IPoIB: Fix hang in napi_disable() if P_Key is never found

After commit fe25c561 ("IPoIB: Don't enable NAPI when it's already
enabled"), if an interface is brought up but the corresponding P_Key
never appears, then ipoib_stop() will hang in napi_disable(), because
ipoib_open() returns before it does napi_enable().

Fix this by changing ipoib_open() to call napi_enable() even if the
P_Key isn't present.

Reported-by: Yossi Etigin <yosefe@Voltaire.COM>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 15 insertions, 12 deletions

diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c b/drivers/infiniband/ulp/ipoib/ipoib_main.c
index dce0443f9d69..0bd2a4ff0842 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_main.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c
@@ -106,23 +106,17 @@ int ipoib_open(struct net_device *dev)
 
         ipoib_dbg(priv, "bringing up interface\n");
 
-        set_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags);
+        if (!test_and_set_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags))
+                napi_enable(&priv->napi);
 
         if (ipoib_pkey_dev_delay_open(dev))
                 return 0;
 
-        napi_enable(&priv->napi);
+        if (ipoib_ib_dev_open(dev))
+                goto err_disable;
 
-        if (ipoib_ib_dev_open(dev)) {
-                napi_disable(&priv->napi);
-                return -EINVAL;
-        }
-
-        if (ipoib_ib_dev_up(dev)) {
-                ipoib_ib_dev_stop(dev, 1);
-                napi_disable(&priv->napi);
-                return -EINVAL;
-        }
+        if (ipoib_ib_dev_up(dev))
+                goto err_stop;
 
         if (!test_bit(IPOIB_FLAG_SUBINTERFACE, &priv->flags)) {
                 struct ipoib_dev_priv *cpriv;
@@ -144,6 +138,15 @@ int ipoib_open(struct net_device *dev)
         netif_start_queue(dev);
 
         return 0;
+
+err_stop:
+        ipoib_ib_dev_stop(dev, 1);
+
+err_disable:
+        napi_disable(&priv->napi);
+        clear_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags);
+
+        return -EINVAL;
 }
 
 static int ipoib_stop(struct net_device *dev)