Re: [Patch v3 2/2] memory: tegra: make sid and broadcast regions optional

From: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
To: Sumit Gupta <sumitg@nvidia.com>,
	"robh@kernel.org" <robh@kernel.org>,
	"conor+dt@kernel.org" <conor+dt@kernel.org>,
	"maz@kernel.org" <maz@kernel.org>,
	"mark.rutland@arm.com" <mark.rutland@arm.com>,
	Thierry Reding <treding@nvidia.com>,
	Jon Hunter <jonathanh@nvidia.com>
Cc: "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"linux-tegra@vger.kernel.org" <linux-tegra@vger.kernel.org>,
	Ashish Mhetre <amhetre@nvidia.com>, Bibek Basu <bbasu@nvidia.com>
Subject: Re: [Patch v3 2/2] memory: tegra: make sid and broadcast regions optional
Date: Wed, 24 Apr 2024 07:44:16 +0200	[thread overview]
Message-ID: <4824ad5c-0250-43cb-8f92-ec5e6c9c49af@linaro.org> (raw)
In-Reply-To: <95f8e4b5-23af-90cb-4dae-2922e8e71920@nvidia.com>

On 24/04/2024 07:27, Sumit Gupta wrote:
> 
> 
>>>
>>>>>>>
>>>>>>>     static inline u32 mc_readl(const struct tegra_mc *mc, unsigned long offset)
>>>>>>> diff --git a/drivers/memory/tegra/tegra186.c b/drivers/memory/tegra/tegra186.c
>>>>>>> index 1b3183951bfe..716582255eeb 100644
>>>>>>> --- a/drivers/memory/tegra/tegra186.c
>>>>>>> +++ b/drivers/memory/tegra/tegra186.c
>>>>>>> @@ -26,20 +26,16 @@
>>>>>>>     static int tegra186_mc_probe(struct tegra_mc *mc)
>>>>>>>     {
>>>>>>>          struct platform_device *pdev = to_platform_device(mc->dev);
>>>>>>> +     struct resource *res;
>>>>>>>          unsigned int i;
>>>>>>> -     char name[8];
>>>>>>> +     char name[14];
>>>>>>
>>>>>> How is it relevant? I don't see this being used in your diff.
>>>>>>
>>>>>>
>>>>>> Best regards,
>>>>>> Krzysztof
>>>>>>
>>>>>
>>>>> Did this change for below warning coming with 'W=1'.
>>>>>
>>>>> ../drivers/memory/tegra/tegra186.c: In function tegra186_mc_probe:
>>>>> ../drivers/memory/tegra/tegra186.c:51:49: warning: %u directive output
>>>>> may be truncated writing between 1 and 10 bytes into a region of size 6
>>>>> [8;;https://gc
>>>>> c.gnu.org/onlinedocs/gcc/Warning-Options.html#index-Wformat-truncation=-Wformat-truncation=8;;]
>>>>>       51 |                 snprintf(name, sizeof(name), "ch%u", i);
>>>>>          |                                                 ^~
>>>>> ../drivers/memory/tegra/tegra186.c:51:46: note: directive argument in
>>>>> the range [0, 4294967294]
>>>>>       51 |                 snprintf(name, sizeof(name), "ch%u", i);
>>>>>          |                                              ^~~~~~
>>>>> ../drivers/memory/tegra/tegra186.c:51:17: note: snprintf output between
>>>>> 4 and 13 bytes into a destination of size 8
>>>>>       51 |                 snprintf(name, sizeof(name), "ch%u", i);
>>>>>          |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>>>
>>>> I asked how this is relevant to this change and you answer there is a
>>>> warning. If the warning was there, your answer is really just deflecting
>>>> the topic, so obviously this is new warning. Which part of code uses
>>>> longer name?
>>>>
>>>> BTW, really, such answers do not make review of your code smoother.
>>>>
>>>> Best regards,
>>>> Krzysztof
>>>>
>>>
>>> Apologies for not explaining it earlier.
>>>
>>> I increased the buffer size to suppress a static check warning in the
>>> existing code due to big range of 'unsigned int i', if copied to small
>>> name buffer.
>>>
>>> Seems like the warning is harmless as the maximum value of num_channels
>>> is 16. I will remove it and keep the buffer size as 8 in the next
>>> version.
>>>
>>
>> That's not the point. For the third time: how is it relevant to this
>> change here? Was or was not the warning before?
>>
> 
> This is not relevant to the change here. The warning was before as well.

OK, fixing the warning is always a good idea, but this *must* be always
separate patch, with its own explanation and rationale, and warning message.

Best regards,
Krzysztof