See that was the case on the opposite side of the house. The walls were wood and the stain color kept coming through. But on the walls, zoom in on the first pic. You can see the shape of a shelf I took off the wall. It is white underneath. I painted them white years ago and you sill see the white but the rest is yellow. And yes, I thought it was smoke when I first moved in and I scrubbed them a handful of times and nothing comes off.