Thanks for the bug report! The backtrace does not tell us much about the cause of the freeze. It only has some information about the termination by xkill. Can you try to reproduce the freeze and provide a backtrace, as described in https://community.kde.org/Dolphin/FAQ/Freeze? This would tell us which part of the code (which might not be in Dolphin at all, but in some library) is responsible for the freeze. Thanks!

(In reply to Frank Reininghaus from comment #1)
> Thanks for the bug report! The backtrace does not tell us much about the
> cause of the freeze. It only has some information about the termination by
> xkill. Can you try to reproduce the freeze and provide a backtrace, as
> described in https://community.kde.org/Dolphin/FAQ/Freeze? This would tell
> us which part of the code (which might not be in Dolphin at all, but in some
> library) is responsible for the freeze. Thanks!

Here is a backtrace I made with your instruction

[michaelgeh@The-Ruler ~]$ gdb dolphin
GNU gdb (GDB) Fedora 7.7.1-22.fc20
Copyright (C) 2014 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-redhat-linux-gnu".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
<http://www.gnu.org/software/gdb/documentation/>.
For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from dolphin...Reading symbols from /usr/lib/debug/usr/bin/dolphin.debug...done.
done.
(gdb) run
Starting program: /usr/bin/dolphin 
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
Traceback (most recent call last):
  File "/usr/share/gdb/auto-load/usr/lib64/libgobject-2.0.so.0.3800.2-gdb.py", line 9, in <module>
    from gobject import register
  File "/usr/share/glib-2.0/gdb/gobject.py", line 3, in <module>
    import gdb.backtrace
ImportError: No module named backtrace
Traceback (most recent call last):
  File "/usr/share/gdb/auto-load/usr/lib64/libgobject-2.0.so.0.3800.2-gdb.py", line 9, in <module>
    from gobject import register
  File "/usr/share/glib-2.0/gdb/gobject.py", line 3, in <module>
    import gdb.backtrace
ImportError: No module named backtrace
[New Thread 0x7fffed160700 (LWP 26388)]
[New Thread 0x7fffec8b5700 (LWP 26391)]
[New Thread 0x7fffe7adf700 (LWP 26393)]
Detaching after fork from child process 26394.
dolphin(26372)/konsole Konsole::Session::run: Attempted to re-run an already running session. 
dolphin(26372) KMimeTypePrivate::ensureXmlDataLoaded: Missing <comment> field in "application/x-wine-extension-key.xml" 
Detaching after fork from child process 26430.
Detaching after fork from child process 26443.
QInotifyFileSystemWatcherEngine::addPaths: inotify_add_watch failed: Datei oder Verzeichnis nicht gefunden
[New Thread 0x7fffe6c00700 (LWP 26444)]
QFileSystemWatcher: failed to add paths: /home/michaelgeh/.dropbox/aggregation.dbx
[New Thread 0x7fffe61e3700 (LWP 26504)]
Detaching after fork from child process 26505.
Detaching after fork from child process 26506.
[Thread 0x7fffe61e3700 (LWP 26504) exited]
[New Thread 0x7fffe61e3700 (LWP 26512)]
Detaching after fork from child process 26513.
Detaching after fork from child process 26514.
[Thread 0x7fffe61e3700 (LWP 26512) exited]
[New Thread 0x7fffe61e3700 (LWP 26517)]
Detaching after fork from child process 26518.
Detaching after fork from child process 26519.
[Thread 0x7fffe61e3700 (LWP 26517) exited]
[New Thread 0x7fffe61e3700 (LWP 26524)]
Detaching after fork from child process 26525.
Detaching after fork from child process 26526.
[Thread 0x7fffe61e3700 (LWP 26524) exited]
[New Thread 0x7fffe61e3700 (LWP 26527)]
Detaching after fork from child process 26528.
Detaching after fork from child process 26529.
[Thread 0x7fffe61e3700 (LWP 26527) exited]
[New Thread 0x7fffe61e3700 (LWP 26534)]
Detaching after fork from child process 26535.
Detaching after fork from child process 26536.
[Thread 0x7fffe61e3700 (LWP 26534) exited]
[New Thread 0x7fffe61e3700 (LWP 26537)]
Detaching after fork from child process 26538.
Detaching after fork from child process 26539.
[Thread 0x7fffe61e3700 (LWP 26537) exited]
[New Thread 0x7fffe61e3700 (LWP 26542)]
Detaching after fork from child process 26543.
Detaching after fork from child process 26544.
[Thread 0x7fffe61e3700 (LWP 26542) exited]
[New Thread 0x7fffe61e3700 (LWP 26545)]
Detaching after fork from child process 26546.
Detaching after fork from child process 26547.
[Thread 0x7fffe61e3700 (LWP 26545) exited]
UdevQt: unhandled device action "move"
[New Thread 0x7fffe61e3700 (LWP 27134)]
Detaching after fork from child process 27135.
Detaching after fork from child process 27136.
