Re: [PATCH][NET] several cleanups and bugfixes for fec.c: fix the.remove code

From: Shawn Guo
Date: Wed Dec 07 2011 - 08:30:58 EST


On Wed, Dec 07, 2011 at 02:26:34PM +0100, Lothar Waßmann wrote:
> Hi,
>
> Shawn Guo writes:
> > On Tue, Dec 06, 2011 at 11:27:15AM +0100, Lothar Waßmann wrote:
> > > The .remove code is broken in several ways.
> > > - mdiobus_unregister() is called twice for the same object in case of dual FEC
> > > - phy_disconnect() is being called when the PHY is already disconnected
> > > - the requested IRQ(s) are not freed
> > > - fec_stop() is being called with the inteface already stopped
> > >
> > > All of those lead to kernel crashes if the remove function is actually used.
> > >
> > > Signed-off-by: Lothar Waßmann <LW@xxxxxxxxxxxxxxxxxxx>
> > > ---
> > > drivers/net/ethernet/freescale/fec.c | 30 +++++++++++++++++++++---------
> > > 1 files changed, 21 insertions(+), 9 deletions(-)
> > >
> > > diff --git a/drivers/net/ethernet/freescale/fec.c b/drivers/net/ethernet/freescale/fec.c
> > > index ab0afb5..70ec7ec 100644
> > > --- a/drivers/net/ethernet/freescale/fec.c
> > > +++ b/drivers/net/ethernet/freescale/fec.c
> > > @@ -235,6 +235,7 @@ struct fec_enet_private {
> > >
> > > /* Phylib and MDIO interface */
> > > struct mii_bus *mii_bus;
> > > + int mii_cnt;
> > > struct phy_device *phy_dev;
> > > int mii_timeout;
> > > uint phy_speed;
> > > @@ -1040,8 +1041,12 @@ static int fec_enet_mii_init(struct platform_device *pdev)
> > > */
> > > if ((id_entry->driver_data & FEC_QUIRK_ENET_MAC) && pdev->id > 0) {
> > > /* fec1 uses fec0 mii_bus */
> > > - fep->mii_bus = fec0_mii_bus;
> > > - return 0;
> > > + if (fep->mii_cnt && fec0_mii_bus) {
> >
> > This seems broken. The second fec has its own fep and fep->mii_cnt is
> > always 0 here.
> >
> I already noticed that myself.
>
With a quick fix here, the last two patches:

Tested-by: Shawn Guo <shawn.guo@xxxxxxxxxx>

--
Regards,
Shawn

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/