..., data=...) at ../../../kwin/effects/presentwindows/presentwindows.cpp:205
#24 0x00007f3ec602bfa3 in KWin::EffectsHandlerImpl::paintScreen (this=0x2b3cb60, mask=8, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:169
#25 0x00007f3ec40eba18 in KWin::Effect::paintScreen (this=<value optimized out>, mask=8, region=<value optimized out>, data=...) at ../../../kwin/lib/kwineffects.cpp:227
#26 0x00007f3ec602bfa3 in KWin::EffectsHandlerImpl::paintScreen (this=0x2b3cb60, mask=8, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:169
#27 0x00007f3ec40eba18 in KWin::Effect::paintScreen (this=<value optimized out>, mask=8, region=<value optimized out>, data=...) at ../../../kwin/lib/kwineffects.cpp:227
#28 0x00007f3ec602bfa3 in KWin::EffectsHandlerImpl::paintScreen (this=0x2b3cb60, mask=8, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:169
#29 0x00007f3ec40eba18 in KWin::Effect::paintScreen (this=<value optimized out>, mask=8, region=<value optimized out>, data=...) at ../../../kwin/lib/kwineffects.cpp:227
#30 0x00007f3ec602bfa3 in KWin::EffectsHandlerImpl::paintScreen (this=0x2b3cb60, mask=8, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:169
#31 0x00007f3ec40eba18 in KWin::Effect::paintScreen (this=<value optimized out>, mask=8, region=<value optimized out>, data=...) at ../../../kwin/lib/kwineffects.cpp:227
#32 0x00007f3ec602bfa3 in KWin::EffectsHandlerImpl::paintScreen (this=0x2b3cb60, mask=8, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:169
#33 0x00007f3eacb99365 in KWin::DesktopGridEffect::paintScreen (this=0x2bbdc70, mask=8, region=..., data=...) at ../../../kwin/effects/desktopgrid/desktopgrid.cpp:155
#34 0x00007f3ec602bfa3 in KWin::EffectsHandlerImpl::paintScreen (this=0x2b3cb60, mask=8, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:169
#35 0x00007f3eacbceb8f in KWin::SlideEffect::paintScreen (this=<value optimized out>, mask=8, region=..., data=...) at ../../../kwin/effects/slide/slide.cpp:86
#36 0x00007f3ec602bfa3 in KWin::EffectsHandlerImpl::paintScreen (this=0x2b3cb60, mask=8, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:169
#37 0x00007f3eacb92bad in KWin::BoxSwitchEffect::paintScreen (this=0x2ea23d0, mask=8, region=..., data=...) at ../../../kwin/effects/boxswitch/boxswitch.cpp:143
#38 0x00007f3ec602bfa3 in KWin::EffectsHandlerImpl::paintScreen (this=0x2b3cb60, mask=8, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:169
#39 0x00007f3eacbe9256 in KWin::CubeEffect::paintScreen (this=<value optimized out>, mask=8, region=..., data=...) at ../../../kwin/effects/cube/cube.cpp:698
#40 0x00007f3ec602bfa3 in KWin::EffectsHandlerImpl::paintScreen (this=0x2b3cb60, mask=8, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:169
#41 0x00007f3ec40eba18 in KWin::Effect::paintScreen (this=<value optimized out>, mask=8, region=<value optimized out>, data=...) at ../../../kwin/lib/kwineffects.cpp:227
#42 0x00007f3ec602bfa3 in KWin::EffectsHandlerImpl::paintScreen (this=0x2b3cb60, mask=8, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:169
#43 0x00007f3ec40eba18 in KWin::Effect::paintScreen (this=<value optimized out>, mask=8, region=<value optimized out>, data=...) at ../../../kwin/lib/kwineffects.cpp:227
#44 0x00007f3ec602bfa3 in KWin::EffectsHandlerImpl::paintScreen (this=0x2b3cb60, mask=8, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:169
#45 0x00007f3ec40eba18 in KWin::Effect::paintScreen (this=<value optimized out>, mask=8, region=<value optimized out>, data=...) at ../../../kwin/lib/kwineffects.cpp:227
#46 0x00007f3ec602bfa3 in KWin::EffectsHandlerImpl::paintScreen (this=0x2b3cb60, mask=8, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:169
