From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 17EA5C43381 for ; Thu, 21 Feb 2019 08:11:06 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D91A42086C for ; Thu, 21 Feb 2019 08:11:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="usXzkOp4" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D91A42086C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=collabora.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=BHuvp/10j7A1zBnty0UwASQmLzY9U4gobTO32byHKuM=; b=usXzkOp4XKzyAV nb9ckblLaijuNBjDbyWT2SRnYO+mDGn8/TTIblhyZjC4HHVY+0lVdbLD08j62Ro55+I8VocOgXWrh Mn2F3zZ99LlP+UrMdf1NmrLAOAiHHlxtwoTIcj7ZkB6i7hYL9vajSljcwk4wlsRXDFzrODB+FavZ7 uCzZUL844whQnBUX/BEVE41yF8aGUAdDY9R6/KO+S3fONbUqJYld9GR9xL6Bmns/gdQF246XrjhUi S9LZQtqBpYZ2IMRzeLNQEVPWirFZyu63FMk45OEDTXfPgFv7lf/NP6l+cSs7yZB/PoPl1ZS7E03A4 FlZlcvz3QhKmMgphd4wg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gwjRf-0002No-ES; Thu, 21 Feb 2019 08:11:03 +0000 Received: from bhuna.collabora.co.uk ([46.235.227.227]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gwjRc-0002NU-4p for linux-mtd@lists.infradead.org; Thu, 21 Feb 2019 08:11:02 +0000 Received: from localhost (unknown [IPv6:2a01:e0a:2c:6930:5cf4:84a1:2763:fe0d]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: bbrezillon) by bhuna.collabora.co.uk (Postfix) with ESMTPSA id D723427F912; Thu, 21 Feb 2019 08:10:58 +0000 (GMT) Date: Thu, 21 Feb 2019 09:10:55 +0100 From: Boris Brezillon To: Sascha Hauer Subject: Re: Prevent Nand page writes on Power failure Message-ID: <20190221091055.266b9627@collabora.com> In-Reply-To: <20190220135820.b2ku2unaxxdqflut@pengutronix.de> References: <20190220135820.b2ku2unaxxdqflut@pengutronix.de> Organization: Collabora X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-redhat-linux-gnu) MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190221_001100_323383_30D2B6D3 X-CRM114-Status: GOOD ( 11.87 ) X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-mtd@lists.infradead.org, kernel@pengutronix.de Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-mtd" Errors-To: linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org Hi Sascha, On Wed, 20 Feb 2019 14:58:20 +0100 Sascha Hauer wrote: > Hi All, > > I have hardware here for which the normal way to turn off is just to cut > the power. When the powercut happens during a NAND page write then we > get more or less completely written pages during next boot. Very rarely > it seems to happen that such a half written page with only very few > flipped bits is erroneously detected as empty and written again which > then results in ECC errors when reading the data. This should definitely be fixed, maybe by lowering the bitflip threshold when doing the empty check. Do you know the ECC strength and the number of bitflips you have when that problem occurs? Regards, Boris ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/