Re: [PATCH] mtd: spinand: fix error read return value

[liaoweixiong]

hi Boris Brezillon,

Sure, i will adjust the commit message and send again right now.

On 2019/6/20 AM12:18, Boris Brezillon wrote:
> On Wed, 19 Jun 2019 14:02:14 +0000
> Schrempf Frieder <frieder.schrempf@xxxxxxxxxx> wrote:
> 
>> On 19.06.19 15:46, Boris Brezillon wrote:
>>> Hi liaoweixiong,
>>>
>>> On Wed, 19 Jun 2019 21:13:24 +0800
>>> liaoweixiong <liaoweixiong@xxxxxxxxxxxxxxxxx> wrote:
>>>   
>>>> In function spinand_mtd_read, if the last page to read occurs bitflip,
>>>> this function will return error value because veriable ret not equal to 0.  
>>>
>>> Actually, that's exactly what the MTD core expects (see [1]), so you're
>>> the one introducing a regression here.  
>>
>> To me it looks like the patch description is somewhat incorrect, but the 
>> fix itself looks okay, unless I'm getting it wrong.
>>
>> In case of the last page containing bitflips (ret > 0), 
>> spinand_mtd_read() will return that number of bitflips for the last 
>> page. But to me it looks like it should instead return max_bitflips like 
>> it does when the last page read returns with 0.
> 
> Oh, you're right. liaoweixiong, can you adjust the commit message
> accordingly?
> 
>>
>>>>
>>>> Signed-off-by: liaoweixiong <liaoweixiong@xxxxxxxxxxxxxxxxx>
>>>> ---
>>>>   drivers/mtd/nand/spi/core.c | 2 +-
>>>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>>>
>>>> diff --git a/drivers/mtd/nand/spi/core.c b/drivers/mtd/nand/spi/core.c
>>>> index 556bfdb..6b9388d 100644
>>>> --- a/drivers/mtd/nand/spi/core.c
>>>> +++ b/drivers/mtd/nand/spi/core.c
>>>> @@ -511,12 +511,12 @@ static int spinand_mtd_read(struct mtd_info *mtd, loff_t from,
>>>>   		if (ret == -EBADMSG) {
>>>>   			ecc_failed = true;
>>>>   			mtd->ecc_stats.failed++;
>>>> -			ret = 0;
>>>>   		} else {
>>>>   			mtd->ecc_stats.corrected += ret;
>>>>   			max_bitflips = max_t(unsigned int, max_bitflips, ret);
>>>>   		}
>>>>   
>>>> +		ret = 0;
>>>>   		ops->retlen += iter.req.datalen;
>>>>   		ops->oobretlen += iter.req.ooblen;
>>>>   	}  
>>>
>>> [1]https://elixir.bootlin.com/linux/latest/source/drivers/mtd/mtdcore.c#L1209
>>>
>>> ______________________________________________________
>>> Linux MTD discussion mailing list
>>> http://lists.infradead.org/mailman/listinfo/linux-mtd/
>>>  

-- 
liaoweixiong