On Thu, 23 Jan 2025 13:33:30 +0200
Claudiu Beznea <claudiu.beznea@xxxxxxxxx> wrote:
> Hi, Kory,
>
> On 22.01.2025 18:19, Kory Maincent wrote:
> > Fix the suspend path by ensuring the rtnl lock is held where required.
> > Calls to ravb_open, ravb_close and wol operations must be performed under
> > the rtnl lock to prevent conflicts with ongoing ndo operations.
>
> I've test it. Looks good.
>
> Thank you for your patch. However, I think this could be simplified. The
> locking scheme looks complicated to me. E.g., this one works too:
>
> diff --git a/drivers/net/ethernet/renesas/ravb_main.c
> b/drivers/net/ethernet/renesas/ravb_main.c
> index bc395294a32d..cfe4f0f364f3 100644
> --- a/drivers/net/ethernet/renesas/ravb_main.c
> +++ b/drivers/net/ethernet/renesas/ravb_main.c
> @@ -3217,10 +3217,16 @@ static int ravb_suspend(struct device *dev)
>
> netif_device_detach(ndev);
>
> - if (priv->wol_enabled)
> - return ravb_wol_setup(ndev);
> + if (priv->wol_enabled) {
> + rtnl_lock();
> + ret = ravb_wol_setup(ndev);
> + rtnl_unlock();
> + return ret;
> + }
What happen if wol_enabled flag changes it state between the rtnl_lock and the
if condition? We will be in the wrong path.
Regards,
--
Köry Maincent, Bootlin
Embedded Linux and kernel engineering
https://bootlin.com
