Re: [PATCH 2/2] net: macb: Unregister nedev before MDIO bus in remove

From: Russell King (Oracle)
Date: Sun Nov 26 2023 - 12:49:56 EST


On Sun, Nov 26, 2023 at 06:13:55PM +0100, Andrew Lunn wrote:
> > diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
> > index cebae0f418f2..73d041af3de1 100644
> > --- a/drivers/net/ethernet/cadence/macb_main.c
> > +++ b/drivers/net/ethernet/cadence/macb_main.c
> > @@ -5165,11 +5165,11 @@ static void macb_remove(struct platform_device *pdev)
> >
> > if (dev) {
> > bp = netdev_priv(dev);
> > + unregister_netdev(dev);
> > phy_exit(bp->sgmii_phy);
> > mdiobus_unregister(bp->mii_bus);
> > mdiobus_free(bp->mii_bus);
> >
> > - unregister_netdev(dev);
> > tasklet_kill(&bp->hresp_err_tasklet);
>
>
> I don't know this driver...
>
> What does this tasklet do? Is it safe for it to run after the netdev
> is unregistered, and the PHY and the mdio bus is gone? Maybe this
> tasklet_kill should be after the interrupt is disabled, but before the
> netdev is unregistered?

.. and while evaluating Andrew's comment, check whether the tasklet
is necessary for the device to successfully close or not - remembering
that unregister_netdev() will close down an open netdev.

--
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