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Subject: Re: [PATCH 1/1] clk: tegra: tegra124-emc: Fix possible memory leak
To:     Stephen Boyd <sboyd@kernel.org>,
        Jonathan Hunter <jonathanh@nvidia.com>,
        "Leizhen (ThunderTown)" <thunder.leizhen@huawei.com>,
        Michael Turquette <mturquette@baylibre.com>,
        Peter De Schrijver <pdeschrijver@nvidia.com>,
        Prashant Gaikwad <pgaikwad@nvidia.com>,
        Thierry Reding <thierry.reding@gmail.com>,
        linux-clk <linux-clk@vger.kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        linux-tegra <linux-tegra@vger.kernel.org>
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 <a6f88419-2cb9-0717-7737-e4666cdcc211@huawei.com>
 <162483744494.3259633.12565750309559171999@swboyd.mtv.corp.google.com>
From:   Dmitry Osipenko <digetx@gmail.com>
Message-ID: <5eb50fd9-1de9-cc61-6443-d84999e22803@gmail.com>
Date:   Mon, 28 Jun 2021 03:29:20 +0300
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28.06.2021 02:44, Stephen Boyd пишет:
> Quoting Leizhen (ThunderTown) (2021-06-25 18:32:46)
>>
>>
>> On 2021/6/26 7:31, Stephen Boyd wrote:
>>> Quoting Zhen Lei (2021-06-17 01:27:59)
>>>> When krealloc() fails to expand the memory and returns NULL, the original
>>>> memory is not released. In this case, the original "timings" scale should
>>>> be maintained.
>>>>
>>>> Fixes: 888ca40e2843 ("clk: tegra: emc: Support multiple RAM codes")

The memory is still not released on error and this is not the only one
place in that code which doesn't release memory on error.

All this code is executed only once during early kernel boot, perhaps
not really worthwhile fixing it or at least this should be done properly.

>>>> Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
>>>> ---
>>>
>>> Looks correct, but when does krealloc() return NULL? My read of the
>>> kerneldoc is that it would return the original memory if the new
>>> allocation "failed".
>>
>> That must be the wrong description in the document. For example, the original
> 
> Can you fix the kernel doc then?
> 

The doc is clearly saying that it returns NULL, am I missing something?

* Return: pointer to the allocated memory or %NULL in case of error