#47 0x00007f3eacbe1d86 in KWin::CoverSwitchEffect::paintScreen (this=0x2fa1f70, mask=8, region=..., data=...) at ../../../kwin/effects/coverswitch/coverswitch.cpp:126
#48 0x00007f3ec602bfa3 in KWin::EffectsHandlerImpl::paintScreen (this=0x2b3cb60, mask=8, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:169
#49 0x00007f3ec40eba18 in KWin::Effect::paintScreen (this=<value optimized out>, mask=8, region=<value optimized out>, data=...) at ../../../kwin/lib/kwineffects.cpp:227
#50 0x00007f3ec602bfa3 in KWin::EffectsHandlerImpl::paintScreen (this=0x2b3cb60, mask=8, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:169
#51 0x00007f3ec40eba18 in KWin::Effect::paintScreen (this=<value optimized out>, mask=8, region=<value optimized out>, data=...) at ../../../kwin/lib/kwineffects.cpp:227
#52 0x00007f3ec602bfa3 in KWin::EffectsHandlerImpl::paintScreen (this=0x2b3cb60, mask=8, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:169
#53 0x00007f3eacbd839b in KWin::ZoomEffect::paintScreen (this=0x2ddbdd0, mask=8, region=..., data=...) at ../../../kwin/effects/zoom/zoom.cpp:341
#54 0x00007f3ec602bfa3 in KWin::EffectsHandlerImpl::paintScreen (this=0x2b3cb60, mask=8, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:169
#55 0x00007f3ec60100af in KWin::Scene::paintScreen (this=0x18febd0, mask=0x7fffcc3cc33c, region=0x7fffcc3cc420) at ../../kwin/scene.cpp:137
#56 0x00007f3ec6023ef3 in KWin::SceneOpenGL::paint (this=0x18febd0, damage=..., toplevels=<value optimized out>) at ../../kwin/scene_opengl.cpp:772
#57 0x00007f3ec600b275 in KWin::Workspace::performCompositing (this=0x7f3ea8353c50) at ../../kwin/composite.cpp:442
#58 0x00007f3ec20641c9 in QObject::event (this=0x7f3ea8353c50, e=<value optimized out>) at kernel/qobject.cpp:1190
#59 0x00007f3ec140d9f4 in QApplicationPrivate::notify_helper (this=0x17e2870, receiver=0x7f3ea8353c50, e=0x7fffcc3ccb90) at kernel/qapplication.cpp:4462
#60 0x00007f3ec14123ba in QApplication::notify (this=<value optimized out>, receiver=0x7f3ea8353c50, e=0x7fffcc3ccb90) at kernel/qapplication.cpp:4341
#61 0x00007f3ec579d866 in KApplication::notify (this=0x7fffcc3ccf90, receiver=0x7f3ea8353c50, event=0x7fffcc3ccb90) at ../../kdeui/kernel/kapplication.cpp:311
#62 0x00007f3ec205049c in QCoreApplication::notifyInternal (this=0x7fffcc3ccf90, receiver=0x7f3ea8353c50, event=0x7fffcc3ccb90) at kernel/qcoreapplication.cpp:731
#63 0x00007f3ec207df12 in sendEvent (this=0x17e4980) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:215
#64 QTimerInfoList::activateTimers (this=0x17e4980) at kernel/qeventdispatcher_unix.cpp:604
#65 0x00007f3ec207e05b in QEventDispatcherUNIX::processEvents (this=0x1787340, flags=...) at kernel/qeventdispatcher_unix.cpp:923
#66 0x00007f3ec14b82ec in QEventDispatcherX11::processEvents (this=0x1787340, flags=...) at kernel/qeventdispatcher_x11.cpp:152
#67 0x00007f3ec204f882 in QEventLoop::processEvents (this=<value optimized out>, flags=...) at kernel/qeventloop.cpp:149
#68 0x00007f3ec204fabc in QEventLoop::exec (this=0x7fffcc3cced0, flags=...) at kernel/qeventloop.cpp:201
#69 0x00007f3ec2053ecb in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1008
#70 0x00007f3ec5fa91ec in kdemain (argc=<value optimized out>, argv=0x7fffcc3cd628) at ../../kwin/main.cpp:542
#71 0x00007f3ec5bdaeff in __libc_start_main (main=0x400740 <main(int, char**)>, argc=3, ubp_av=0x7fffcc3cd628, init=<value optimized out>, fini=<value optimized out>, rtld_fini=<value optimized out>, stack_end=0x7fffcc3cd618) at libc-start.c:226
#72 0x0000000000400669 in _start ()

Possible duplicates by query: bug 277753, bug 277463, bug 277203, bug 276860, bug 276797.

Reported using DrKonqi