Okular Freeze

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Reading symbols from okular...(no debugging symbols found)...done.
(gdb) run
Starting program: /usr/bin/okular
warning: Could not load shared library symbols for linux-vdso.so.1.
Do you need "set solib-search-path" or "set sysroot"?
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/usr/lib/libthread_db.so.1".
okular(30507)/kdecore (KConfigSkeleton) KCoreConfigSkeleton::writeConfig:
okular(30507)/kdecore (KConfigSkeleton) KCoreConfigSkeleton::writeConfig:
okular(30507)/kdecore (KConfigSkeleton) KCoreConfigSkeleton::writeConfig:
okular(30507)/kdecore (KConfigSkeleton) KCoreConfigSkeleton::writeConfig:
okular(30507)/kdecore (KConfigSkeleton) KCoreConfigSkeleton::writeConfig:
^C
Program received signal SIGINT, Interrupt.
0x00007ffff4f9d800 in __poll_nocancel () from /usr/lib/libc.so.6
(gdb) thread apply all bt

Thread 1 (Thread 0x7ffff7f87780 (LWP 30507)):
#0  0x00007ffff4f9d800 in __poll_nocancel () from /usr/lib/libc.so.6
#1  0x00007fffe155e29e in httpAddrConnect2 () from /usr/lib/libcups.so.2
#2  0x00007fffe155d0ca in httpReconnect2 () from /usr/lib/libcups.so.2
#3  0x00007fffe155d1cf in httpConnect2 () from /usr/lib/libcups.so.2
#4  0x00007fffe157928e in _cupsConnect () from /usr/lib/libcups.so.2
#5  0x00007fffe1579f71 in cupsDoIORequest () from /usr/lib/libcups.so.2
#6  0x00007fffe154e0f3 in _cupsGetDests () from /usr/lib/libcups.so.2
#7  0x00007fffe154f21c in cupsGetDests2 () from /usr/lib/libcups.so.2
#8  0x00007ffff657af3c in ?? () from /usr/lib/libQtGui.so.4
#9  0x00007ffff657b085 in ?? () from /usr/lib/libQtGui.so.4
#10 0x00007ffff64d691b in ?? () from /usr/lib/libQtGui.so.4
#11 0x00007ffff64ebf2b in ?? () from /usr/lib/libQtGui.so.4
#12 0x00007ffff64edfc7 in ?? () from /usr/lib/libQtGui.so.4
#13 0x00007ffff64ef524 in QPrinter::init(QPrinter::PrinterMode) () from /usr/lib/libQtGui.so.4
#14 0x00007ffff64f06e2 in QPrinter::QPrinter(QPrinter::PrinterMode) () from /usr/lib/libQtGui.so.4
#15 0x00007fffe671cb1e in ?? () from /lib64/libokularcore.so.4
#16 0x00007fffe671d535 in ?? () from /lib64/libokularcore.so.4
#17 0x00007fffe671d779 in Okular::Document::pageSizeString(int) const () from /lib64/libokularcore.so.4
#18 0x00007fffe6a2e6a9 in ?? () from /usr/lib/kde4/okularpart.so
#19 0x00007fffe671dad7 in Okular::Document::setViewport(Okular::DocumentViewport const&, Okular::DocumentObserver*, bool) ()
   from /lib64/libokularcore.so.4
#20 0x00007fffe6729cd7 in Okular::Document::openDocument(QString const&, KUrl const&, KSharedPtr<KMimeType> const&) ()
   from /lib64/libokularcore.so.4
#21 0x00007fffe69ee509 in Okular::Part::openFile() () from /usr/lib/kde4/okularpart.so
#22 0x00007ffff7babf17 in ?? () from /usr/lib/libkparts.so.4
#23 0x00007ffff7bad4fe in KParts::ReadOnlyPart::openUrl(KUrl const&) () from /usr/lib/libkparts.so.4
#24 0x00007fffe69e4a5b in Okular::Part::openUrl(KUrl const&) () from /usr/lib/kde4/okularpart.so
#25 0x000000000040eb11 in _start ()