From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Brian Norris , Pekon Gupta Subject: [PATCH 3.15 023/122] mtd: nand: omap: fix BCHx ecc.correct to return detected bit-flips in erased-page Date: Mon, 7 Jul 2014 16:56:25 -0700 Message-Id: <20140707235734.942717975@linuxfoundation.org> In-Reply-To: <20140707235734.234226883@linuxfoundation.org> References: <20140707235734.234226883@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: pekon gupta commit f306e8c3b667632952f1a4a74ffb910bbc06255f upstream. 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 Signed-off-by: Pekon Gupta Signed-off-by: Brian Norris Signed-off-by: Greg Kroah-Hartman --- drivers/mtd/nand/omap2.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/mtd/nand/omap2.c +++ b/drivers/mtd/nand/omap2.c @@ -1382,7 +1382,7 @@ static int omap_elm_correct_data(struct /* Check if any error reported */ if (!is_error_reported) - return 0; + return stat; /* Decode BCH error using ELM module */ elm_decode_bch_error_page(info->elm_dev, ecc_vec, err_vec);