[RFC PATCH 4/4] UBI: Fastmap: Do not add vol if it already exists

[Sheng Yong]

Hi, Richard

On 5/22/2015 4:19 AM, Richard Weinberger wrote:
> Am 21.05.2015 um 12:16 schrieb Richard Weinberger:
>> Am 21.05.2015 um 11:56 schrieb Sheng Yong:
>>> When writing fastmap, there is no guarantee that two same vol ID are
>>> written to flash by mistake. Although this unlikely happens, we still
>>> should check it when attaching.
>>
>> Not sure if I understand the error scenario.
>> How can this happen?
I didn't hit the case, this was just found by codewalking. After I read
more code and though about more unclean reboot and ECC scenario, I agree
with you that there is no way to have two same vol_id saved in different
slots in ubi->volumes[], unless modify it by hand :( .  Thank you for
pointing it out.

thanks,
Sheng
> 
> ...thought a bit more about that.
> I think your fix is correct but unless I'm very
> mistaken one can hit the issue only by modifying the fastmap
> by hand.
> 
> Thanks,
> //richard
> 
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