I get lotsa (128 in dmesg) "radeon 0000:01:00.0: vbo resource seems too big (32769) for the bo (32768)" with glxgears atm and machine slows down to a crawl. I suspect related to this http://www.spinics.net/lists/dri-devel/msg03278.html off-by-one discussion. Considering the version of DRM I have seems to have the line "size = radeon_get_ib_value(p, idx+1+(i*7)+1) + 1;" and agd5f claims the patch in the link was wrong, this could hint that r600g has the size wrong. Mesa 90437330e2886fcd351dd11ee0e5aa3e8b523fdc.
Pushed fix
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