[PATCH] mm: fix remap_pte_range BUG

Out-of-tree user of remap_pfn_range hit kernel BUG at mm/memory.c:1112!  It
passes an unrounded size to remap_pfn_range, which was okay before 2.6.12,
but misses remap_pte_range's new end condition.  An audit of all the other
ptwalks confirms that this is the only one so exposed.
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

mm/memory.c

@@ -1139,7 +1139,7 @@ int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr,
 {
 	pgd_t *pgd;
 	unsigned long next;
-	unsigned long end = addr + size;
+	unsigned long end = addr + PAGE_ALIGN(size);
 	struct mm_struct *mm = vma->vm_mm;
 	int err;