Re: [PATCH v2] mtd: rawnand: mark expected switch fall-throughs

From: Gustavo A. R. Silva
Date: Thu Apr 11 2019 - 18:20:37 EST




On 4/11/19 5:10 PM, Miquel Raynal wrote:
> Hi Gustavo,
>
> "Gustavo A. R. Silva" <gustavo@xxxxxxxxxxxxxx> wrote on Thu, 11 Apr
> 2019 13:30:31 -0500:
>
>> Hi Miquel,
>>
>> On 2/5/19 6:55 AM, Miquel Raynal wrote:
>> [..]
>>>> @@ -3280,12 +3280,14 @@ static void onenand_check_features(struct mtd_info *mtd)
>>>> if ((this->version_id & 0xf) == 0xe)
>>>> this->options |= ONENAND_HAS_NOP_1;
>>>> }
>>>> + /* fall through */
>>>>
>>>> case ONENAND_DEVICE_DENSITY_2Gb:
>>>> /* 2Gb DDP does not have 2 plane */
>>>> if (!ONENAND_IS_DDP(this))
>>>> this->options |= ONENAND_HAS_2PLANE;
>>>> this->options |= ONENAND_HAS_UNLOCK_ALL;
>>>> + /* fall through */
>>>
>>> This looks strange.
>>>
>>> In ONENAND_DEVICE_DENSITY_2Gb:
>>> ONENAND_HAS_UNLOCK_ALL is set unconditionally.
>>>
>>> But then, under ONENAND_DEVICE_DENSITY_1Gb, the same option is set only
>>> if process is evaluated to true.
>>>
>>> Same problem with ONENAND_HAS_2PLANE:
>>> - it is set in ONENAND_DEVICE_DENSITY_4Gb only if ONENAND_IS_DDP()
>>> - it is unset in ONENAND_DEVICE_DENSITY_2Gb only if !ONENAND_IS_DDP()
>>>
>>> Maybe this portion should be reworked because I am unsure if this is a
>>> missing fall through or a bug.
>>>
>>
>> I wonder if you had the chance to take a look into this piece of code.
>>
>> Thanks
>> --
>> Gustavo
>
> What do you mean?
>

You commented that the piece of code above should be reworked. So, it wasn't
clear to me who was going to do that; and that's why I'm asking if you took
a look into it and finally determine whether we are dealing with an actual
bug or a false positive.

Thanks
--
Gustavo