Last Year's Potato's

Hi all,
Been to tidy our allotment today (hard work)  , thing is i had mistakingly left 1 row of potatoes in the ground from last years harvest, i have dug them up and 90% are fine, rock hard, lovely pale yellow skin, a few with pest drill holes, my question to you guys is this, are these potatos edible?
Cheers Terry

Thanks, i thought that would be the case, but thought it best to ask the experts!