mm: numa: clear numa hinting information on mprotect

On a protection change it is no longer clear if the page should be still
accessible.  This patch clears the NUMA hinting fault bits on a
protection change.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index dbafffa5e2ee..70e7429fd8ea 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1532,6 +1532,8 @@ int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
                 ret = 1;
                 if (!prot_numa) {
                         entry = pmdp_get_and_clear(mm, addr, pmd);
+                        if (pmd_numa(entry))
+                                entry = pmd_mknonnuma(entry);
                         entry = pmd_modify(entry, newprot);
                         ret = HPAGE_PMD_NR;
                         BUG_ON(pmd_write(entry));