1 files changed, 20 insertions, 9 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 542fc088ff50..fc241fe295ab 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -225,7 +225,7 @@ static void bad_page(struct page *page)
 
 static void free_compound_page(struct page *page)
 {
-        __free_pages_ok(page, (unsigned long)page[1].lru.prev);
+        __free_pages_ok(page, compound_order(page));
 }
 
 static void prep_compound_page(struct page *page, unsigned long order)
@@ -234,12 +234,14 @@ static void prep_compound_page(struct page *page, unsigned long order)
         int nr_pages = 1 << order;
 
         set_compound_page_dtor(page, free_compound_page);
-        page[1].lru.prev = (void *)order;
-        for (i = 0; i < nr_pages; i++) {
+        set_compound_order(page, order);
+        __SetPageCompound(page);
+        for (i = 1; i < nr_pages; i++) {
                 struct page *p = page + i;
 
+                __SetPageTail(p);
                 __SetPageCompound(p);
-                set_page_private(p, (unsigned long)page);
+                p->first_page = page;
         }
 }
 
@@ -248,15 +250,19 @@ static void destroy_compound_page(struct page *page, unsigned long order)
         int i;
         int nr_pages = 1 << order;
 
-        if (unlikely((unsigned long)page[1].lru.prev != order))
+        if (unlikely(compound_order(page) != order))
                 bad_page(page);
 
-        for (i = 0; i < nr_pages; i++) {
+        if (unlikely(!PageCompound(page)))
+                        bad_page(page);
+        __ClearPageCompound(page);
+        for (i = 1; i < nr_pages; i++) {
                 struct page *p = page + i;
 
-                if (unlikely(!PageCompound(p) |
-                                (page_private(p) != (unsigned long)page)))
+                if (unlikely(!PageCompound(p) | !PageTail(p) |
+                                (p->first_page != page)))
                         bad_page(page);
+                __ClearPageTail(p);
                 __ClearPageCompound(p);
         }
 }
@@ -429,13 +435,18 @@ static inline int free_pages_check(struct page *page)
                         1 << PG_private |
                         1 << PG_locked  |
                         1 << PG_active  |
-                        1 << PG_reclaim |
                         1 << PG_slab    |
                         1 << PG_swapcache |
                         1 << PG_writeback |
                         1 << PG_reserved |
                         1 << PG_buddy ))))
                 bad_page(page);
+        /*
+         * PageReclaim == PageTail. It is only an error
+         * for PageReclaim to be set if PageCompound is clear.
+         */
+        if (unlikely(!PageCompound(page) && PageReclaim(page)))
+                bad_page(page);
         if (PageDirty(page))
                 __ClearPageDirty(page);
         /*