Merge tag 'v3.10.37' of git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable into linux-lnglinux-lng-v3.10.37-finallinux-lng-v3.10.xlinux-lng

This is the 3.10.37 stable release

Conflicts:
	scripts/package/builddeb

1 files changed, 12 insertions, 2 deletions

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 3bf21c3502d0..a9a48309f045 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -361,8 +361,18 @@ static inline void compound_unlock_irqrestore(struct page *page,
 
 static inline struct page *compound_head(struct page *page)
 {
-	if (unlikely(PageTail(page)))
-		return page->first_page;
+	if (unlikely(PageTail(page))) {
+		struct page *head = page->first_page;
+
+		/*
+		 * page->first_page may be a dangling pointer to an old
+		 * compound page, so recheck that it is still a tail
+		 * page before returning.
+		 */
+		smp_rmb();
+		if (likely(PageTail(page)))
+			return head;
+	}
 	return page;
 }