Altera TSE: Fix Panic in probe routine when phy probe fails

This patch addresses a fault in the error recovery path of the probe
routine where the netdev structure was not being unregistered properly
leading to a panic only when the phy probe failed.

Abbreviated panic stack seen is as follows:

(free_netdev+0xXX) from (altera_tse_probe+0xXX)
(altera_tse_probe+0xXX) from (platform_drv_probe+0xXX)
(platform_drv_probe+0xXX) from (driver_probe_device+0xXX)
(driver_probe_device+0xXX) from (__driver_attach+0xXX)
(__driver_attach+0xXX) from (bus_for_each_dev+0xXX)
(bus_for_each_dev+0xXX) from (driver_attach+0xXX)
(driver_attach+0xXX) from (bus_add_driver+0xXX)
(bus_add_driver+0xXX) from (driver_register+0xXX)
(driver_register+0xXX) from (__platform_driver_register+0xXX)
(__platform_driver_register+0xXX) from (altera_tse_driver_init+0xXX)
(altera_tse_driver_init+0xXX) from (do_one_initcall+0xXX)
(do_one_initcall+0xXX) from (kernel_init_freeable+0xXX)
(kernel_init_freeable+0xXX) from (kernel_init+0xXX)
(kernel_init+0xXX) from (ret_from_fork+0xXX)

Signed-off-by: Vince Bridgers <vbridgers2013@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 24 insertions, 21 deletions

diff --git a/drivers/net/ethernet/altera/altera_tse_main.c b/drivers/net/ethernet/altera/altera_tse_main.c
index 63712830b333..e44a4aeb9701 100644
--- a/drivers/net/ethernet/altera/altera_tse_main.c
+++ b/drivers/net/ethernet/altera/altera_tse_main.c
@@ -1245,7 +1245,7 @@ static int altera_tse_probe(struct platform_device *pdev)
                 /* Get the mapped address to the SGDMA descriptor memory */
                 ret = request_and_map(pdev, "s1", &dma_res, &descmap);
                 if (ret)
-                        goto out_free;
+                        goto err_free_netdev;
 
                 /* Start of that memory is for transmit descriptors */
                 priv->tx_dma_desc = descmap;
@@ -1264,24 +1264,24 @@ static int altera_tse_probe(struct platform_device *pdev)
                 if (upper_32_bits(priv->rxdescmem_busaddr)) {
                         dev_dbg(priv->device,
                                 "SGDMA bus addresses greater than 32-bits\n");
-                        goto out_free;
+                        goto err_free_netdev;
                 }
                 if (upper_32_bits(priv->txdescmem_busaddr)) {
                         dev_dbg(priv->device,
                                 "SGDMA bus addresses greater than 32-bits\n");
-                        goto out_free;
+                        goto err_free_netdev;
                 }
         } else if (priv->dmaops &&
                    priv->dmaops->altera_dtype == ALTERA_DTYPE_MSGDMA) {
                 ret = request_and_map(pdev, "rx_resp", &dma_res,
                                       &priv->rx_dma_resp);
                 if (ret)
-                        goto out_free;
+                        goto err_free_netdev;
 
                 ret = request_and_map(pdev, "tx_desc", &dma_res,
                                       &priv->tx_dma_desc);
                 if (ret)
-                        goto out_free;
+                        goto err_free_netdev;
 
                 priv->txdescmem = resource_size(dma_res);
                 priv->txdescmem_busaddr = dma_res->start;
@@ -1289,13 +1289,13 @@ static int altera_tse_probe(struct platform_device *pdev)
                 ret = request_and_map(pdev, "rx_desc", &dma_res,
                                       &priv->rx_dma_desc);
                 if (ret)
-                        goto out_free;
+                        goto err_free_netdev;
 
                 priv->rxdescmem = resource_size(dma_res);
                 priv->rxdescmem_busaddr = dma_res->start;
 
         } else {
-                goto out_free;
+                goto err_free_netdev;
         }
 
         if (!dma_set_mask(priv->device, DMA_BIT_MASK(priv->dmaops->dmamask)))
@@ -1304,26 +1304,26 @@ static int altera_tse_probe(struct platform_device *pdev)
         else if (!dma_set_mask(priv->device, DMA_BIT_MASK(32)))
                 dma_set_coherent_mask(priv->device, DMA_BIT_MASK(32));
         else
-                goto out_free;
+                goto err_free_netdev;
 
