Hello, Dan
> On Mon, Sep 09, 2024 at 02:03:32PM +0200, Andrew Lunn wrote:
> > > > Are you actually saying:
> > > >
> > > > if (netdev->phydev) {
> > > > /* If we have a PHY, start polling */
> > > > phy_start(netdev->phydev);
> > > > }
> > > >
> > > > is wrong, it is guaranteed there is always a phydev?
> > > >
> > > This patch is focus on error handling when using NC-SI at open stage.
> > >
> > > if (netdev->phydev) {
> > > /* If we have a PHY, start polling */
> > > phy_start(netdev->phydev);
> > > }
> > >
> > > This code is used to check the other cases.
> > > Perhaps, phy-handle or fixed-link property are not added in DTS.
> >
> > I'm guessing, but i think the static analysers see this condition, and
> > deducing that phydev might be a NULL. Hence when phy_stop() is called,
> > it needs the check.
> >
> > You say the static analyser is wrong, probably because it cannot check
> > the bigger context. It can be NULL for phy_start() but not for
> > phy_stop(). Maybe you can give it some more hints?
> >
> > Dan, is this Smatch? Is it possible to dump the paths through the code
> > where it thinks it might be NULL?
>
> Adding a check here is the correct thing. The current code works because we
> only have the one goto after the call to phy_start(netdev->phydev), but as soon
> as we add a second goto then it will crash.
Could you share more detail about the crash is happening when you add a second goto?
I'm wondering if there are other things I missed.
Thank you.
>
> Silencing this warning means tying the information from probe() into it. It's a
> fun problem but not something I'm going to do this year.
>
Jacky
