How do I attach a debugger? (I have just restarted kded4 so it's now working but I can reboot the machine so that I have faulty kded4 again.)

Please see for information on how to generate a backtrace - https://wiki.debian.org/HowToGetABacktrace#Running_gdb
You can use this command to attach a debugger to your currently running kded4 process:

Code: Select all

gdb --attach $(pidof kded4)

The output of gdb bt command: (full output of gdb http://pastebin.com/wppVcFgG )

Code: Select all

(gdb) bt
#0  0x00007f5f588c7286 in ppoll () from /lib64/libc.so.6
#1  0x00007f5f488e9417 in pa_mainloop_poll () from /usr/lib64/libpulse.so.0
#2  0x00007f5f488e99e9 in pa_mainloop_iterate () from /usr/lib64/libpulse.so.0
#3  0x00007f5f249e0d6f in ?? () from /usr/lib64/kde4/kded_kmixd.so
#4  0x00007f5f249e12b4 in ?? () from /usr/lib64/kde4/kded_kmixd.so
#5  0x00007f5f249ef01f in ?? () from /usr/lib64/kde4/kded_kmixd.so
#6  0x00007f5f249f6cce in ?? () from /usr/lib64/kde4/kded_kmixd.so
#7  0x00007f5f249f7e5a in ?? () from /usr/lib64/kde4/kded_kmixd.so
#8  0x00007f5f249f7f0e in ?? () from /usr/lib64/kde4/kded_kmixd.so
#9  0x00007f5f249eb88b in ?? () from /usr/lib64/kde4/kded_kmixd.so
#10 0x00007f5f249ec3f7 in ?? () from /usr/lib64/kde4/kded_kmixd.so
#11 0x00007f5f5a435285 in KPluginFactory::create(char const*, QWidget*, QObject*, QList<QVariant> const&, QString const&) () from /usr/lib64/libkdecore.so.5
#12 0x00007f5f4533dd29 in ?? () from /usr/lib64/libkdeinit4_kded4.so
#13 0x00007f5f4533eab2 in ?? () from /usr/lib64/libkdeinit4_kded4.so
#14 0x00007f5f45341025 in ?? () from /usr/lib64/libkdeinit4_kded4.so
#15 0x00007f5f4534123b in ?? () from /usr/lib64/libkdeinit4_kded4.so
#16 0x00007f5f56c3bf01 in ?? () from /usr/lib64/qt4/libQtDBus.so.4
#17 0x00007f5f56c3cf8d in ?? () from /usr/lib64/qt4/libQtDBus.so.4
#18 0x00007f5f56c3d9ab in ?? () from /usr/lib64/qt4/libQtDBus.so.4
#19 0x00007f5f56c3da9b in ?? () from /usr/lib64/qt4/libQtDBus.so.4
#20 0x00007f5f59ed6b5e in QObject::event(QEvent*) () from /usr/lib64/qt4/libQtCore.so.4
#21 0x00007f5f5906fd6c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib64/qt4/libQtGui.so.4
#22 0x00007f5f590726db in QApplication::notify(QObject*, QEvent*) () from /usr/lib64/qt4/libQtGui.so.4
#23 0x00007f5f5ac837d6 in KApplication::notify(QObject*, QEvent*) () from /usr/lib64/libkdeui.so.5
#24 0x00007f5f59ebd26e in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib64/qt4/libQtCore.so.4
#25 0x00007f5f59ec0881 in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () from /usr/lib64/qt4/libQtCore.so.4
#26 0x00007f5f59eeb523 in ?? () from /usr/lib64/qt4/libQtCore.so.4
#27 0x00007f5f557ca5f5 in g_main_context_dispatch () from /usr/lib64/libglib-2.0.so.0
#28 0x00007f5f557ca938 in ?? () from /usr/lib64/libglib-2.0.so.0
#29 0x00007f5f557ca9f4 in g_main_context_iteration () from /usr/lib64/libglib-2.0.so.0
#30 0x00007f5f59eeb6b6 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib64/qt4/libQtCore.so.4
#31 0x00007f5f5911008e in ?? () from /usr/lib64/qt4/libQtGui.so.4
#32 0x00007f5f59ebbf1f in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib64/qt4/libQtCore.so.4
#33 0x00007f5f59ebc1a8 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib64/qt4/libQtCore.so.4
#34 0x00007f5f59ec13e8 in QCoreApplication::exec() () from /usr/lib64/qt4/libQtCore.so.4
#35 0x00007f5f4533d770 in kdemain () from /usr/lib64/libkdeinit4_kded4.so
#36 0x000000000040894a in _start ()


Ah, KMixD again. Please see viewtopic.php?f=224&t=119224&p=300313&hilit=kmixd#p300313.

I have to resurrect this thread once again. This issue with KDED4 not starting correctly is still happening on my system. Even after the latest update of KDE. I have tried to delete kmix files ~/.kde4/share/config but this doesn't really help, the kded4 still hangs for about 25% boots.
Do you have any other ideas?

Can you verify that it is KMixD causing this? Gdb as used above should be able to verify if this is the case.
If it is, then you should uncheck KMixD in System Settings > Startup & Shutdown > Service Manager.