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Date: Mon, 12 May 2014 13:36:26 -0700
From: Brian Norris <computersforpeace@gmail.com>
To: Pekon Gupta <pekon@ti.com>
Subject: Re: [PATCH v2] mtd: nand: omap: fix BCHx ecc.correct to return
 detected bit-flips in erased-page
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Cc: Stefan Roese <sr@denx.de>, linux-mtd <linux-mtd@lists.infradead.org>,
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On Tue, Mar 25, 2014 at 12:28:19PM +0530, Pekon Gupta wrote:
> fixes: commit 62116e5171e00f85a8d53f76e45b84423c89ff34
>        mtd: nand: omap2: Support for hardware BCH error correction.
> 
> In omap_elm_correct_data(), if bitflip_count in an erased-page is within the
> correctable limit (< ecc.strength), then it is not indicated back to the caller
> ecc->read_page().
> This mis-guides upper layers like MTD and UBIFS layer to assume erased-page as
> perfectly clean and use it for writing even if actual bitflip_count was
> dangerously high (bitflip_count > mtd->bitflip_threshold).
> 
> This patch fixes this above issue, by returning 'stats' to caller
> ecc->read_page() under all scenarios.
> 
> Reported-by: Brian Norris <computersforpeace@gmail.com>
> Signed-off-by: Pekon Gupta <pekon@ti.com>

Pushed to l2-mtd.git. Thanks!

Brian