From: Theodore Ts'o Date: Thu, 27 Dec 2012 06:42:48 +0000 (-0500) Subject: ext4: lock i_mutex when truncating orphan inodes X-Git-Tag: v2.6.34.15~36 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0fd8d8773fd8c2a136efbc0f0e705e51ee181be9;p=thirdparty%2Fkernel%2Fstable.git ext4: lock i_mutex when truncating orphan inodes commit 721e3eba21e43532e438652dd8f1fcdfce3187e7 upstream. Commit c278531d39 added a warning when ext4_flush_unwritten_io() is called without i_mutex being taken. It had previously not been taken during orphan cleanup since races weren't possible at that point in the mount process, but as a result of this c278531d39, we will now see a kernel WARN_ON in this case. Take the i_mutex in ext4_orphan_cleanup() to suppress this warning. Reported-by: Alexander Beregalov Signed-off-by: "Theodore Ts'o" Reviewed-by: Zheng Liu Signed-off-by: Paul Gortmaker --- diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 6928d5ad2c0d3..90906948e242e 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -2028,7 +2028,9 @@ static void ext4_orphan_cleanup(struct super_block *sb, __func__, inode->i_ino, inode->i_size); jbd_debug(2, "truncating inode %lu to %lld bytes\n", inode->i_ino, inode->i_size); + mutex_lock(&inode->i_mutex); ext4_truncate(inode); + mutex_unlock(&inode->i_mutex); nr_truncates++; } else { ext4_msg(sb, KERN_DEBUG,