net: xgene: fix backward compatibility fix
authorArnd Bergmann <arnd@arndb.de>
Mon, 29 Aug 2016 12:37:14 +0000 (14:37 +0200)
committerDavid S. Miller <davem@davemloft.net>
Thu, 1 Sep 2016 17:00:42 +0000 (10:00 -0700)
A bugfix for backward compatibility handling introduced undefined
behavior for the case that of_parse_phandle() does not return
a valid entry, as "gcc -Wmaybe-unused" reports:

drivers/net/ethernet/apm/xgene/xgene_enet_hw.c: In function 'xgene_enet_phy_connect':
drivers/net/ethernet/apm/xgene/xgene_enet_hw.c:776:6: error: 'phy_dev' may be used uninitialized in this function [-Werror=maybe-uninitialized]
drivers/net/ethernet/apm/xgene/xgene_enet_hw.c: In function 'xgene_enet_mdio_config':
drivers/net/ethernet/apm/xgene/xgene_enet_hw.c:776:6: error: 'phy_dev' may be used uninitialized in this function [-Werror=maybe-uninitialized]

We can work around this by removing the check for zero "np", as
of_phy_connect() will correctly handle a NULL argument so we fall
back into the normal error handling case.

Note that I had previously fixed another bug that resulted in the
exact same warning, but this is a different problem that was
introduced after my original fix.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 03377e381bf4 ("drivers: net: xgene: Fix backward compatibility")
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/ethernet/apm/xgene/xgene_enet_hw.c

index 321fb19..da413c8 100644 (file)
@@ -761,10 +761,6 @@ int xgene_enet_phy_connect(struct net_device *ndev)
        if (dev->of_node) {
                for (i = 0 ; i < 2; i++) {
                        np = of_parse_phandle(dev->of_node, "phy-handle", i);
-
-                       if (!np)
-                               continue;
-
                        phy_dev = of_phy_connect(ndev, np,
                                                 &xgene_enet_adjust_link,
                                                 0, pdata->phy_mode);