Commit 0bf598d8 authored Sep 11, 2013 by Naoya Horiguchi Committed by Linus Torvalds Sep 11, 2013

mbind: add BUG_ON(!vma) in new_vma_page()



new_vma_page() is called only by page migration called from do_mbind(),
where pages to be migrated are queued into a pagelist by
queue_pages_range().  queue_pages_range() confirms that a queued page
belongs to some vma, so !vma case is not supposed to be happen.  This
patch adds BUG_ON() to catch this unexpected case.

Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 98094945

mm/mempolicy.c

+5 −3

Original line number	Diff line number	Diff line
		@@ -1196,12 +1196,14 @@ static struct page new_vma_page(struct page page, unsigned long private, int *
		break;
		vma = vma->vm_next;
		}
		/*
		* queue_pages_range() confirms that @page belongs to some vma,
		* so vma shouldn't be NULL.
		*/
		BUG_ON(!vma);

		if (PageHuge(page))
		return alloc_huge_page_noerr(vma, address, 1);
		/*
		* if !vma, alloc_page_vma() will use task or system default policy
		*/
		return alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma, address);
		}
		#else