[PATCH v1] stmmac: intel: Fix kernel crash due to wrong error path

[Andy Shevchenko]

Unfortunately sometimes ->probe() may fail. The commit b9663b7ca6ff
("net: stmmac: Enable SERDES power up/down sequence")
messed up with error handling and thus:

[   12.811311] ------------[ cut here ]------------
[   12.811993] kernel BUG at net/core/dev.c:9937!

Fix this by properly crafted error path.

Fixes: b9663b7ca6ff ("net: stmmac: Enable SERDES power up/down sequence")
Cc: Voon Weifeng <weifeng.v...@intel.com>
Cc: Ong Boon Leong <boon.leong....@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevche...@linux.intel.com>
---
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c 
b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 565da6498c846e..ff22f274aa43d6 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -4991,7 +4991,7 @@ int stmmac_dvr_probe(struct device *device,
                                                 priv->plat->bsp_priv);
 
                if (ret < 0)
-                       return ret;
+                       goto error_serdes_powerup;
        }
 
 #ifdef CONFIG_DEBUG_FS
@@ -5000,6 +5000,8 @@ int stmmac_dvr_probe(struct device *device,
 
        return ret;
 
+error_serdes_powerup:
+       unregister_netdev(ndev);
 error_netdev_register:
        phylink_destroy(priv->phylink);
 error_phy_setup:
-- 
2.26.2