I keep running into this every time I switch away from X. Here's a stack trace with Qt debug symbols, in KDE 4.13.3:
#0 0x00007f7514c4f8e3 in select () at ../sysdeps/unix/syscall-template.S:81 #1 0x00007f750f0401c7 in qt_safe_select (nfds=23, fdread=0xcf7f88, fdwrite=0xcf8220, fdexcept=0xcf84b8, orig_timeout=0x7fff4a848190) at kernel/qcore_unix.cpp:89 #2 0x00007f750f045824 in QEventDispatcherUNIXPrivate::doSelect (this=this@entry=0xcf7dd0, flags=..., timeout=0x7fff4a848190) at kernel/qeventdispatcher_unix.cpp:223 #3 0x00007f750f045c92 in QEventDispatcherUNIX::processEvents (this=this@entry=0xc98af0, flags=...) at kernel/qeventdispatcher_unix.cpp:936 #4 0x00007f750e4514d6 in QEventDispatcherX11::processEvents (this=0xc98af0, flags=...) at kernel/qeventdispatcher_x11.cpp:152 #5 0x00007f750f0140af in QEventLoop::processEvents (this=this@entry=0x7fff4a848460, flags=...) at kernel/qeventloop.cpp:149 #6 0x00007f750f0143a5 in QEventLoop::exec (this=this@entry=0x7fff4a848460, flags=...) at kernel/qeventloop.cpp:204 #7 0x00007f750f019b79 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1225 #8 0x00007f750e3ad37c in QApplication::exec () at kernel/qapplication.cpp:3828 #9 0x00007f7514f9e9d6 in kdemain (argc=3, argv=0x7fff4a848738) at ../../kwin/main.cpp:597 #10 0x00007f7514b7eec5 in __libc_start_main (main=0x4006d0 <main(int, char**)>, argc=3, argv=0x7fff4a848738, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fff4a848728) at libc-start.c:287 #11 0x00000000004006fe in _start () -- You received this bug notification because you are a member of Kubuntu Bugs, which is subscribed to kde-workspace in Ubuntu. https://bugs.launchpad.net/bugs/1272438 Title: kwin 100% of cpu, second session To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/kde-workspace/+bug/1272438/+subscriptions -- kubuntu-bugs mailing list kubuntu-b...@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/kubuntu-bugs