[PATCH 2/2] mm/mempolicy: Skip walking HUGETLB vma if MPOL_MF_STRICT is specified alone

[Li Xinhai <lixinhai.lxh@gmail.com>]

Checking MPOL_MF_STRICT is ignored for HUGETLB vma according to mbind man
page:

Notes
MPOL_MF_STRICT is ignored on huge page mappings.

If MPOL_MF_STRICT is specified alone without any MOVE flag, we should
indicate, from test_walk, that walking this vma should be skipped even if
there are misplaced pages.

Signed-off-by: Li Xinhai <lixinhai.lxh@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
---
 mm/mempolicy.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 067cf7d..c117b5f 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -656,6 +656,13 @@ static int queue_pages_test_walk(unsigned long start, unsigned long end,
 		return 1;
 	}
 
+	/* MPOL_MF_STRICT is ignored for huge page, skip checking
+	*  misplaced pages
+	*/
+	if ((flags & MPOL_MF_VALID) == MPOL_MF_STRICT &&
+		is_vm_hugetlb_page(vma))
+		return 1;
+
 	/* queue pages from current vma */
 	if (flags & MPOL_MF_VALID)
 		return 0;
-- 
1.8.3.1