0xffffe410 in __kernel_vsyscall () (gdb) bt #0 0xffffe410 in __kernel_vsyscall () #1 0xb7d87e1e in __lll_mutex_lock_wait () from /lib/tls/i686/cmov/libpthread.so.0 #2 0xb7d83b68 in _L_mutex_lock_86 () from /lib/tls/i686/cmov/libpthread.so.0 #3 0xb7d8358d in pthread_mutex_lock () from /lib/tls/i686/cmov/libpthread.so.0 #4 0xb70d8c06 in ?? () from /usr/lib/libQtCore.so.4 #5 0x083ad3ac in ?? () #6 0xb7214e20 in ?? () from /usr/lib/libQtCore.so.4 #7 0xbfdf3658 in ?? () #8 0xb70d4689 in QMutex::unlock () from /usr/lib/libQtCore.so.4 wtf?