[PATCH rdma-next] IB/ipoib: Add child to parent list only if device initialized

[Leon Romanovsky <leon@xxxxxxxxxx>]

From: Valentine Fatiev <valentinef@xxxxxxxxxxxx>

Despite failure in ipoib_dev_init() we continue with initialization
flow and creation of child device. It causes to the situation
where this child device is added too early to parent device list.

change the logic, so in case of failure we properly return error
from ipoib_dev_init() and add child only in success path.

Fixes: eaeb39842508 ("IB/ipoib: Move init code to ndo_init")
Signed-off-by: Valentine Fatiev <valentinef@xxxxxxxxxxxx>
Reviewed-by: Feras Daoud <ferasda@xxxxxxxxxxxx>
Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxxxx>
---
 drivers/infiniband/ulp/ipoib/ipoib_main.c | 34 +++++++++++++----------
 1 file changed, 20 insertions(+), 14 deletions(-)

diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c b/drivers/infiniband/ulp/ipoib/ipoib_main.c
index 9b5e11d3fb85..bb904ec511be 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_main.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c
@@ -1893,12 +1893,6 @@ static void ipoib_child_init(struct net_device *ndev)
 	struct ipoib_dev_priv *priv = ipoib_priv(ndev);
 	struct ipoib_dev_priv *ppriv = ipoib_priv(priv->parent);
 
-	dev_hold(priv->parent);
-
-	down_write(&ppriv->vlan_rwsem);
-	list_add_tail(&priv->list, &ppriv->child_intfs);
-	up_write(&ppriv->vlan_rwsem);
-
 	priv->max_ib_mtu = ppriv->max_ib_mtu;
 	set_bit(IPOIB_FLAG_SUBINTERFACE, &priv->flags);
 	memcpy(priv->dev->dev_addr, ppriv->dev->dev_addr, INFINIBAND_ALEN);
@@ -1941,6 +1935,17 @@ static int ipoib_ndo_init(struct net_device *ndev)
 	if (rc) {
 		pr_warn("%s: failed to initialize device: %s port %d (ret = %d)\n",
 			priv->ca->name, priv->dev->name, priv->port, rc);
+		return rc;
+	}
+
+	if (priv->parent) {
+		struct ipoib_dev_priv *ppriv = ipoib_priv(priv->parent);
+
+		dev_hold(priv->parent);
+
+		down_write(&ppriv->vlan_rwsem);
+		list_add_tail(&priv->list, &ppriv->child_intfs);
+		up_write(&ppriv->vlan_rwsem);
 	}
 
 	return 0;
@@ -1958,6 +1963,14 @@ static void ipoib_ndo_uninit(struct net_device *dev)
 	 */
 	WARN_ON(!list_empty(&priv->child_intfs));
 
+	if (priv->parent) {
+		struct ipoib_dev_priv *ppriv = ipoib_priv(priv->parent);
+
+		down_write(&ppriv->vlan_rwsem);
+		list_del(&priv->list);
+		up_write(&ppriv->vlan_rwsem);
+	}
+
 	ipoib_neigh_hash_uninit(dev);
 
 	ipoib_ib_dev_cleanup(dev);
@@ -1969,15 +1982,8 @@ static void ipoib_ndo_uninit(struct net_device *dev)
 		priv->wq = NULL;
 	}
 
-	if (priv->parent) {
-		struct ipoib_dev_priv *ppriv = ipoib_priv(priv->parent);
-
-		down_write(&ppriv->vlan_rwsem);
-		list_del(&priv->list);
-		up_write(&ppriv->vlan_rwsem);
-
+	if (priv->parent)
 		dev_put(priv->parent);
-	}
 }
 
 static int ipoib_set_vf_link_state(struct net_device *dev, int vf, int link_state)
-- 
2.20.1