R4[04]00SC

We still have this stuff in flush_cache_mm():

       /*
         * Kludge alert.  For obscure reasons R4000SC and R4400SC go nuts if we
         * only flush the primary caches but R10000 and R12000 behave sane ...
         */
        if (current_cpu_data.cputype == CPU_R4000SC ||
            current_cpu_data.cputype == CPU_R4000MC ||
            current_cpu_data.cputype == CPU_R4400SC ||
            current_cpu_data.cputype == CPU_R4400MC)
                r4k_blast_scache();

You have any idea what might make this necessary? This slows down SC systems quite badly but makes the compiler from eleminating the call to r4k_blast_scache() on systems that don't have one of these processors.

Could be kludged a bit by also testing cpu_has_subset_pcaches() but that'd be a hack.

Ralf