(In reply to Zbigniew Luszpinski from comment #30)
> Just apply only one of these solutions. I prefer to add my GPU to exclusion
> list "drm/radeon: Ignore RADEON_GEM_GTT_WC on Kabini" patch instead of
> patching mesa.

While that patch works around the problem, it doesn't make much sense
conceptually: Since everything is working fine with 64-bit kernels, there
doesn't seem to be anything wrong with any particular GPUs.

Also, disabling write-combining decreases performance.

For those reasons, until someone figures out the root cause of this problem,
IMHO the preferred workaround is to run a 64-bit kernel. Any particular reason
why you can't do that?