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Message-ID: <05f14aa0-4001-d08d-610e-12749437ec9a@meizu.com>
Date:   Wed, 13 Apr 2022 17:24:33 +0800
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Subject: Re: [PATCH V2] clk: renesas: Fix memory leak of 'cpg'
To:     Geert Uytterhoeven <geert@linux-m68k.org>
CC:     Michael Turquette <mturquette@baylibre.com>,
        Stephen Boyd <sboyd@kernel.org>,
        Linux-Renesas <linux-renesas-soc@vger.kernel.org>,
        linux-clk <linux-clk@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
References: <1649837953-10984-1-git-send-email-baihaowen@meizu.com>
 <CAMuHMdXcNBq5e6K6YUorLCF0hiFsp6VVKrUcy5E4mdAQAbH7Sg@mail.gmail.com>
From:   baihaowen <baihaowen@meizu.com>
In-Reply-To: <CAMuHMdXcNBq5e6K6YUorLCF0hiFsp6VVKrUcy5E4mdAQAbH7Sg@mail.gmail.com>
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在 4/13/22 4:41 PM, Geert Uytterhoeven 写道:
> Hi Haowen,
>
> On Wed, Apr 13, 2022 at 10:30 AM Haowen Bai <baihaowen@meizu.com> wrote:
>> Fix this issue by freeing the cpg when exiting the function in the
>> error/normal path.
>>
>> Signed-off-by: Haowen Bai <baihaowen@meizu.com>
> Thanks for your patch!
>
>> --- a/drivers/clk/renesas/clk-r8a73a4.c
>> +++ b/drivers/clk/renesas/clk-r8a73a4.c
>> @@ -215,7 +215,7 @@ static void __init r8a73a4_cpg_clocks_init(struct device_node *np)
>>
>>         cpg->reg = of_iomap(np, 0);
>>         if (WARN_ON(cpg->reg == NULL))
>> -               return;
>> +               goto out_free_cpg;
> Note that this is a fatal error, i.e. no chance the system will survive this,
> so cleaning up is moot.
>
>>         for (i = 0; i < num_clks; ++i) {
>>                 const char *name;
>> @@ -233,6 +233,9 @@ static void __init r8a73a4_cpg_clocks_init(struct device_node *np)
>>         }
>>
>>         of_clk_add_provider(np, of_clk_src_onecell_get, &cpg->data);
>> +out_free_cpg:
>> +       kfree(cpg);
>> +       kfree(clks);
> Both cpg and clks are still used after returning from this function,
> through the registered clocks and clock provider.
>
>>  }
>>  CLK_OF_DECLARE(r8a73a4_cpg_clks, "renesas,r8a73a4-cpg-clocks",
>>                r8a73a4_cpg_clocks_init);
> NAKed-by: Geert Uytterhoeven <geert+renesas@glider.be>
>
> Gr{oetje,eeting}s,
>
>                         Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
>
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
>                                 -- Linus Torvalds
Dear Geert Uytterhoeven
Could you show me how and when cpg & clks free ?

-- 
Haowen Bai