The current MIPS 2.4 kernel (from CVS) currently allows fixed shared mappings to violate D-cache aliasing constraints. The check for illegal fixed mappings is done in arch_get_unmapped_area(), but these mappings are granted in get_unmapped_area() and arch_get_unmapped_area() is never called. A quick look at sparc and sparc64 seem to show the same problem. P.