[Thread 0x7fffe61e3700 (LWP 27134) exited]
[New Thread 0x7fffe61e3700 (LWP 27137)]
Detaching after fork from child process 27138.
Detaching after fork from child process 27139.
[Thread 0x7fffe61e3700 (LWP 27137) exited]
UdevQt: unhandled device action "move"
[New Thread 0x7fffe61e3700 (LWP 27449)]
Detaching after fork from child process 27450.
Detaching after fork from child process 27451.
[Thread 0x7fffe61e3700 (LWP 27449) exited]
[New Thread 0x7fffe61e3700 (LWP 27452)]
Detaching after fork from child process 27453.
Detaching after fork from child process 27454.
[Thread 0x7fffe61e3700 (LWP 27452) exited]
[New Thread 0x7fffe61e3700 (LWP 27457)]
Detaching after fork from child process 27458.
Detaching after fork from child process 27459.
[Thread 0x7fffe61e3700 (LWP 27457) exited]
[New Thread 0x7fffe61e3700 (LWP 27485)]
Detaching after fork from child process 27486.
Detaching after fork from child process 27487.
[Thread 0x7fffe61e3700 (LWP 27485) exited]
[New Thread 0x7fffe61e3700 (LWP 27488)]
Detaching after fork from child process 27489.
Detaching after fork from child process 27490.
[Thread 0x7fffe61e3700 (LWP 27488) exited]
UdevQt: unhandled device action "move"
UdevQt: unhandled device action "move"
^Zthread apply all backtrace
^Z^Z
Program received signal SIGTSTP, Stopped (user).
[Switching to Thread 0x7fffed160700 (LWP 26388)]
0x00000033812ea8ad in poll () at ../sysdeps/unix/syscall-template.S:81
81      T_PSEUDO (SYSCALL_SYMBOL, SYSCALL_NAME, SYSCALL_NARGS)
Missing separate debuginfos, use: debuginfo-install OpenEXR-libs-1.7.1-6.fc20.x86_64 appmenu-qt-0.2.6-4.fc20.x86_64 attica-0.4.2-2.fc20.x86_64 bzip2-libs-1.0.6-9.fc20.x86_64 dbus-libs-1.6.30-1.fc20.x86_64 dbusmenu-qt-0.9.2-5.fc20.x86_64 dolphin-plugins-14.12.3-1.fc20.x86_64 expat-2.1.0-7.fc20.x86_64 flac-libs-1.3.1-1.fc20.x86_64 fontconfig-2.11.0-2.fc20.x86_64 freetype-2.5.0-10.fc20.x86_64 gamin-0.1.10-15.fc20.x86_64 glib2-2.38.2-2.fc20.x86_64 gsm-1.0.13-10.fc20.x86_64 gstreamer-0.10.36-7.fc20.x86_64 gstreamer-plugins-base-0.10.36-7.fc20.x86_64 herqq-1.0.0-6.fc20.x86_64 ilmbase-1.0.3-7.fc20.x86_64 jasper-libs-1.900.1-28.fc20.x86_64 jbigkit-libs-2.0-10.fc20.x86_64 json-c-0.11-6.fc20.x86_64 kde-runtime-libs-15.04.0-1.fc20.x86_64 kde-style-oxygen-4.11.18-3.fc20.x86_64 kde-workspace-libs-4.11.18-3.fc20.x86_64 keyutils-libs-1.5.9-1.fc20.x86_64 kfilemetadata-4.14.3-1.fc20.x86_64 konsole-part-4.14.3-4.fc20.x86_64 krb5-libs-1.11.5-19.fc20.x86_64 lcms-libs-1.19-13.fc20.x86_64 libICE-1.0.8-6.fc20.x86_64 libSM-1.2.1-6.fc20.x86_64 libX11-1.6.1-1.fc20.x86_64 libXScrnSaver-1.2.2-6.fc20.x86_64 libXau-1.0.8-2.fc20.x86_64 libXcursor-1.1.14-2.fc20.x86_64 libXdamage-1.1.4-4.fc20.x86_64 libXdmcp-1.1.1-5.fc20.x86_64 libXext-1.3.2-2.fc20.x86_64 libXfixes-5.0.1-2.fc20.x86_64 libXft-2.3.1-5.fc20.x86_64 libXi-1.7.4-1.fc20.x86_64 libXinerama-1.1.3-2.fc20.x86_64 libXpm-3.5.10-5.fc20.x86_64 libXrandr-1.4.1-2.fc20.x86_64 libXrender-0.9.8-2.fc20.x86_64 libXtst-1.2.2-2.fc20.x86_64 libXxf86vm-1.1.3-2.fc20.x86_64 libacl-2.2.52-4.fc20.x86_64 libasyncns-0.8-6.fc20.x86_64 libattr-2.4.47-3.fc20.x86_64 libcap-2.22-7.fc20.x86_64 libcom_err-1.42.12-4.fc20.x86_64 libdrm-2.4.58-1.fc20.x86_64 libffi-3.0.13-5.fc20.x86_64 libgcrypt-1.5.3-2.fc20.x86_64 libgpg-error-1.12-1.fc20.x86_64 libicu-50.1.2-12.fc20.x86_64 libjpeg-turbo-1.3.1-3.fc20.x86_64 libmng-1.0.10-12.fc20.x86_64 libogg-1.3.0-6.fc20.x86_64 libpng-1.6.6-3.fc20.x86_64 libqzeitgeist-0.8.0-10.fc20.x86_64 libselinux-2.2.1-6.fc20.x86_64 libsndfile-1.0.25-9.fc20.x86_64 libtiff-4.0.3-15.fc20.x86_64 libutempter-1.1.6-3.fc20.x86_64 libuuid-2.24.2-2.fc20.x86_64 libvorbis-1.3.4-1.fc20.x86_64 libwebp-0.3.1-3.fc20.x86_64 libxcb-1.9.1-3.fc20.x86_64 libxml2-2.9.1-4.fc20.x86_64 libxslt-1.1.28-5.fc20.x86_64 mesa-libGL-10.3.5-1.20141207.fc20.x86_64 mesa-libglapi-10.3.5-1.20141207.fc20.x86_64 openssl-libs-1.0.1e-42.fc20.x86_64 orc-0.4.22-2.fc20.x86_64 pcre-8.33-10.fc20.x86_64 proj-4.8.0-5.fc20.x86_64 pulseaudio-libs-5.0-25.fc20.x86_64 pulseaudio-libs-glib2-5.0-25.fc20.x86_64 qca2-2.0.3-6.fc20.x86_64 qjson-0.8.1-3.fc20.x86_64 qt-mobility-location-1.2.2-0.16.20140317git169da60c.fc20.x86_64 qt-mobility-sensors-1.2.2-0.16.20140317git169da60c.fc20.x86_64 qtsoap-2.7-6.fc20.x86_64 qtwebkit-2.3.4-6.fc20.x86_64 soprano-2.9.4-2.fc20.x86_64 sqlite-3.8.9-1.fc20.x86_64 strigi-libs-0.7.8-2.fc20.x86_64 systemd-libs-208-31.fc20.x86_64 tcp_wrappers-libs-7.6-76.fc20.x86_64 xapian-core-libs-1.2.20-1.fc20.x86_64 xz-libs-5.1.2-12alpha.fc20.x86_64 zlib-1.2.8-3.fc20.x86_64
(gdb)  
(gdb) thread apply all backtrace

