Re: [PATCH net] net: phy: smsc: add missed clk_disable_unprepare in smsc_phy_probe()

From: Marco Felsch
Date: Mon Nov 16 2020 - 04:26:51 EST


On 20-11-14 11:45, Florian Fainelli wrote:
>
>
> On 11/14/2020 11:26 AM, Jakub Kicinski wrote:
> > On Thu, 12 Nov 2020 19:23:59 +0800 Zhang Changzhong wrote:
> >> Add the missing clk_disable_unprepare() before return from
> >> smsc_phy_probe() in the error handling case.
> >>
> >> Fixes: bedd8d78aba3 ("net: phy: smsc: LAN8710/20: add phy refclk in support")
> >> Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
> >> Signed-off-by: Zhang Changzhong <zhangchangzhong@xxxxxxxxxx>
> >> ---
> >> drivers/net/phy/smsc.c | 4 +++-
> >> 1 file changed, 3 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/drivers/net/phy/smsc.c b/drivers/net/phy/smsc.c
> >> index ec97669..0fc39ac 100644
> >> --- a/drivers/net/phy/smsc.c
> >> +++ b/drivers/net/phy/smsc.c
> >> @@ -291,8 +291,10 @@ static int smsc_phy_probe(struct phy_device *phydev)
> >> return ret;
> >>
> >> ret = clk_set_rate(priv->refclk, 50 * 1000 * 1000);
> >> - if (ret)
> >> + if (ret) {
> >> + clk_disable_unprepare(priv->refclk);
> >> return ret;
> >> + }
> >>
> >> return 0;
> >> }
> >
> > Applied, thanks!
> >
> > The code right above looks highly questionable as well:
> >
> > priv->refclk = clk_get_optional(dev, NULL);
> > if (IS_ERR(priv->refclk))
> > dev_err_probe(dev, PTR_ERR(priv->refclk), "Failed to request clock\n");
> >
> > ret = clk_prepare_enable(priv->refclk);
> > if (ret)
> > return ret;
> >
> > I don't think clk_prepare_enable() will be too happy to see an error
> > pointer. This should probably be:
> >
> > priv->refclk = clk_get_optional(dev, NULL);
> > if (IS_ERR(priv->refclk))
> > return dev_err_probe(dev, PTR_ERR(priv->refclk),
> > "Failed to request clock\n");
>
> Right, especially if EPROBE_DEFER must be returned because the clock
> provider is not ready yet, we should have a chance to do that.

Hi,

damn.. I missed the return here. Thanks for covering that. Should I send
a fix or did you do that already?

Regards,
Marco