PageTableMap() only modifies the PageTable root pointer when creating from zero. Explicitly explain it in function header. Reviewed-by: Ray Ni <ray.ni@intel.com> Reviewed-by: Laszlo Ersek <lersek@redhat.com> Cc: Rahul Kumar <rahul1.kumar@intel.com> Cc: Gerd Hoffmann <kraxel@redhat.com> Signed-off-by: Zhiguang Liu <zhiguang.liu@intel.com>