Thread 5 (Thread 0x7fffe6c00700 (LWP 26444)):
#0  0x00000033812ea8ad in poll () at ../sysdeps/unix/syscall-template.S:81
#1  0x00000033836495b4 in g_main_context_iterate.isra () from /lib64/libglib-2.0.so.0
#2  0x00000033836496dc in g_main_context_iteration () from /lib64/libglib-2.0.so.0
#3  0x0000003b3c1b541e in QEventDispatcherGlib::processEvents (this=0x7fffd40008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:452
#4  0x0000003b3c18536f in QEventLoop::processEvents (this=this@entry=0x7fffe6bffc40, flags=...) at kernel/qeventloop.cpp:149
#5  0x0000003b3c1856bd in QEventLoop::exec (this=this@entry=0x7fffe6bffc40, flags=...) at kernel/qeventloop.cpp:204
#6  0x0000003b3c079e5f in QThread::exec (this=this@entry=0xc11c60) at thread/qthread.cpp:538
#7  0x0000003b3c165dc3 in QInotifyFileSystemWatcherEngine::run (this=0xc11c60) at io/qfilesystemwatcher_inotify.cpp:265
#8  0x0000003b3c07c69f in QThreadPrivate::start (arg=0xc11c60) at thread/qthread_unix.cpp:349
#9  0x0000003381a07ee5 in start_thread (arg=0x7fffe6c00700) at pthread_create.c:309
#10 0x00000033812f4d1d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111

