Bug 355686

Thanks for the bug report. Could you try to get a backtrace while Dolphin freezes? See https://community.kde.org/Dolphin/FAQ/Freeze for details. Thanks!

here is the backtrace:

gdb dolphin
GNU gdb (GDB; openSUSE Factory) 7.9
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Reading symbols from dolphin...(no debugging symbols found)...done.
Missing separate debuginfos, use: zypper install dolphin-debuginfo-15.08.2-3.1.x86_64
(gdb) run
Starting program: /usr/bin/dolphin 
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
"Trying to convert empty KLocalizedString to QString."
Detaching after fork from child process 18285.
Detaching after fork from child process 18288.
Detaching after fork from child process 18289.
QProcess: Destroyed while process ("/usr/bin/baloo_filemetadata_temp_extractor") is still running.
Detaching after fork from child process 18290.
QProcess: Destroyed while process ("/usr/bin/baloo_filemetadata_temp_extractor") is still running.
^Z[New Thread 0x7fffd5317700 (LWP 18281)]                                                                                    
[New Thread 0x7fffe0d2c700 (LWP 18280)]                                                                                      
                                                                                                                             
Program received signal SIGTSTP, Stopped (user).                                                                             
0x00007ffff78471cd in poll () from /lib64/libc.so.6                                                                          
(gdb) thread apply all backtrace                                                                                             
                                                                                                                             
Thread 3 (Thread 0x7fffe0d2c700 (LWP 18280)):
#0  0x00007ffff78471cd in poll () at /lib64/libc.so.6
#1  0x00007fffeaadd432 in  () at /usr/lib64/libxcb.so.1
#2  0x00007fffeaadf007 in xcb_wait_for_event () at /usr/lib64/libxcb.so.1
#3  0x00007fffe307fe29 in  () at /usr/lib64/libQt5XcbQpa.so.5
#4  0x00007ffff1c3c94f in  () at /usr/lib64/libQt5Core.so.5
#5  0x00007fffed61c4a4 in start_thread () at /lib64/libpthread.so.0
#6  0x00007ffff784fb5d in clone () at /lib64/libc.so.6

Thread 2 (Thread 0x7fffd5317700 (LWP 18281)):
#0  0x00007ffff78471cd in poll () at /lib64/libc.so.6
#1  0x00007fffecee8264 in  () at /usr/lib64/libglib-2.0.so.0
#2  0x00007fffecee836c in g_main_context_iteration () at /usr/lib64/libglib-2.0.so.0
#3  0x00007ffff1e6150f in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) ()
    at /usr/lib64/libQt5Core.so.5
#4  0x00007ffff1e0b63a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib64/libQt5Core.so.5
#5  0x00007ffff1c37b1c in QThread::exec() () at /usr/lib64/libQt5Core.so.5
#6  0x00007ffff1c3c94f in  () at /usr/lib64/libQt5Core.so.5
#7  0x00007fffed61c4a4 in start_thread () at /lib64/libpthread.so.0
#8  0x00007ffff784fb5d in clone () at /lib64/libc.so.6

Thread 1 (Thread 0x7ffff7f7c8c0 (LWP 18276)):
#0  0x00007ffff78471cd in poll () at /lib64/libc.so.6
#1  0x00007fffebfed4c4 in  () at /lib64/libdbus-1.so.3
#2  0x00007fffebfec3f8 in  () at /lib64/libdbus-1.so.3
#3  0x00007fffebfd65d4 in  () at /lib64/libdbus-1.so.3
#4  0x00007fffebfd708c in  () at /lib64/libdbus-1.so.3
#5  0x00007fffebfd753d in dbus_connection_send_with_reply_and_block () at /lib64/libdbus-1.so.3
#6  0x00007ffff2280c20 in  () at /usr/lib64/libQt5DBus.so.5
#7  0x00007ffff226ef13 in QDBusConnection::call(QDBusMessage const&, QDBus::CallMode, int) const ()
    at /usr/lib64/libQt5DBus.so.5
#8  0x00007ffff42277b1 in KToolInvocation::startServiceInternal(char const*, QString const&, QStringList const&, QString*, QString*, int*, QByteArray const&, bool, QString const&) () at /usr/lib64/libKF5Service.so.5
#9  0x00007ffff422815c in KToolInvocation::startServiceByDesktopPath(QString const&, QStringList const&, QString*, QString*, int*, QByteArray const&, bool) () at /usr/lib64/libKF5Service.so.5
#10 0x00007ffff60db344 in KRun::runService(KService const&, QList<QUrl> const&, QWidget*, bool, QString const&, QByteArray const&) () at /usr/lib64/libKF5KIOWidgets.so.5
#11 0x00007ffff60de748 in KRun::runUrl(QUrl const&, QString const&, QWidget*, bool, bool, QString const&, QByteArray const&) () at /usr/lib64/libKF5KIOWidgets.so.5
#12 0x00007ffff60def5a in KRun::foundMimeType(QString const&) () at /usr/lib64/libKF5KIOWidgets.so.5
#13 0x00007ffff60d8ed2 in KRun::mimeTypeDetermined(QString const&) () at /usr/lib64/libKF5KIOWidgets.so.5
#14 0x00007ffff60d8f4c in KRun::scanFile() () at /usr/lib64/libKF5KIOWidgets.so.5
#15 0x00007ffff60df95d in KRun::slotTimeout() () at /usr/lib64/libKF5KIOWidgets.so.5
#16 0x00007ffff1e3af8a in QMetaObject::activate(QObject*, int, int, void**) () at /usr/lib64/libQt5Core.so.5
#17 0x00007ffff1e470e8 in QTimer::timerEvent(QTimerEvent*) () at /usr/lib64/libQt5Core.so.5
---Type <return> to continue, or q <return> to quit---
#18 0x00007ffff1e3bd2b in QObject::event(QEvent*) () at /usr/lib64/libQt5Core.so.5
#19 0x00007ffff2f7f8cc in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib64/libQt5Widgets.so.5
#20 0x00007ffff2f849d6 in QApplication::notify(QObject*, QEvent*) () at /usr/lib64/libQt5Widgets.so.5
#21 0x00007ffff1e0dcf3 in QCoreApplication::notifyInternal(QObject*, QEvent*) () at /usr/lib64/libQt5Core.so.5
#22 0x00007ffff1e603bd in QTimerInfoList::activateTimers() () at /usr/lib64/libQt5Core.so.5
#23 0x00007ffff1e608d1 in  () at /usr/lib64/libQt5Core.so.5
#24 0x00007fffecee8097 in g_main_context_dispatch () at /usr/lib64/libglib-2.0.so.0
#25 0x00007fffecee82c8 in  () at /usr/lib64/libglib-2.0.so.0
#26 0x00007fffecee836c in g_main_context_iteration () at /usr/lib64/libglib-2.0.so.0
#27 0x00007ffff1e6150f in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) ()
    at /usr/lib64/libQt5Core.so.5
#28 0x00007ffff1e0b63a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib64/libQt5Core.so.5
#29 0x00007ffff1e132fd in QCoreApplication::exec() () at /usr/lib64/libQt5Core.so.5
#30 0x00007ffff7b6a641 in kdemain () at /usr/lib64/libkdeinit5_dolphin.so
#31 0x00007ffff7786610 in __libc_start_main () at /lib64/libc.so.6
#32 0x00000000004007f9 in _start ()

Thanks for the quick reply. Looks like a KService issue that has been reported already.

*** This bug has been marked as a duplicate of bug 353037 ***