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Message-ID: <37c23054-1590-b33d-9299-7d5d6198f8f0@wanadoo.fr>
Date:   Thu, 27 Apr 2023 22:29:34 +0200
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Subject: Re: [PATCH 2/2] serial: 8250_bcm7271: fix leak in `brcmuart_probe`
To:     Doug Berger <opendmb@gmail.com>
Cc:     Al Cooper <alcooperx@gmail.com>,
        XuDong Liu <m202071377@hust.edu.cn>,
        Dongliang Mu <dzm91@hust.edu.cn>,
        Jiri Slaby <jirislaby@kernel.org>,
        Florian Fainelli <f.fainelli@gmail.com>,
        Broadcom internal kernel review list 
        <bcm-kernel-feedback-list@broadcom.com>,
        linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>
References: <20230427181916.2983697-1-opendmb@gmail.com>
 <20230427181916.2983697-3-opendmb@gmail.com>
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From:   Christophe JAILLET <christophe.jaillet@wanadoo.fr>
In-Reply-To: <20230427181916.2983697-3-opendmb@gmail.com>
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Le 27/04/2023 à 20:19, Doug Berger a écrit :
> Smatch reports:
> drivers/tty/serial/8250/8250_bcm7271.c:1120 brcmuart_probe() warn:
> 'baud_mux_clk' from clk_prepare_enable() not released on lines: 1032.
> 
> The issue is fixed by using a managed clock.
> 
> Fixes: 41a469482de2 ("serial: 8250: Add new 8250-core based Broadcom STB driver")
> Reported-by: XuDong Liu <m202071377@hust.edu.cn>
> Link: https://lore.kernel.org/lkml/20230424125100.4783-1-m202071377@hust.edu.cn/
> Signed-off-by: Doug Berger <opendmb@gmail.com>
> ---
>   drivers/tty/serial/8250/8250_bcm7271.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/tty/serial/8250/8250_bcm7271.c b/drivers/tty/serial/8250/8250_bcm7271.c
> index 90ee7bc12f77..af0e1c070187 100644
> --- a/drivers/tty/serial/8250/8250_bcm7271.c
> +++ b/drivers/tty/serial/8250/8250_bcm7271.c
> @@ -1012,7 +1012,7 @@ static int brcmuart_probe(struct platform_device *pdev)
>   	of_property_read_u32(np, "clock-frequency", &clk_rate);
>   
>   	/* See if a Baud clock has been specified */
> -	baud_mux_clk = of_clk_get_by_name(np, "sw_baud");
> +	baud_mux_clk = devm_clk_get(dev, "sw_baud");

If switching to devm_clk_get(), maybe devm_clk_get_enabled() could also 
be an option to fix both issues and avoid adding some LoC.

The order of operation in the remove function would then be different. I 
don't know if it can be an issue.

Just my 2c.

CJ

>   	if (IS_ERR(baud_mux_clk)) {
>   		if (PTR_ERR(baud_mux_clk) == -EPROBE_DEFER) {
>   			ret = -EPROBE_DEFER;