[PATCH] Page migration: Fix vma flag checking

Currently we do not check for vma flags if sys_move_pages is called to move
individual pages.  If sys_migrate_pages is called to move pages then we
check for vm_flags that indicate a non migratable vma but that still
includes VM_LOCKED and we can migrate mlocked pages.

Extract the vma_migratable check from mm/mempolicy.c, fix it and put it
into migrate.h so that is can be used from both locations.

Problem was spotted by Lee Schermerhorn

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 0 insertions, 9 deletions

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index cf2a5381030a..d76e8eb342d0 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -321,15 +321,6 @@ static inline int check_pgd_range(struct vm_area_struct *vma,
         return 0;
 }
 
-/* Check if a vma is migratable */
-static inline int vma_migratable(struct vm_area_struct *vma)
-{
-        if (vma->vm_flags & (
-                VM_LOCKED|VM_IO|VM_HUGETLB|VM_PFNMAP|VM_RESERVED))
-                return 0;
-        return 1;
-}
-
 /*
  * Check if all pages in a range are on a set of nodes.
  * If pagelist != NULL then isolate pages from the LRU and