Subject: Re: [PATCH] usb: dwc3: dwc3-qcom: Add missing platform_device_put()
 in dwc3_qcom_acpi_register_core
To:     Miaoqian Lin <linmq006@gmail.com>
Cc:     Andy Gross <agross@kernel.org>,
        Bjorn Andersson <bjorn.andersson@linaro.org>,
        Felipe Balbi <balbi@kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-arm-msm@vger.kernel.org, linux-usb@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20211231113641.31474-1-linmq006@gmail.com>
From:   Vladimir Zapolskiy <vladimir.zapolskiy@linaro.org>
Message-ID: <83d55401-d8b3-f709-c77a-fa0e09fda27f@linaro.org>
Date:   Tue, 4 Jan 2022 22:10:33 +0200
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On 12/31/21 1:36 PM, Miaoqian Lin wrote:
> Add the missing platform_device_put() before return from
> dwc3_qcom_acpi_register_core in the error handling case.
> 

The discovered issue is valid.

Fixes: 2bc02355f8ba ("usb: dwc3: qcom: Add support for booting with ACPI")

> Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
> ---
>   drivers/usb/dwc3/dwc3-qcom.c | 8 +++++++-
>   1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/dwc3/dwc3-qcom.c b/drivers/usb/dwc3/dwc3-qcom.c
> index 3cb01cdd02c2..5257783f17b0 100644
> --- a/drivers/usb/dwc3/dwc3-qcom.c
> +++ b/drivers/usb/dwc3/dwc3-qcom.c
> @@ -598,8 +598,10 @@ static int dwc3_qcom_acpi_register_core(struct platform_device *pdev)
>   	qcom->dwc3->dev.coherent_dma_mask = dev->coherent_dma_mask;
>   
>   	child_res = kcalloc(2, sizeof(*child_res), GFP_KERNEL);
> -	if (!child_res)
> +	if (!child_res) {
> +		platform_device_put(qcom->dwc3);
>   		return -ENOMEM;

Please do it in a unified way along all checks:

		ret = -ENOMEM;
		goto out;

kfree(NULL) is legit, please utilize it.

> +	}
>   
>   	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>   	if (!res) {
> @@ -637,9 +639,13 @@ static int dwc3_qcom_acpi_register_core(struct platform_device *pdev)
>   	if (ret) {
>   		dev_err(&pdev->dev, "failed to add device\n");
>   		device_remove_software_node(&qcom->dwc3->dev);
> +		goto out;
>   	}

Please add a blank line here after the closing curly bracket.

> +	kfree(child_res);
> +	return 0;
>   
>   out:
> +	platform_device_put(qcom->dwc3);
>   	kfree(child_res);
>   	return ret;
>   }
> 

Reviewed-by: Vladimir Zapolskiy <vladimir.zapolskiy@linaro.org>

--
Best wishes,
Vladimir