From 3a05d9a7eece69d2c53a37dd308f2b4c20dd2751 Mon Sep 17 00:00:00 2001
From: Wu Fengguang <fengguang.wu@intel.com>
Date: Wed, 16 Sep 2009 11:50:14 +0200
Subject: [PATCH] --- yaml --- r: 165735 b: refs/heads/master c:
 6746aff74da293b5fd24e5c68b870b721e86cd5f h: refs/heads/master i:   165733:
 04fd0f3cd8b97ffd61f9f771dc0bde104c5eacad   165731:
 9ba918f29b7b19671be536bf64e2a35a8c85be48   165727:
 6dde4fd95a01b11bf23377287c482d529bb2cab6 v: v3

---
 [refs]                    | 2 +-
 trunk/mm/page-writeback.c | 7 +++++++
 trunk/mm/shmem.c          | 4 ++--
 3 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/[refs] b/[refs]
index 3ac4167991aa..9d83b5e9e749 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 257187362123f15d9d1e09918cf87cebbea4e786
+refs/heads/master: 6746aff74da293b5fd24e5c68b870b721e86cd5f
diff --git a/trunk/mm/page-writeback.c b/trunk/mm/page-writeback.c
index dd73d29c15a8..bba82c414ba8 100644
--- a/trunk/mm/page-writeback.c
+++ b/trunk/mm/page-writeback.c
@@ -1149,6 +1149,13 @@ int redirty_page_for_writepage(struct writeback_control *wbc, struct page *page)
 EXPORT_SYMBOL(redirty_page_for_writepage);
 
 /*
+ * Dirty a page.
+ *
+ * For pages with a mapping this should be done under the page lock
+ * for the benefit of asynchronous memory errors who prefer a consistent
+ * dirty state. This rule can be broken in some special cases,
+ * but should be better not to.
+ *
  * If the mapping doesn't provide a set_page_dirty a_op, then
  * just fall through and assume that it wants buffer_heads.
  */
diff --git a/trunk/mm/shmem.c b/trunk/mm/shmem.c
index 5a0b3d4055f3..46936601e37f 100644
--- a/trunk/mm/shmem.c
+++ b/trunk/mm/shmem.c
@@ -1630,8 +1630,8 @@ shmem_write_end(struct file *file, struct address_space *mapping,
 	if (pos + copied > inode->i_size)
 		i_size_write(inode, pos + copied);
 
-	unlock_page(page);
 	set_page_dirty(page);
+	unlock_page(page);
 	page_cache_release(page);
 
 	return copied;
@@ -1968,13 +1968,13 @@ static int shmem_symlink(struct inode *dir, struct dentry *dentry, const char *s
 			iput(inode);
 			return error;
 		}
-		unlock_page(page);
 		inode->i_mapping->a_ops = &shmem_aops;
 		inode->i_op = &shmem_symlink_inode_operations;
 		kaddr = kmap_atomic(page, KM_USER0);
 		memcpy(kaddr, symname, len);
 		kunmap_atomic(kaddr, KM_USER0);
 		set_page_dirty(page);
+		unlock_page(page);
 		page_cache_release(page);
 	}
 	if (dir->i_mode & S_ISGID)