From 42ea4457aea7aaeddf0c0b06724f297608f5e9d2 Mon Sep 17 00:00:00 2001 From: "Maciej S. Szmigiero" Date: Thu, 3 Sep 2015 21:38:30 +0200 Subject: net: fec: normalize return value of pm_runtime_get_sync() in MDIO write 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. Fixes: 8fff755e9f8d ("net: fec: Ensure clocks are enabled while using mdio bus") Signed-off-by: Maciej Szmigiero Acked-by: Andrew Lunn Signed-off-by: David S. Miller --- drivers/net/ethernet/freescale/fec_main.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c index 91925e38705e..6cc334035e07 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); -- cgit v1.2.3-59-g8ed1b