         /* MAC address space */
         ret = request_and_map(pdev, "control_port", &control_port,
                               (void __iomem **)&priv->mac_dev);
         if (ret)
-                goto out_free;
+                goto err_free_netdev;
 
         /* xSGDMA Rx Dispatcher address space */
         ret = request_and_map(pdev, "rx_csr", &dma_res,
                               &priv->rx_dma_csr);
         if (ret)
-                goto out_free;
+                goto err_free_netdev;
 
 
         /* xSGDMA Tx Dispatcher address space */
         ret = request_and_map(pdev, "tx_csr", &dma_res,
                               &priv->tx_dma_csr);
         if (ret)
-                goto out_free;
+                goto err_free_netdev;
 
 
         /* Rx IRQ */
@@ -1331,7 +1331,7 @@ static int altera_tse_probe(struct platform_device *pdev)
         if (priv->rx_irq == -ENXIO) {
                 dev_err(&pdev->dev, "cannot obtain Rx IRQ\n");
                 ret = -ENXIO;
-                goto out_free;
+                goto err_free_netdev;
         }
 
         /* Tx IRQ */
@@ -1339,7 +1339,7 @@ static int altera_tse_probe(struct platform_device *pdev)
         if (priv->tx_irq == -ENXIO) {
                 dev_err(&pdev->dev, "cannot obtain Tx IRQ\n");
                 ret = -ENXIO;
-                goto out_free;
+                goto err_free_netdev;
         }
 
         /* get FIFO depths from device tree */
@@ -1347,14 +1347,14 @@ static int altera_tse_probe(struct platform_device *pdev)
                                  &priv->rx_fifo_depth)) {
                 dev_err(&pdev->dev, "cannot obtain rx-fifo-depth\n");
                 ret = -ENXIO;
-                goto out_free;
+                goto err_free_netdev;
         }
 
         if (of_property_read_u32(pdev->dev.of_node, "tx-fifo-depth",
                                  &priv->rx_fifo_depth)) {
                 dev_err(&pdev->dev, "cannot obtain tx-fifo-depth\n");
                 ret = -ENXIO;
-                goto out_free;
+                goto err_free_netdev;
         }
 
         /* get hash filter settings for this instance */
@@ -1403,7 +1403,7 @@ static int altera_tse_probe(struct platform_device *pdev)
               ((priv->phy_addr >= 0) && (priv->phy_addr < PHY_MAX_ADDR)))) {
                 dev_err(&pdev->dev, "invalid phy-addr specified %d\n",
                         priv->phy_addr);
-                goto out_free;
+                goto err_free_netdev;
         }
 
         /* Create/attach to MDIO bus */
@@ -1411,7 +1411,7 @@ static int altera_tse_probe(struct platform_device *pdev)
                                      atomic_add_return(1, &instance_count));
 
         if (ret)
-                goto out_free;
+                goto err_free_netdev;
 
         /* initialize netdev */
         ether_setup(ndev);
@@ -1448,7 +1448,7 @@ static int altera_tse_probe(struct platform_device *pdev)
         ret = register_netdev(ndev);
         if (ret) {
                 dev_err(&pdev->dev, "failed to register TSE net device\n");
-                goto out_free_mdio;
+                goto err_register_netdev;
         }
 
         platform_set_drvdata(pdev, ndev);
@@ -1465,13 +1465,16 @@ static int altera_tse_probe(struct platform_device *pdev)
         ret = init_phy(ndev);
         if (ret != 0) {
                 netdev_err(ndev, "Cannot attach to PHY (error: %d)\n", ret);
-                goto out_free_mdio;
+                goto err_init_phy;
         }
         return 0;
 
-out_free_mdio:
+err_init_phy:
+        unregister_netdev(ndev);
+err_register_netdev:
+        netif_napi_del(&priv->napi);
         altera_tse_mdio_destroy(ndev);
-out_free:
+err_free_netdev:
         free_netdev(ndev);
         return ret;
 }