• Aneesh Kumar K.V's avatar
    powerpc/thp: Handle combo pages in invalidate · fc047955
    Aneesh Kumar K.V authored
    If we changed base page size of the segment, either via sub_page_protect
    or via remap_4k_pfn, we do a demote_segment which doesn't flush the hash
    table entries. We do a lazy hash page table flush for all mapped pages
    in the demoted segment. This happens when we handle hash page fault for
    these pages.
    
    We use _PAGE_COMBO bit along with _PAGE_HASHPTE to indicate whether a
    pte is backed by 4K hash pte. If we find _PAGE_COMBO not set on the pte,
    that implies that we could possibly have older 64K hash pte entries in
    the hash page table and we need to invalidate those entries.
    
    Use _PAGE_COMBO to determine the page size with which we should
    invalidate the hash table entries on unmap.
    
    CC: <stable@vger.kernel.org>
    Signed-off-by: default avatarAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
    Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
    fc047955
pgtable_64.c 22.6 KB