Thread 4 (Thread 0x7fffe7adf700 (LWP 26393)):
#0  0x00000033812ea8ad in poll () at ../sysdeps/unix/syscall-template.S:81
#1  0x0000003b3c1b2c68 in poll (__timeout=-1, __nfds=1, __fds=0x7fffe7adeca0) at /usr/include/bits/poll2.h:46
#2  qt_safe_poll (fds=fds@entry=0x7fffe7adeca0, nfds=nfds@entry=1, timeout_ms=timeout_ms@entry=-1, retry_eintr=retry_eintr@entry=false) at kernel/qcore_unix.cpp:117
#3  0x0000003b3c1625b8 in QProcessManager::run (this=0x3b3c4ed520 <processManager()::processManager>) at io/qprocess_unix.cpp:263
#4  0x0000003b3c07c69f in QThreadPrivate::start (arg=0x3b3c4ed520 <processManager()::processManager>) at thread/qthread_unix.cpp:349
#5  0x0000003381a07ee5 in start_thread (arg=0x7fffe7adf700) at pthread_create.c:309
#6  0x00000033812f4d1d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111

Thread 3 (Thread 0x7fffec8b5700 (LWP 26391)):
#0  0x00000033812ea8ad in poll () at ../sysdeps/unix/syscall-template.S:81
#1  0x00000033836495b4 in g_main_context_iterate.isra () from /lib64/libglib-2.0.so.0
#2  0x00000033836496dc in g_main_context_iteration () from /lib64/libglib-2.0.so.0
#3  0x0000003b3c1b53fe in QEventDispatcherGlib::processEvents (this=0x7fffe00008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:450
#4  0x0000003b3c18536f in QEventLoop::processEvents (this=this@entry=0x7fffec8b4c90, flags=...) at kernel/qeventloop.cpp:149
#5  0x0000003b3c1856bd in QEventLoop::exec (this=this@entry=0x7fffec8b4c90, flags=...) at kernel/qeventloop.cpp:204
#6  0x0000003b3c079e5f in QThread::exec (this=<optimized out>) at thread/qthread.cpp:538
#7  0x0000003b3c07c69f in QThreadPrivate::start (arg=0x8f0da0) at thread/qthread_unix.cpp:349
#8  0x0000003381a07ee5 in start_thread (arg=0x7fffec8b5700) at pthread_create.c:309
#9  0x00000033812f4d1d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111

