[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: Hugh Dickins <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

mm/memory.c

···
 {
 	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;