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>
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index dbafffa..70e7429 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1532,6 +1532,8 @@
 		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));
diff --git a/mm/mprotect.c b/mm/mprotect.c
index 1291a05..f842172 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -54,6 +54,8 @@
 
 			if (!prot_numa) {
 				ptent = ptep_modify_prot_start(mm, addr, pte);
+				if (pte_numa(ptent))
+					ptent = pte_mknonnuma(ptent);
 				ptent = pte_modify(ptent, newprot);
 				updated = true;
 			} else {