Hello, Dan,
> > >
> > > We might not have a phy so we need to check for NULL before calling
> > > phy_stop(netdev->phydev) or it could lead to an Oops.
> > >
> > > Fixes: e24a6c874601 ("net: ftgmac100: Get link speed and duplex for
> > > NC-SI")
> > > Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> > > ---
> > > drivers/net/ethernet/faraday/ftgmac100.c | 3 ++-
> > > 1 file changed, 2 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/net/ethernet/faraday/ftgmac100.c
> > > b/drivers/net/ethernet/faraday/ftgmac100.c
> > > index f3cc14cc757d..0e873e6f60d6 100644
> > > --- a/drivers/net/ethernet/faraday/ftgmac100.c
> > > +++ b/drivers/net/ethernet/faraday/ftgmac100.c
> > > @@ -1565,7 +1565,8 @@ static int ftgmac100_open(struct net_device
> > > *netdev)
> > > return 0;
> > >
> > > err_ncsi:
> > > - phy_stop(netdev->phydev);
> > > + if (netdev->phydev)
> > > + phy_stop(netdev->phydev);
> > When using " use-ncsi" property, the driver will register a fixed-link
> > phy device and bind to netdev at probe stage.
> >
> > if (np && of_get_property(np, "use-ncsi", NULL)) {
> >
> > ......
> >
> > phydev = fixed_phy_register(PHY_POLL, &ncsi_phy_status, NULL);
> > err = phy_connect_direct(netdev, phydev, ftgmac100_adjust_link,
> > PHY_INTERFACE_MODE_MII);
>
> This is another bug. There needs to be error checking in case
> fixed_phy_register() fails, other wise it crashes when we call
> phy_connect_direct(). For example, if the probe() ordering is unlucky
> fixed_phy_register() can return -EPROBE_DEFER so it's not even unusual error
> cases, which can lead to a crash but just normal stuff.
You are right. It is my fault.
I did miss checking the return status of the fixed_phy_register() function.
Thank you for reminding me this bug.
>
> > if (err) {
> > dev_err(&pdev->dev, "Connecting PHY failed\n");
> > goto err_phy_connect;
> > }
> > } else if (np && of_phy_is_fixed_link(np)) {
> >
> > Therefore, it does not need to check if the point is NULL in this error
> handling.
> > Thanks.
>
> It's really unsafe to assume that we will never add more gotos to the
> ftgmac100_open() function. If you insist, I could remove the Fixes tag... Let
> me know.
I will refine this part and send the other patch to fix my bug. Thank you.
>
>
> regards,
> dan carpenter
