IB/ipoib: Set IPOIB_NEIGH_TBL_FLUSH after flushed completion initialization

Set IPOIB_NEIGH_TBL_FLUSH bit after initializing the neighbor
flushed completion, otherwise the garbage collector may signal
a completion while it is not initialized yet.

Fixes: b63b70d8 ("IPoIB: Use a private hash table for path lookup in xmit path")
Signed-off-by: NFeras Daoud <ferasda@mellanox.com>
Signed-off-by: NAlex Vesker <valex@mellanox.com>
Signed-off-by: NLeon Romanovsky <leon@kernel.org>

drivers/infiniband/ulp/ipoib/ipoib_main.c

@@ -1560,6 +1560,7 @@ static void ipoib_flush_neighs(struct ipoib_dev_priv *priv)
 	int i, wait_flushed = 0;
 
 	init_completion(&priv->ntbl.flushed);
+	set_bit(IPOIB_NEIGH_TBL_FLUSH, &priv->flags);
 
 	spin_lock_irqsave(&priv->lock, flags);
 
@@ -1604,7 +1605,6 @@ static void ipoib_neigh_hash_uninit(struct net_device *dev)
 
 	ipoib_dbg(priv, "ipoib_neigh_hash_uninit\n");
 	init_completion(&priv->ntbl.deleted);
-	set_bit(IPOIB_NEIGH_TBL_FLUSH, &priv->flags);
 
 	/* Stop GC if called at init fail need to cancel work */
 	stopped = test_and_set_bit(IPOIB_STOP_NEIGH_GC, &priv->flags);