diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h index fe57e7a98839..2562e303405b 100644 --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -398,11 +398,17 @@ static inline int is_new_memtype_allowed(u64 paddr, unsigned long size, * requested memtype: * - request is uncached, return cannot be write-back * - request is write-combine, return cannot be write-back + * - request is write-through, return cannot be write-back + * - request is write-through, return cannot be write-combine */ if ((pcm == _PAGE_CACHE_MODE_UC_MINUS && new_pcm == _PAGE_CACHE_MODE_WB) || (pcm == _PAGE_CACHE_MODE_WC && - new_pcm == _PAGE_CACHE_MODE_WB)) { + new_pcm == _PAGE_CACHE_MODE_WB) || + (pcm == _PAGE_CACHE_MODE_WT && + new_pcm == _PAGE_CACHE_MODE_WB) || + (pcm == _PAGE_CACHE_MODE_WT && + new_pcm == _PAGE_CACHE_MODE_WC)) { return 0; }