Thread 2 (Thread 0x7fffed160700 (LWP 26388)):
#0  0x00000033812ea8ad in poll () at ../sysdeps/unix/syscall-template.S:81
#1  0x00000033836495b4 in g_main_context_iterate.isra () from /lib64/libglib-2.0.so.0
#2  0x00000033836496dc in g_main_context_iteration () from /lib64/libglib-2.0.so.0
#3  0x0000003b3c1b541e in QEventDispatcherGlib::processEvents (this=0x7fffe80008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:452
#4  0x0000003b3c18536f in QEventLoop::processEvents (this=this@entry=0x7fffed15fc40, flags=...) at kernel/qeventloop.cpp:149
#5  0x0000003b3c1856bd in QEventLoop::exec (this=this@entry=0x7fffed15fc40, flags=...) at kernel/qeventloop.cpp:204
#6  0x0000003b3c079e5f in QThread::exec (this=this@entry=0x9f7f50) at thread/qthread.cpp:538
#7  0x0000003b3c165dc3 in QInotifyFileSystemWatcherEngine::run (this=0x9f7f50) at io/qfilesystemwatcher_inotify.cpp:265
#8  0x0000003b3c07c69f in QThreadPrivate::start (arg=0x9f7f50) at thread/qthread_unix.cpp:349
#9  0x0000003381a07ee5 in start_thread (arg=0x7fffed160700) at pthread_create.c:309
#10 0x00000033812f4d1d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111

