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SubjectRe: [PATCH NET V5 2/2] net: hns: Use phy_driver to setup Phy loopback
> >>From your description, it sounds like you can call phy_resume() on a
> > device which is not suspended.
> Do you mean after calling dev_close, the device is still not suspended?

You only call dev_close() if the device is running. What if somebody
runs the self test on an interface when it has never been opened? It
looks like you will call phy_resume(). But since it has never been
suspended, you could be in trouble.
>
> In general, suspend is expected to
> > store away state which will be lost when powering down a
> > device. Resume writes that state back into the device after it is
> > powered up. So resuming a device which was never suspended could write
> > bad state into it.
>
> Do you mean phydev->suspended has bad state?

phy_resume() current does not check the phydev->suspended state.

> > Also, what about if WOL has been set before closing the device?
>
> phy_suspend will return errro.
>
> int phy_suspend(struct phy_device *phydev)
> {
> struct phy_driver *phydrv = to_phy_driver(phydev->mdio.dev.driver);
> struct ethtool_wolinfo wol = { .cmd = ETHTOOL_GWOL };
> int ret = 0;
>
> /* If the device has WOL enabled, we cannot suspend the PHY */
> phy_ethtool_get_wol(phydev, &wol);
> if (wol.wolopts)
> return -EBUSY;
>
> if (phydev->drv && phydrv->suspend)
> ret = phydrv->suspend(phydev);
>
> if (ret)
> return ret;
>
> phydev->suspended = true;
>
> return ret;
> }

Which means when you call phy_resume() in lb_setup() you are again
resuming a device which is not suspended...

Andrew

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