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

Shawn Guo shawn.guo at freescale.com
Wed Dec 7 08:43:36 EST 2011


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 at KARO-electronics.de>
> > > ---
> > >  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 at linaro.org>

-- 
Regards,
Shawn




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