[PATCH 3.16 364/366] net: ethernet: davinci_emac: fix error handling in probe()

Ben Hutchings
2018-10-14T23:11:51Z

From: Dan Carpenter <dan.carpenter@oracle.com>

commit 8005b09d99fac78e6f5fb9da30b5ae94840af03b upstream.

The current error handling code has an issue where it does:

if (priv->txchan)
cpdma_chan_destroy(priv->txchan);

The problem is that ->txchan is either valid or an error pointer (which
would lead to an Oops). I've changed it to use multiple error labels so
that the test can be removed.

Also there were some missing calls to netif_napi_del().

Fixes: 3ef0fdb2342c ("net: davinci_emac: switch to new cpdma layer")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/net/ethernet/ti/davinci_emac.c | 22 ++++++++++++----------
1 file changed, 12 insertions(+), 10 deletions(-)

--- a/drivers/net/ethernet/ti/davinci_emac.c
+++ b/drivers/net/ethernet/ti/davinci_emac.c
@@ -1971,7 +1971,7 @@ static int davinci_emac_probe(struct pla
if (IS_ERR(priv->txchan)) {
dev_err(&pdev->dev, "error initializing tx dma channel\n");
rc = PTR_ERR(priv->txchan);
- goto no_cpdma_chan;
+ goto err_free_dma;
}

priv->rxchan = cpdma_chan_create(priv->dma, rx_chan_num(EMAC_DEF_RX_CH),
@@ -1979,14 +1979,14 @@ static int davinci_emac_probe(struct pla
if (IS_ERR(priv->rxchan)) {
dev_err(&pdev->dev, "error initializing rx dma channel\n");
rc = PTR_ERR(priv->rxchan);
- goto no_cpdma_chan;
+ goto err_free_txchan;
}

res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
if (!res) {
dev_err(&pdev->dev, "error getting irq res\n");
rc = -ENOENT;
- goto no_cpdma_chan;
+ goto err_free_rxchan;
}
ndev->irq = res->start;

@@ -2008,7 +2008,7 @@ static int davinci_emac_probe(struct pla
pm_runtime_put_noidle(&pdev->dev);
dev_err(&pdev->dev, "%s: failed to get_sync(%d)\n",
__func__, rc);
- goto no_cpdma_chan;
+ goto err_napi_del;
}

/* register the network device */
@@ -2018,7 +2018,7 @@ static int davinci_emac_probe(struct pla
dev_err(&pdev->dev, "error in register_netdev\n");
rc = -ENODEV;
pm_runtime_put(&pdev->dev);
- goto no_cpdma_chan;
+ goto err_napi_del;
}

@@ -2031,11 +2031,13 @@ static int davinci_emac_probe(struct pla

return 0;

-no_cpdma_chan:
- if (priv->txchan)
- cpdma_chan_destroy(priv->txchan);
- if (priv->rxchan)
- cpdma_chan_destroy(priv->rxchan);
+err_napi_del:
+ netif_napi_del(&priv->napi);
+err_free_rxchan:
+ cpdma_chan_destroy(priv->rxchan);
+err_free_txchan:
+ cpdma_chan_destroy(priv->txchan);
+err_free_dma:
cpdma_ctlr_destroy(priv->dma);
no_pdata:
free_netdev(ndev);