Re: [PATCH net v2] net: macb: fix an issue about leak related system resources

[Dejin Zheng]

On Wed, Apr 29, 2020 at 04:15:56PM +0200, Nicolas Ferre wrote:
> On 29/04/2020 at 15:56, Dejin Zheng wrote:
> > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> > 
> > A call of the function macb_init() can fail in the function
> > fu540_c000_init. The related system resources were not released
> > then. use devm_platform_ioremap_resource() to replace ioremap()
> > to fix it.
> > 
> > Fixes: c218ad559020ff9 ("macb: Add support for SiFive FU540-C000")
> > Cc: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
> > Reviewed-by: Yash Shah <yash.shah@xxxxxxxxxx>
> > Signed-off-by: Dejin Zheng <zhengdejin5@xxxxxxxxx>
> > ---
> > v1 -> v2:
> >          - Nicolas and Andy suggest use devm_platform_ioremap_resource()
> >            to repalce devm_ioremap() to fix this issue. Thanks Nicolas
> >            and Andy.
> >          - Yash help me to review this patch, Thanks Yash!
> > 
> >   drivers/net/ethernet/cadence/macb_main.c | 8 +-------
> >   1 file changed, 1 insertion(+), 7 deletions(-)
> > 
> > diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
> > index a0e8c5bbabc0..99354e327d1f 100644
> > --- a/drivers/net/ethernet/cadence/macb_main.c
> > +++ b/drivers/net/ethernet/cadence/macb_main.c
> > @@ -4172,13 +4172,7 @@ static int fu540_c000_clk_init(struct platform_device *pdev, struct clk **pclk,
> > 
> >   static int fu540_c000_init(struct platform_device *pdev)
> >   {
> > -       struct resource *res;
> > -
> > -       res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> > -       if (!res)
> > -               return -ENODEV;
> > -
> > -       mgmt->reg = ioremap(res->start, resource_size(res));
> > +       mgmt->reg = devm_platform_ioremap_resource(pdev, 1);
> >          if (!mgmt->reg)
> 
> Is your test valid then?
>
Hi Nicolas:

I just compiled it successfully and I didn't have the hardware of this
driver, so I did not tested it. and this patch only affects the driver
of "sifive,fu540-macb", if these IO addresses can be monopolized by
this driver, this change should be ok.


Hi Yash:

Do you know that these IO addresses can be occupied by this driver
alone? Thank you very much!

BR,
Dejin

> Please use:
> if (IS_ERR(base))
>    return PTR_ERR(base);
> As advised by:
> lib/devres.c:156
>
Thanks!, I will sent it in patch v3.

> Regards,
>   Nicolas
> 
> >                  return -ENOMEM;
> > 
> > --
> > 2.25.0
> > 
> 
> 
> -- 
> Nicolas Ferre