- - - Updated - - -
Yep . The white walkers are the ones that get killed by dragon glass and valyrian steel (as confirmed by last episode ) . They are turned to white walkers as childs as seen in the last minutes of an episode of last season , can't remember which one though .
I am thinking that valyrian steel and dragon glass may have the same origin , or that dragon glass can be forged by conventional or unconventional means (magic) to valyrian steel