Re: [v3] net: ethernet: cavium: octeon: octeon_mgmt: Handle return NULL error from devm_ioremap

[arvind Yadav]

Hi David,

I did not tested this feature.  I have build it and flashed on hardware.
You can check below commit id. Which has similar check for ioremap.
1- Commit id - de9e397e40f56b9f34af4bf6a5bd7a75ea02456c
      In 'drivers/net/phy/mdio-octeon.c'

2- Commit id - 592569de4c247fe4f25db8369dc0c63860f9560b
      In 'drivers/gpio/gpio-octeon.c'

Thanks
Arvind

On Thursday 15 December 2016 12:58 AM, David Daney wrote:
> On 12/14/2016 11:03 AM, Arvind Yadav wrote:
> > Here, If devm_ioremap will fail. It will return NULL.
> > Kernel can run into a NULL-pointer dereference.
> > This error check will avoid NULL pointer dereference. t
>
> I have asked you twice already this question, but could not determine 
> from your response what the answer is:
>
> Q: Have you tested the patch on OCTEON based hardware that contains 
> the "octeon_mgmt" Ethernet ports?  Please answer either "yes" or "no".
>
>
> Thanks,
> David Daney
>
>
> > Signed-off-by: Arvind Yadav <arvind.yadav.cs@xxxxxxxxx>
> > ---
> >  drivers/net/ethernet/cavium/octeon/octeon_mgmt.c | 6 ++++++
> >  1 file changed, 6 insertions(+)
> >
> > diff --git a/drivers/net/ethernet/cavium/octeon/octeon_mgmt.c 
> > b/drivers/net/ethernet/cavium/octeon/octeon_mgmt.c
> > index 4ab404f..33c2fec 100644
> > --- a/drivers/net/ethernet/cavium/octeon/octeon_mgmt.c
> > +++ b/drivers/net/ethernet/cavium/octeon/octeon_mgmt.c
> > @@ -1479,6 +1479,12 @@ static int octeon_mgmt_probe(struct 
> > platform_device *pdev)
> >      p->agl = (u64)devm_ioremap(&pdev->dev, p->agl_phys, p->agl_size);
> >      p->agl_prt_ctl = (u64)devm_ioremap(&pdev->dev, p->agl_prt_ctl_phys,
> >                         p->agl_prt_ctl_size);
> > +    if (!p->mix || !p->agl || !p->agl_prt_ctl) {
> > +        dev_err(&pdev->dev, "failed to map I/O memory\n");
> > +        result = -ENOMEM;
> > +        goto err;
> > +    }
> > +
> >      spin_lock_init(&p->lock);
> >
> >      skb_queue_head_init(&p->tx_list);