From: Akira Fujita <a-fujita@rs.jp.nec.com>
Date: Thu, 20 Oct 2011 22:56:10 +0000 (-0400)
Subject: ext4: fix deadlock in ext4_ordered_write_end()
X-Git-Tag: next-20111101~64^2~37
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=09e0834fb0ce1ea2a63885177015bd5d7d2bc22d;p=karo-tx-linux.git

ext4: fix deadlock in ext4_ordered_write_end()

If ext4_jbd2_file_inode() in ext4_ordered_write_end() fails for some
reasons, this function returns to caller without unlocking the page.
It leads to the deadlock, and the patch fixes this issue.

Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
---

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 081bb25a9ad3..ecb572591924 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -959,7 +959,11 @@ static int ext4_ordered_write_end(struct file *file,
 			ext4_orphan_add(handle, inode);
 		if (ret2 < 0)
 			ret = ret2;
+	} else {
+		unlock_page(page);
+		page_cache_release(page);
 	}
+
 	ret2 = ext4_journal_stop(handle);
 	if (!ret)
 		ret = ret2;