cifs: remove unnecessary locking of chan_lock while freeing session

In cifs_put_smb_ses, when we're freeing the last ref count to
the session, we need to free up each channel. At this point,
it is unnecessary to take chan_lock, since we have the last
reference to the ses.

Picking up this lock also introduced a deadlock because it calls
cifs_put_tcp_ses, which locks cifs_tcp_ses_lock.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Acked-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index fa29c9a..386bb52 100644 (file)
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -1918,7 +1918,6 @@ void cifs_put_smb_ses(struct cifs_ses *ses)
        list_del_init(&ses->smb_ses_list);
        spin_unlock(&cifs_tcp_ses_lock);
 
-       spin_lock(&ses->chan_lock);
        chan_count = ses->chan_count;
 
        /* close any extra channels */
@@ -1934,7 +1933,6 @@ void cifs_put_smb_ses(struct cifs_ses *ses)
                        ses->chans[i].server = NULL;
                }
        }
-       spin_unlock(&ses->chan_lock);
 
        sesInfoFree(ses);
        cifs_put_tcp_session(server, 0);