My S6 just updated to Marshmallow (6.0.1, Sprint) today and now I can't use my fingerprint scanner on the lock screen. Whenever I would hit the power button, I would have to dismiss the alert to "Make sure the home key is clean and dry" TWICE before I could then enter a PIN or my backup password. Tried clearing the system cache etc. Have not tried a full restore, which I don't have time for. Ugh.
Very bummed.
Very bummed.