If fec MDIO write method succeeds its return value comes from call to pm_runtime_get_sync(). But pm_runtime_get_sync() can also return 1.
In case of Micrel KSZ9031 PHY this value will then be returned along the call chain of phy_write() -> ksz9031_extended_write() -> ksz9031_center_flp_timing() -> ksz9031_config_init() -> phy_init_hw() -> phy_attach_direct() -> phy_connect_direct(). Then phy_connect() will cast it into a pointer using ERR_PTR(), which then fec_enet_mii_probe() will try to dereference resulting in an oops. Fix it by normalizing return value of pm_runtime_get_sync() to be zero if positive in MDIO write method. Signed-off-by: Maciej Szmigiero <m...@maciej.szmigiero.name> --- drivers/net/ethernet/freescale/fec_main.c | 4 +++- 1 files changed, 3 insertions(+), 1 deletions(-) diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c index 91925e3..6cc3340 100644 --- a/drivers/net/ethernet/freescale/fec_main.c +++ b/drivers/net/ethernet/freescale/fec_main.c @@ -1816,11 +1816,13 @@ static int fec_enet_mdio_write(struct mii_bus *bus, int mii_id, int regnum, struct fec_enet_private *fep = bus->priv; struct device *dev = &fep->pdev->dev; unsigned long time_left; - int ret = 0; + int ret; ret = pm_runtime_get_sync(dev); if (ret < 0) return ret; + else + ret = 0; fep->mii_timeout = 0; reinit_completion(&fep->mdio_done); -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html