[PATCH 2/2] net/cxgb4: Don't retrieve stats during recovery

[Gavin Shan <shangw@linux.vnet.ibm.com>]

We possiblly retrieve the adapter's statistics during EEH recovery
and that should be disallowed. Otherwise, it would possibly incur
replicate EEH error and EEH recovery is going to fail eventually.
The patch checks if the PCI device is off-line before statistic
retrieval.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
---
 drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c |   11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
index c8eafbf..b0e72fb 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
@@ -4288,6 +4288,17 @@ static struct rtnl_link_stats64 *cxgb_get_stats(struct net_device *dev,
 	struct port_info *p = netdev_priv(dev);
 	struct adapter *adapter = p->adapter;
 
+	/*
+	 * We possibly retrieve the statistics while the PCI
+	 * device is off-line. That would cause the recovery
+	 * on off-lined PCI device going to fail. So it's
+	 * reasonable to block it during the recovery period.
+	 */
+	if (pci_channel_offline(adapter->pdev)) {
+		memset(ns, 0, sizeof(*ns));
+		return ns;
+	}
+
 	spin_lock(&adapter->stats_lock);
 	t4_get_port_stats(adapter, p->tx_chan, &stats);
 	spin_unlock(&adapter->stats_lock);
-- 
1.7.10.4