mm/hwpoison: fix fail isolate hugetlbfs page w/ refcount held

Hugetlbfs pages will get a refcount in get_any_page() or madvise_hwpoison() if soft offlining through madvise. The refcount which is held by the soft offline path should be released if we fail to isolate hugetlbfs pages. Fix it by reducing the refcount for both isolation success and failure. Signed-off-by: Wanpeng Li <[email protected]> Acked-by: Naoya Horiguchi <[email protected]> Cc: <[email protected]> [3.9+] Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
fracktal · Aug 14, 2015 · 0361380 · 0361380
1 parent 4f32be6
commit 0361380
Showing 1 changed file with 6 additions and 7 deletions.
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
@@ -1569,13 +1569,12 @@ static int soft_offline_huge_page(struct page *page, int flags)
 	unlock_page(hpage);
 
 	ret = isolate_huge_page(hpage, &pagelist);
-	if (ret) {
-		/*
-		 * get_any_page() and isolate_huge_page() takes a refcount each,
-		 * so need to drop one here.
-		 */
-		put_page(hpage);
-	} else {
+	/*
+	 * get_any_page() and isolate_huge_page() takes a refcount each,
+	 * so need to drop one here.
+	 */
+	put_page(hpage);
+	if (!ret) {
 		pr_info("soft offline: %#lx hugepage failed to isolate\n", pfn);
 		return -EBUSY;
 	}