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

From	Bin Liu <b-liu@ti.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH v3 15/16] usb: musb: da8xx: Use devm in probe
Date	2016-04-01 17:00 +0200
Message-ID	<rj8Ii-5RJ-13@gated-at.bofh.it> (permalink)
References	<rgnku-1AF-3@gated-at.bofh.it> <rgnkv-1AF-33@gated-at.bofh.it> <riTgd-3dz-1@gated-at.bofh.it> <riTgd-3dz-5@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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Hi,

On Thu, Mar 31, 2016 at 05:28:48PM -0500, David Lechner wrote:
> 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.

Ah, right.

> 
> 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.
> 
Ok.

Signed-off-by: Bin Liu <b-liu@ti.com>

Regards,
-Bin.

Thread

[PATCH v3 00/16] da8xx USB clocks David Lechner <david@lechnology.com> - 2016-03-25 01:00 +0100
  [PATCH v3 15/16] usb: musb: da8xx: Use devm in probe David Lechner <david@lechnology.com> - 2016-03-25 01:00 +0100
    Re: [PATCH v3 15/16] usb: musb: da8xx: Use devm in probe Bin Liu <b-liu@ti.com> - 2016-04-01 00:30 +0200
      Re: [PATCH v3 15/16] usb: musb: da8xx: Use devm in probe David Lechner <david@lechnology.com> - 2016-04-01 00:30 +0200
        Re: [PATCH v3 15/16] usb: musb: da8xx: Use devm in probe Bin Liu <b-liu@ti.com> - 2016-04-01 17:00 +0200
      Re: [PATCH v3 15/16] usb: musb: da8xx: Use devm in probe Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> - 2016-04-01 12:40 +0200
  [PATCH v3 11/16] ARM: davinci: da8xx: Add USB PHY platform declaration David Lechner <david@lechnology.com> - 2016-03-25 01:00 +0100
  [PATCH v3 12/16] ARM: dt: da850: Add cfgchip syscon node David Lechner <david@lechnology.com> - 2016-03-25 01:00 +0100
  [PATCH v3 07/16] ARM: davinci: da8xx: add usb phy clocks David Lechner <david@lechnology.com> - 2016-03-25 01:00 +0100
  [PATCH v3 13/16] ARM: dt: da850: Add usb phy node David Lechner <david@lechnology.com> - 2016-03-25 01:00 +0100

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