From patchwork Wed Aug 31 01:45:36 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Brian Norris X-Patchwork-Id: 112419 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 0F952B6F7B for ; Wed, 31 Aug 2011 11:48:57 +1000 (EST) Received: from canuck.infradead.org ([2001:4978:20e::1]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1QyZuy-0008FI-I9; Wed, 31 Aug 2011 01:48:40 +0000 Received: from localhost ([127.0.0.1] helo=canuck.infradead.org) by canuck.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1QyZuy-00059X-23; Wed, 31 Aug 2011 01:48:40 +0000 Received: from mms2.broadcom.com ([216.31.210.18]) by canuck.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1QyZuu-00059D-Gq for linux-mtd@lists.infradead.org; Wed, 31 Aug 2011 01:48:37 +0000 Received: from [10.9.200.131] by mms2.broadcom.com with ESMTP (Broadcom SMTP Relay (Email Firewall v6.3.2)); Tue, 30 Aug 2011 18:54:16 -0700 X-Server-Uuid: D3C04415-6FA8-4F2C-93C1-920E106A2031 Received: from mail-irva-13.broadcom.com (10.11.16.103) by IRVEXCHHUB01.corp.ad.broadcom.com (10.9.200.131) with Microsoft SMTP Server id 8.2.247.2; Tue, 30 Aug 2011 18:48:27 -0700 Received: from ld-irv-0074.broadcom.com (ld-irv-0074 [10.12.160.50]) by mail-irva-13.broadcom.com (Postfix) with ESMTP id 27BA974D04; Tue, 30 Aug 2011 18:48:27 -0700 (PDT) From: "Brian Norris" To: "Artem Bityutskiy" Subject: [PATCH 01/12] mtd: nand: initialize chip->oob_poi before write Date: Tue, 30 Aug 2011 18:45:36 -0700 Message-ID: <1314755147-17756-2-git-send-email-computersforpeace@gmail.com> X-Mailer: git-send-email 1.7.5.4 In-Reply-To: <1314755147-17756-1-git-send-email-computersforpeace@gmail.com> References: <1314755147-17756-1-git-send-email-computersforpeace@gmail.com> MIME-Version: 1.0 X-WSS-ID: 62434BC23W410451630-01-01 X-CRM114-Version: 20090807-BlameThorstenAndJenny ( TRE 0.7.6 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20110830_214836_774718_50EC23A9 X-CRM114-Status: GOOD ( 14.52 ) X-Spam-Score: -1.1 (-) X-Spam-Report: SpamAssassin version 3.3.1 on canuck.infradead.org summary: Content analysis details: (-1.1 points) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at http://www.dnswl.org/, medium trust [216.31.210.18 listed in list.dnswl.org] 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (computersforpeace[at]gmail.com) 0.0 DKIM_ADSP_CUSTOM_MED No valid author signature, adsp_override is CUSTOM_MED 1.2 NML_ADSP_CUSTOM_MED ADSP custom_med hit, and not from a mailing list Cc: Ricard Wanderlof , Kevin Cernekee , b35362@freescale.com, linux-mtd@lists.infradead.org, Adam Thomson , Brian Norris , David Woodhouse X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-mtd-bounces@lists.infradead.org Errors-To: linux-mtd-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org For raw (i.e., w/o ECC) page writes (i.e., w/o OOB), we may not have initialized and filled the chip->oob_poi buffer. This can end up writing junk to the flash if we're not careful. Say, for example, we use `nandwrite -n' (without OOB). Then nand_do_write_ops calls chip->write_page, which writes OOB data with some previous, junk data. This fixes a bug with this commit (from l2-mtd-2.6.git): commit a8ee364bbf14861d5d0af39c4da06c30441895fb mtd: nand_base: always initialise oob_poi before writing OOB data That commit removed the memset from under a conditional for: if (likely(!oob)) and moved it (indirectly) to the `nand_fill_oob()' function, which was under: if (unlikely(oob)) Though the "likely" and "unlikely" can be confusing, these are not the same conditions :) And if the buggy commit is going stable, this should go stable (or just amend it) as well. Signed-off-by: Brian Norris Cc: Adam Thomson --- If the buggy commit is going into -stable, this should go -stable as well (or just amend the original). drivers/mtd/nand/nand_base.c | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-) diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c index d2ee68a..273e6a5 100644 --- a/drivers/mtd/nand/nand_base.c +++ b/drivers/mtd/nand/nand_base.c @@ -2227,6 +2227,9 @@ static int nand_do_write_ops(struct mtd_info *mtd, loff_t to, size_t len = min(oobwritelen, oobmaxlen); oob = nand_fill_oob(mtd, oob, len, ops); oobwritelen -= len; + } else { + /* We still need to erase leftover OOB data */ + memset(chip->oob_poi, 0xff, mtd->oobsize); } ret = chip->write_page(mtd, chip, wbuf, page, cached,