Comment # 8 on bug 103111 from Steve Falco

As per the mailing list suggestions, I've built a kernel from the
amd-staging-drm-next branch of the agd5f kernel tree.

While it gives me a usable gui, I also get "corrupted mapping in tail page"
errors.  Please see the dmesg attachment at
https://bugs.freedesktop.org/attachment.cgi?id=134713 for the details.