MD_APG_KUAP
mtspr(SPRN_MD_AP, MD_APG_KUAP);
WARN_ON_ONCE(mfspr(SPRN_MD_AP) >> 16 != MD_APG_KUAP >> 16);
"i"(SPRN_MD_AP), "r"(MD_APG_KUAP), "i"(MMU_FTR_KUAP) : "memory");
return !((regs->kuap ^ MD_APG_KUAP) & 0xff000000);