IB/cm: Fix stale connection detection

The ib_cm can incorrectly detect a stale connection (a new connection
request for a QPN that is already connected) as a duplicate connection
request.  Separate the handling of potential duplicate REQs from stale
connections.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

diff --git a/drivers/infiniband/core/cm.c b/drivers/infiniband/core/cm.c
index e840434..40c004a 100644 (file)
--- a/drivers/infiniband/core/cm.c
+++ b/drivers/infiniband/core/cm.c
@@ -1297,26 +1297,29 @@ static struct cm_id_private * cm_match_req(struct cm_work *work,
 
        req_msg = (struct cm_req_msg *)work->mad_recv_wc->recv_buf.mad;
 
-       /* Check for duplicate REQ and stale connections. */
+       /* Check for possible duplicate REQ. */
        spin_lock_irqsave(&cm.lock, flags);
        timewait_info = cm_insert_remote_id(cm_id_priv->timewait_info);
-       if (!timewait_info)
-               timewait_info = cm_insert_remote_qpn(cm_id_priv->timewait_info);
-
        if (timewait_info) {
                cur_cm_id_priv = cm_get_id(timewait_info->work.local_id,
                                           timewait_info->work.remote_id);
-               cm_cleanup_timewait(cm_id_priv->timewait_info);
                spin_unlock_irqrestore(&cm.lock, flags);
                if (cur_cm_id_priv) {
                        cm_dup_req_handler(work, cur_cm_id_priv);
                        cm_deref_id(cur_cm_id_priv);
-               } else
-                       cm_issue_rej(work->port, work->mad_recv_wc,
-                                    IB_CM_REJ_STALE_CONN, CM_MSG_RESPONSE_REQ,
-                                    NULL, 0);
-               listen_cm_id_priv = NULL;
-               goto out;
+               }
+               return NULL;
+       }
+
+       /* Check for stale connections. */
+       timewait_info = cm_insert_remote_qpn(cm_id_priv->timewait_info);
+       if (timewait_info) {
+               cm_cleanup_timewait(cm_id_priv->timewait_info);
+               spin_unlock_irqrestore(&cm.lock, flags);
+               cm_issue_rej(work->port, work->mad_recv_wc,
+                            IB_CM_REJ_STALE_CONN, CM_MSG_RESPONSE_REQ,
+                            NULL, 0);
+               return NULL;
        }
 
        /* Find matching listen request. */