Same here: 4.1.1.2 Arch Linux build-2 | KDE 4.11.1.
To unfreeze could be done I used Ctrl+Alt+F1 and then Ctrl+Alt+F7. Finally removed libreoffice-kde package (LO KDE desktop integration) and now can't reproduce freezing.
Same here: 4.1.1.2 Arch Linux build-2 | KDE 4.11.1.
To unfreeze could be done I used Ctrl+Alt+F1 and then Ctrl+Alt+F7. Finally removed libreoffice-kde package (LO KDE desktop integration) and now can't reproduce freezing.