netdev - Re: [PATCH net-next 3/3] epic100: allow nesting of ethtool

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Date:   Mon, 6 Jan 2020 07:08:51 +0100
From:   Michal Kubecek <mkubecek@...e.cz>
To:     netdev@...r.kernel.org
Cc:     Andrew Lunn <andrew@...n.ch>,
        "David S. Miller" <davem@...emloft.net>,
        Maya Erez <merez@...eaurora.org>,
        Kalle Valo <kvalo@...eaurora.org>,
        linux-wireless@...r.kernel.org, wil6210@....qualcomm.com,
        Francois Romieu <romieu@...zoreil.com>,
        linux-kernel@...r.kernel.org,
        Florian Fainelli <f.fainelli@...il.com>
Subject: Re: [PATCH net-next 3/3] epic100: allow nesting of ethtool_ops
 begin() and complete()

On Sun, Jan 05, 2020 at 11:08:32PM +0100, Andrew Lunn wrote:
> > @@ -1435,8 +1436,10 @@ static int ethtool_begin(struct net_device *dev)
> >  	struct epic_private *ep = netdev_priv(dev);
> >  	void __iomem *ioaddr = ep->ioaddr;
> >  
> > +	if (ep->ethtool_ops_nesting == U32_MAX)
> > +		return -EBUSY;
> >  	/* power-up, if interface is down */
> > -	if (!netif_running(dev)) {
> > +	if (ep->ethtool_ops_nesting++ && !netif_running(dev)) {
> >  		ew32(GENCTL, 0x0200);
> >  		ew32(NVCTL, (er32(NVCTL) & ~0x003c) | 0x4800);
> >  	}
> 
> Hi Michal
> 
> In the via-velocity you added:
> 
> +       if (vptr->ethtool_ops_nesting == U32_MAX)
> +               return -EBUSY;
> +       if (!vptr->ethtool_ops_nesting++ && !netif_running(dev))
>                 velocity_set_power_state(vptr, PCI_D0);
>         return 0;
> 
> These two fragments differ by a ! . Is that correct?

You are right, thank you for catching it. This should be 

	if (!ep->ethtool_ops_nesting++ && !netif_running(dev)) {

as well, we only want to wake the device up in the first (outermost)
->begin(). (It would probably do no harm to do it each time but not
doing it in the first would be wrong.)

I'll send v2 in a moment.

Michal