White walls and ceiling in my shop too, makes for better lighting effect as they're bright and reflective.
In my preivous shop (commercial setting) I had the lower 2' or so painted a light-medium gray so nasty dirt wouldn't show. I was surprised at how much brighter things are with all-white.
I have a black with black/white checkerboard (well, checkered flag

) motiff for the the garage bath wall tile, but I want pretty plain styling in the shop. Less distracting visually and I just like the nothing-fancy/functional look. Anything other than the plain glossy white would cut down on the bright reflectiveness too.
My floor is a mottled gray (epoxy/stone material) and sometimes the "busy-ness" of it makes it hard to find dropped stuff, especially small items that blend in with the look of the floor. A plain light gray would've been better in that regard.