ext4: lock i_mutex when truncating orphan inodes
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 <a.beregalov@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
Cc: stable@vger.kernel.org
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 183ae34..3d4fb81 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -2220,7 +2220,9 @@
__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,
