It depends how bad the warping is. As long as you can hone it in such a way that you get the entire blade to contact the hone, maybe a rocking motion as you hone will do the trick. Some use the narrow hone approach also. If the warping is more severe the only choice you have is either cut the razor down in size or trash it. So the key is contact with the hone at an equal rate along the entire blade otherwise you'll really mess up the blade.