net: hibmcge: fix wrong ndo.open() after reset fail issue.

If the driver reset fails, it may not work properly.
Therefore, the ndo.open() operation should be rejected.

In this patch, the driver calls netif_device_detach()
before the reset and calls netif_device_attach()
after the reset succeeds. If the reset fails,
netif_device_attach() is not called. Therefore,
netdev does not present and cannot be opened.

If reset fails, only the PCI reset (via sysfs)
can be used to attempt recovery.

Fixes: 3f5a61f ("net: hibmcge: Add reset supported in this module")
Signed-off-by: Jijie Shao <[email protected]>
Reviewed-by: Simon Horman <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

Author: Jijie Shao

drivers/net/ethernet/hisilicon/hibmcge/hbg_err.c

@@ -61,6 +61,8 @@ static int hbg_reset_prepare(struct hbg_priv *priv, enum hbg_reset_type type)
 		return -EBUSY;
 	}
 
+	netif_device_detach(priv->netdev);
+
 	priv->reset_type = type;
 	set_bit(HBG_NIC_STATE_RESETTING, &priv->state);
 	clear_bit(HBG_NIC_STATE_RESET_FAIL, &priv->state);
@@ -91,6 +93,8 @@ static int hbg_reset_done(struct hbg_priv *priv, enum hbg_reset_type type)
 		return ret;
 	}
 
+	netif_device_attach(priv->netdev);
+
 	dev_info(&priv->pdev->dev, "reset done\n");
 	return ret;
 }
@@ -117,16 +121,13 @@ void hbg_err_reset(struct hbg_priv *priv)
 	if (running)
 		dev_close(priv->netdev);
 
-	hbg_reset(priv);
-
-	/* in hbg_pci_err_detected(), we will detach first,
-	 * so we need to attach before open
-	 */
-	if (!netif_device_present(priv->netdev))
-		netif_device_attach(priv->netdev);
+	if (hbg_reset(priv))
+		goto err_unlock;
 
 	if (running)
 		dev_open(priv->netdev, NULL);
+
+err_unlock:
 	rtnl_unlock();
 }
 
@@ -160,7 +161,6 @@ static pci_ers_result_t hbg_pci_err_slot_reset(struct pci_dev *pdev)
 	pci_save_state(pdev);
 
 	hbg_err_reset(priv);
-	netif_device_attach(netdev);
 	return PCI_ERS_RESULT_RECOVERED;
 }