Thread 1 (Thread 0x7ffff7f6d940 (LWP 26372)):
#0  0x00000033812e6707 in access () at ../sysdeps/unix/syscall-template.S:81
#1  0x00000032271396e4 in access (mode=2, path=...) at /usr/src/debug/kdelibs-4.14.7/kdecore/util/kde_file.h:181
#2  KFileItem::isWritable (this=this@entry=0xe6dcb0) at /usr/src/debug/kdelibs-4.14.7/kio/kio/kfileitem.cpp:1119
#3  0x00000032271426d8 in KFileItemListPropertiesPrivate::setItems (this=0x1400c80, items=...) at /usr/src/debug/kdelibs-4.14.7/kio/kio/kfileitemlistproperties.cpp:94
#4  0x00000032304479a7 in DolphinMainWindow::updateEditActions (this=this@entry=0x7f38c0) at /usr/src/debug/kde-baseapps-15.04.0/dolphin/src/dolphinmainwindow.cpp:1309
---Type <return> to continue, or q <return> to quit---
#5  0x0000003230447cf5 in DolphinMainWindow::slotSelectionChanged (this=0x7f38c0, selection=...) at /usr/src/debug/kde-baseapps-15.04.0/dolphin/src/dolphinmainwindow.cpp:261
#6  0x0000003230447f91 in DolphinMainWindow::qt_static_metacall (_o=0x7f38c0, _id=<optimized out>, _a=<optimized out>, _c=<optimized out>)
    at /usr/src/debug/kde-baseapps-15.04.0/x86_64-redhat-linux-gnu/dolphin/src/dolphinmainwindow.moc:221
#7  0x0000003b3c19b35a in QMetaObject::activate (sender=sender@entry=0xa6dd90, m=m@entry=0x3230afa9a0 <DolphinView::staticMetaObject>, 
    local_signal_index=local_signal_index@entry=17, argv=argv@entry=0x7fffffffd1d0) at kernel/qobject.cpp:3567
#8  0x00000032308b4025 in DolphinView::selectionChanged (this=this@entry=0xa6dd90, _t1=...)
    at /usr/src/debug/kde-baseapps-15.04.0/x86_64-redhat-linux-gnu/dolphin/src/dolphinview.moc:443
#9  0x00000032308b533b in DolphinView::emitSelectionChangedSignal (this=0xa6dd90) at /usr/src/debug/kde-baseapps-15.04.0/dolphin/src/views/dolphinview.cpp:1114
#10 0x00000032308babe5 in DolphinView::qt_static_metacall (_o=<optimized out>, _id=<optimized out>, _a=0x7fffffffd2d0, _c=<optimized out>)
    at /usr/src/debug/kde-baseapps-15.04.0/x86_64-redhat-linux-gnu/dolphin/src/dolphinview.moc:259
#11 0x0000003b3c19b35a in QMetaObject::activate (sender=0xa6e390, m=<optimized out>, local_signal_index=<optimized out>, argv=0x0) at kernel/qobject.cpp:3567
#12 0x0000003b3c19f711 in QObject::event (this=0xa6e390, e=<optimized out>) at kernel/qobject.cpp:1184
#13 0x0000003b3c7cae6c in QApplicationPrivate::notify_helper (this=this@entry=0x65bd90, receiver=receiver@entry=0xa6e390, e=e@entry=0x7fffffffd740)
    at kernel/qapplication.cpp:4565
#14 0x0000003b3c7d17c5 in QApplication::notify (this=this@entry=0x7fffffffdb10, receiver=receiver@entry=0xa6e390, e=e@entry=0x7fffffffd740) at kernel/qapplication.cpp:4351
#15 0x0000003225e4a6ea in KApplication::notify (this=0x7fffffffdb10, receiver=0xa6e390, event=0x7fffffffd740) at /usr/src/debug/kdelibs-4.14.7/kdeui/kernel/kapplication.cpp:311
#16 0x0000003b3c1868dd in QCoreApplication::notifyInternal (this=0x7fffffffdb10, receiver=0xa6e390, event=event@entry=0x7fffffffd740) at kernel/qcoreapplication.cpp:953
#17 0x0000003b3c1b8143 in sendEvent (event=0x7fffffffd740, receiver=<optimized out>) at kernel/qcoreapplication.h:231
#18 QTimerInfoList::activateTimers (this=0x64efd0) at kernel/qeventdispatcher_unix.cpp:621
#19 0x0000003b3c1b5201 in timerSourceDispatch (source=<optimized out>) at kernel/qeventdispatcher_glib.cpp:193
#20 0x00000033836492a6 in g_main_context_dispatch () from /lib64/libglib-2.0.so.0
#21 0x0000003383649628 in g_main_context_iterate.isra () from /lib64/libglib-2.0.so.0
#22 0x00000033836496dc in g_main_context_iteration () from /lib64/libglib-2.0.so.0
#23 0x0000003b3c1b53fe in QEventDispatcherGlib::processEvents (this=0x61f6d0, flags=...) at kernel/qeventdispatcher_glib.cpp:450
#24 0x0000003b3c86ccd6 in QGuiEventDispatcherGlib::processEvents (this=<optimized out>, flags=...) at kernel/qguieventdispatcher_glib.cpp:207
#25 0x0000003b3c18536f in QEventLoop::processEvents (this=this@entry=0x7fffffffd9d0, flags=...) at kernel/qeventloop.cpp:149
#26 0x0000003b3c1856bd in QEventLoop::exec (this=this@entry=0x7fffffffd9d0, flags=...) at kernel/qeventloop.cpp:204
#27 0x0000003b3c18ad89 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1225
#28 0x0000003b3c7c94ec in QApplication::exec () at kernel/qapplication.cpp:3823
#29 0x0000003230453f91 in kdemain (argc=1, argv=0x7fffffffdc58) at /usr/src/debug/kde-baseapps-15.04.0/dolphin/src/main.cpp:93
#30 0x0000003381221d65 in __libc_start_main (main=0x4008b0 <main(int, char**)>, argc=1, argv=0x7fffffffdc58, init=<optimized out>, fini=<optimized out>, 
    rtld_fini=<optimized out>, stack_end=0x7fffffffdc48) at libc-start.c:285
#31 0x00000000004008e1 in _start ()

