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Date: Fri, 3 Jan 2014 23:16:49 +0800
From: Huang Shijie <shijie8@gmail.com>
To: Elie De Brauwer <eliedebrauwer@gmail.com>
Subject: Re: [PATCH v6] mtd: gpmi: Deal with bitflips in erased regions regions
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On Fri, Jan 03, 2014 at 11:34:54AM +0100, Elie De Brauwer wrote:
> >
> > I confirmed with the hardware guy just now.
> > the hardware guy ate his word!
> >
> > If we do not apply this patch, does it mean the UBIFS can not work?
> >
> >
> 
> Thanks for doublechecking ! I'll provide a new version of this patch
> in the weekend.
> 
> If this patch does not get applied you will get bugreports related to
> "corrupt empty space"
> issues when using UBIFS, for the simple reason that ubifs only claims
> to be tolerant to
> corruption due to powercuts, and ubifs relies on the mtd layer that
> bitflips are detected
> and corrected.  In my situation I have already seen two distinct units
> (on a 20 unit population
> over a timespan of about two months) refuse to boot because of this
> issue, which were
> both solved by this patch. So ubifs might seem to work, but people
> using it will likely bump
> into nasty field issues.
I will discuss with our manager next week, and i hope the hardware guy
can fix it in the future.

thanks
Huang Shijie