--- 5d7601b0287487321314c1d969f17425b339f9b1
+++ f5a106eeb2bd532c258c0b0d83c422de17a7b924
@@ -401,7 +401,7 @@ static void clear_huge_page(struct page
 {
 	int i;
 
-	if (unlikely(sz > MAX_ORDER_NR_PAGES)) {
+	if (unlikely(sz/PAGE_SIZE > MAX_ORDER_NR_PAGES)) {
 		clear_gigantic_page(page, addr, sz);
 		return;
 	}
@@ -545,6 +545,7 @@ static void free_huge_page(struct page *
 
 	mapping = (struct address_space *) page_private(page);
 	set_page_private(page, 0);
+	page->mapping = NULL;
 	BUG_ON(page_count(page));
 	INIT_LIST_HEAD(&page->lru);
 
@@ -1007,7 +1008,7 @@ static struct page *alloc_huge_page(stru
 		page = alloc_buddy_huge_page(h, vma, addr);
 		if (!page) {
 			hugetlb_put_quota(inode->i_mapping, chg);
-			return ERR_PTR(-VM_FAULT_OOM);
+			return ERR_PTR(-VM_FAULT_SIGBUS);
 		}
 	}
 
@@ -2095,8 +2096,10 @@ retry:
 			spin_lock(&inode->i_lock);
 			inode->i_blocks += blocks_per_huge_page(h);
 			spin_unlock(&inode->i_lock);
-		} else
+		} else {
 			lock_page(page);
+			page->mapping = HUGETLB_POISON;
+		}
 	}
 
 	/*