Re: [PATCH v3 15/16] usb: musb: da8xx: Use devm in probe

[David Lechner]

On 03/31/2016 05:21 PM, Bin Liu wrote:

> > -	glue = kzalloc(sizeof(*glue), GFP_KERNEL);
> > +	glue = devm_kzalloc(&pdev->dev, sizeof(*glue), GFP_KERNEL);
> >   	if (!glue) {
> >   		dev_err(&pdev->dev, "failed to allocate glue context\n");
> > -		goto err0;
> > +		return -ENOMEM;
> >   	}
> >
> > -	clk = clk_get(&pdev->dev, "usb20");
> > +	clk = devm_clk_get(&pdev->dev, "usb20");
> >   	if (IS_ERR(clk)) {
> >   		dev_err(&pdev->dev, "failed to get clock\n");
> > -		ret = PTR_ERR(clk);
> > -		goto err3;
> > +		return PTR_ERR(clk);
>
> memory leak due to not kfree(glue).

It is my understanding that since glue is allocated with devm_kzalloc(), 
that if the probe function returns and error, glue and everything else 
allocated with devm_* will be automatically freed.

If this is not the case, wouldn't devm_kfree() be the appropriate 
function instead?


> > @@ -576,8 +569,6 @@ static int da8xx_remove(struct platform_device *pdev)
> >   	platform_device_unregister(glue->musb);
> >   	usb_phy_generic_unregister(glue->phy);
> >   	clk_disable(glue->clk);
> > -	clk_put(glue->clk);
> > -	kfree(glue);
>
> Doesn't match with $subject, I'd put them into a seperate patch.


I disagree. Since these are now automatically freed because of changes 
in the probe function, these changes belong in the same patch.