I’ve had a few issues getting my mouse working properly with evdev in the latest updates to Slackware64-current. Today, it appears, that other users are experiencing some other issues outside of a mouse not mapping buttons properly. Most of those users report black screens when trying to restart or quit an X session.
If you are one of us having such issues and are stumped, try the below in your xorg.conf before you go googling around for 3 hours like I did
Option "AutoAddDevices" "False"
Option "AllowEmptyInput" "False"
I hope this helps!
As always you can catch me in ##slackware on freenode if you have any questions/suggestions/comments.