Application: krita (2.2 Alpha 1)
KDE Platform Version: 4.3.80 (KDE 4.3.80 (KDE 4.4 Beta1))
Qt Version: 4.6.0
Operating System: Linux 2.6.32-9-generic x86_64
Distribution: Ubuntu lucid (development branch)

-- Information about the crash:
I was using the smudge brush with a tablet (although it only shows to X as a mouse). I'd been smudging quite a lot with a 30px size brush when suddenly Krita crashed. I'd also had something similar happen with the spray brush, but can't say if that's the same crash, or a different one.

 -- Backtrace:
Application: Krita (krita), signal: Segmentation fault
[Current thread is 1 (Thread 0x7fc51315b830 (LWP 22073))]

Thread 3 (Thread 0x7fc501e2b910 (LWP 22092)):
#0  0x00007fc5128895a9 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#1  0x00007fc512b1466b in QWaitCondition::wait(QMutex*, unsigned long) () from /usr/lib/libQtCore.so.4
#2  0x00007fc512b105a0 in QSemaphore::acquire(int) () from /usr/lib/libQtCore.so.4
#3  0x00007fc5120a0b5e in KisTileDataPooler::waitForWork (this=0x7fc5123f4500) at /home/user/source/koffice/krita/image/tiles3/kis_tile_data_pooler.cc:120
#4  0x00007fc5120a0f48 in KisTileDataPooler::run (this=0x7fc5123f4500) at /home/user/source/koffice/krita/image/tiles3/kis_tile_data_pooler.cc:149
#5  0x00007fc512b136b5 in ?? () from /usr/lib/libQtCore.so.4
#6  0x00007fc512884a04 in start_thread () from /lib/libpthread.so.0
#7  0x00007fc50af4f05d in clone () from /lib/libc.so.6
#8  0x0000000000000000 in ?? ()

Thread 2 (Thread 0x7fc4f0dff910 (LWP 22385)):
[KCrash Handler]
#5  0x00007fc51212dc51 in KisSharedPtr (this=<value optimized out>) at /home/user/source/koffice/krita/image/kis_shared_ptr.h:94
#6  KisNode::firstChild (this=<value optimized out>) at /home/user/source/koffice/krita/image/kis_node.cpp:132
#7  0x00007fc512109d25 in KisGroupLayer::tryObligeChild (this=0x173c550) at /home/user/source/koffice/krita/image/kis_group_layer.cc:109
#8  0x00007fc51210a9ba in KisGroupLayer::repaintOriginal (this=0x173c550, original=) at /home/user/source/koffice/krita/image/kis_group_layer.cc:144
#9  0x00007fc5121234a3 in KisLayer::updateProjection (this=0x173c550, rect=<value optimized out>) at /home/user/source/koffice/krita/image/kis_layer.cc:360
#10 0x00007fc51214ecb4 in KisImageUpdater::update (this=0x166e880, node=) at /home/user/source/koffice/krita/image/kis_projection.cc:174
#11 0x00007fc51214edb6 in KisImageUpdater::update (this=0x166e880, node=<value optimized out>, child=) at /home/user/source/koffice/krita/image/kis_projection.cc:183
#12 0x00007fc51214f3a0 in KisImageUpdater::startUpdate (this=0x166e880, node=<value optimized out>, rc=...) at /home/user/source/koffice/krita/image/kis_projection.cc:156
#13 0x00007fc51214f4bd in KisImageUpdater::qt_metacall (this=0x166e880, _c=QMetaObject::InvokeMetaMethod, _id=1, _a=0x1bb121f0) at /home/user/Apps/koffice/build/krita/image/kis_projection.moc:144
#14 0x00007fc512c16789 in QObject::event(QEvent*) () from /usr/lib/libQtCore.so.4
#15 0x00007fc50c275f2c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#16 0x00007fc50c27c53d in QApplication::notify(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#17 0x00007fc50d7407d6 in KApplication::notify(QObject*, QEvent*) () from /usr/lib/libkdeui.so.5
#18 0x00007fc512c06abc in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/libQtCore.so.4
#19 0x00007fc512c09237 in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () from /usr/lib/libQtCore.so.4
#20 0x00007fc512c338a0 in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#21 0x00007fc512c053e2 in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#22 0x00007fc512c057bc in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#23 0x00007fc512b10c79 in QThread::exec() () from /usr/lib/libQtCore.so.4
#24 0x00007fc512b136b5 in ?? () from /usr/lib/libQtCore.so.4
#25 0x00007fc512884a04 in start_thread () from /lib/libpthread.so.0
#26 0x00007fc50af4f05d in clone () from /lib/libc.so.6
#27 0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7fc51315b830 (LWP 22073)):
#0  0x00007fc50af42c13 in poll () from /lib/libc.so.6
#1  0x00007fc50865d29a in ?? () from /usr/lib/libxcb.so.1
#2  0x00007fc50865d7d7 in ?? () from /usr/lib/libxcb.so.1
#3  0x00007fc50865da85 in xcb_writev () from /usr/lib/libxcb.so.1
#4  0x00007fc510eba80a in _XSend () from /usr/lib/libX11.so.6
#5  0x00007fc510ebad31 in _XEventsQueued () from /usr/lib/libX11.so.6
#6  0x00007fc510ea34cd in XPending () from /usr/lib/libX11.so.6
#7  0x00007fc50c2fa18f in ?? () from /usr/lib/libQtGui.so.4
#8  0x00007fc50c2f8d6a in QApplication::x11ProcessEvent(_XEvent*) () from /usr/lib/libQtGui.so.4
#9  0x00007fc50c3250f9 in ?? () from /usr/lib/libQtGui.so.4
#10 0x00007fc512c053e2 in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#11 0x00007fc512c057bc in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#12 0x00007fc512c094fb in QCoreApplication::exec() () from /usr/lib/libQtCore.so.4
#13 0x00007fc512f1dc05 in kdemain (argc=<value optimized out>, argv=<value optimized out>) at /home/user/source/koffice/krita/main.cc:49
#14 0x00007fc50ae8dadd in __libc_start_main () from /lib/libc.so.6
#15 0x0000000000400909 in _start ()

Reported using DrKonqi