Hi Michael,
can you please test if changing the ssh timeout parameters (e.g. ServerAliveCountMax=1 and ServerAliveInterval=5) fixes/minimizes the problem for you? About 5 seconds after the connection is lost, Dolphin should become responsive again. Have a look at the ssh_config manpage or  http://www.johnhawthorn.com/2011/04/prevent-hanging-sshfs-connections/

Hi Emmanuel,

thank you that did it. But I think the bug still has a sense because in my mind that should not crash whole dolphin when ssh connection is lost.

It freezes in KFileItem::isWritable() from KIO, so I'll reassign the report there. Dolphin must know if the current location is writable in order to enable/disable the cut/paste actions correctly. A freeze can only be prevented if KIO provides a non-blocking API for this.

Well, this bug report makes me very happy, because it confirms what I've been saying for years: this issue is *exactly* why I'm opposed to solutions based on FUSE and other similar remote pseudo-filesystems.

KIO itself (when using proper kioslaves, not something that masquerades as a local filesystem) is asynchronous for this exact reason, so that it doesn't block the application, ever.

It's just unthinkable to make every local file usage non-blocking. The POSIX APIs were definitely not designed that way. See open/fopen, read, write, seek, etc. etc. Async local IO exists but is extremely cumbersome to use, and I'm pretty sure, non portable.
Test any non KDE software in the same setup (sshfs connection lost), and that software will freeze just the same way. Firefox, LibreOffice, gnome apps, etc. etc. The issue is sshfs, not the GUI apps on top.

=> use kio_sftp or kio_fish rather than a sshfs mount.

(i.e. a sftp:// or fish:// URL in dolphin)

Hi David,

I found it a bit odd that a bug makes you happy, but in any case, the reality is that FUSE exists and it can make Dolphin crash, so we should not ignore it. Also, your solution of using KIO is in my opinion, not practical:

- First of all, KIO is a KDE-only technology while FUSE works everywhere, so it is to be expected for FUSE to be more widespread. Unless we are doing only apps for Plasma and ignoring all the other desktops, we can't pretend FUSE doesn't exist.

- Second, and most important to me, is that KIO doesn't support some of the features that SSHFS does, and this is the reason why KDE Connect needs to use SSHFS [1]. This issue, together with this other one [2] is currently blocking the release of KDE Connect for Plasma 5. And it doesn't make me happy to see that this bug is "invalid" just because "use kio".

[1] https://github.com/albertvaka/kdeconnect-kde/blob/master/plugins/sftp/mounter.cpp#L127
[2] https://bugs.kde.org/show_bug.cgi?id=345199

Dolphin does not crash (until you killed it). It hangs. It hangs because you are asking it to use a hanging networked filesystem. That is NOT a dolphin/kde bug.

Did you test what I suggested earlier? Try the same issue (sshfs connection lost) in any non KDE software, and that software will freeze just the same way. Firefox, LibreOffice, gnome apps, etc. etc. The issue is sshfs, not the GUI apps on top.
Try navigating in LibreOffice's File-Open dialog (assuming no KDE integration is installed), and then pull the plug. It will hang, and you will end up killing it, just like you did with Dolphin.

Any networked mount has this issue, it's the price to pay in that type of solution.
So, OK, fine, don't use kio, use a networked mount but then don't pull the plug :)

I saw Solaris workstations hanging due to an unreachable NFS server... and 30 years later networked mounts still hang. Progress, heh? :-)

Really, all argumentation aside, there is nothing to fix here. Any synchronous file access will hang if the kernel makes it hang, it's the kernel that should somehow react faster when losing connection (but of course it has wait in order to be sure...).

I think we should at least fix this related issue [1]. As far as I know, Solid is able to detect remote mounts so we could use that information.

[1] https://bugs.kde.org/show_bug.cgi?id=349161

OK, then merging with 349161.

*** This bug has been marked as a duplicate of bug 349161 ***