https://bugs.freedesktop.org/show_bug.cgi?id=78453
--- Comment #42 from vincent vljn@ovi.com --- There is 4 calls to radeon_bo_map outside of si_get_backend_mask, corresponding to dummy shader upload. There is only one buffer_map(READ), in si_get_backend_mask, right after the buffer_map(WRITE) from si_get_backend_mask.