NET: fec: only enable napi if we are successful

If napi is left enabled after a failed attempt to bring the interface
up, we BUG:

fec 2188000.ethernet eth0: no PHY, assuming direct connection to switch
libphy: PHY fixed-0:00 not found
fec 2188000.ethernet eth0: could not attach to PHY
------------[ cut here ]------------
kernel BUG at include/linux/netdevice.h:502!
Internal error: Oops - BUG: 0 [#1] SMP ARM
...
PC is at fec_enet_open+0x4d0/0x500
LR is at __dev_open+0xa4/0xfc

Only enable napi after we are past all the failure paths.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index d4782b4..903362a 100644 (file)
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -1778,8 +1778,6 @@ fec_enet_open(struct net_device *ndev)
        struct fec_enet_private *fep = netdev_priv(ndev);
        int ret;
 
-       napi_enable(&fep->napi);
-
        /* I should reset the ring buffers here, but I don't yet know
         * a simple way to do that.
         */
@@ -1794,6 +1792,8 @@ fec_enet_open(struct net_device *ndev)
                fec_enet_free_buffers(ndev);
                return ret;
        }
+
+       napi_enable(&fep->napi);
        phy_start(fep->phy_dev);
        netif_start_queue(ndev);
        fep->opened = 1;