Thanks summerrainbowz, I had no idea that was supposed to be for the Kernel. I
can also confirm summerrainbowz's results. My dmesg output looks different
though.

My setup current is Fedora 23. I compiled and installed mesa, xf86-video-ati,
and drm from git master. I also applied the "Tahiti fix v2" patch to vanilla
Kernel 4.2 to test. Kernel config settings were identical to Fedora's config. I
took out nomodeset from grub boot parameters when testing as well. I am
uploading the attached Xorg and dmesg logs.