That's because the rawhide kernel you have installed is a
kernel. The kernel before that (3.5.0-0.rc0.git12 or something) is a
debug kernel and will have UAS enabled. The next git snapshot of
3.5.0-rc1 will also have it enabled.
Well, next is kernel-3.5.0-0.rc2.git0.1.fc18 which has UAS disabled too.
/me goes fetch 3.5.0-0.rc0.git12 now ...
We build one non-debug kernel in rawhide per RC release. You just
happened to hit it.
That scheme sucks big time. Why flip config options like that?
We have kernel-debug, why not enable options like UAS which are too
buggy for the default kernel there? Permanently?