So I was looking at my header photo which is a wall in my Dining area and it shows a Flat " D" interior wall.
The photos below are from a round interior home and as you can see you can still hang things from the wall. In this first photo it shows a log wall on the right side with window and door and then the wall that the fireplace is on is an interior wall with log siding on it but they both match up and look the same.
In this photo you can see how you connect an interior sheet rock wall with the round log wall. Also notice how again the home owner used a great old chest to become the vanity of the 2 bathroom sinks.