get_user_seg
unsafe_put_user(get_user_seg(gs), (unsigned int __user *)&sc->gs, Efault);
unsafe_put_user(get_user_seg(fs), (unsigned int __user *)&sc->fs, Efault);
unsafe_put_user(get_user_seg(ds), (unsigned int __user *)&sc->ds, Efault);
unsafe_put_user(get_user_seg(es), (unsigned int __user *)&sc->es, Efault);