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Date: Tue, 13 Jan 2015 10:56:19 +0800
From: Huang Shijie <shijie.huang@intel.com>
To: Brian Norris <computersforpeace@gmail.com>
Subject: Re: [PATCH] mtd: nand: default bitflip-reporting threshold to 75% of
 correction strength
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Cc: Ricard Wanderlof <ricard.wanderlof@axis.com>,
 Richard Weinberger <richard@nod.at>, Steve deRosier <derosier@gmail.com>,
 Josh Wu <josh.wu@atmel.com>,
 "linux-mtd@lists.infradead.org" <linux-mtd@lists.infradead.org>,
 Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>,
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On Mon, Jan 12, 2015 at 06:38:49PM -0800, Brian Norris wrote:
> On Mon, Jan 12, 2015 at 6:01 PM, Huang Shijie <shijie.huang@intel.com> wrote:
> > On Mon, Jan 12, 2015 at 12:51:29PM -0800, Brian Norris wrote:
> >> --- a/drivers/mtd/nand/nand_base.c
> >> +++ b/drivers/mtd/nand/nand_base.c
> >> @@ -4171,7 +4171,7 @@ int nand_scan_tail(struct mtd_info *mtd)
> >>        * properly set.
> >>        */
> >>       if (!mtd->bitflip_threshold)
> >> -             mtd->bitflip_threshold = mtd->ecc_strength;
> >> +             mtd->bitflip_threshold = DIV_ROUND_UP(mtd->ecc_strength * 3, 4);
> > After this patch, we have to change the bitflip_threshold to
> > ecc_strength manually when we do the mtd_biterrors.ko test.
> 
> Why?
sorry, I misunderstood the mtd_biterrors code.
It is fine after this patch.

thanks
Huang Shijie