From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AG47ELvKhYJW2asNwndgeWf9W1gunnLDOKlmberBA2hD5r8BwP6NqTvkPLPl74PqDXDILa2ZF6Ni ARC-Seal: i=1; a=rsa-sha256; t=1520371352; cv=none; d=google.com; s=arc-20160816; b=aEEYJ3aFhfuIevdg21tC2gecA0zvaHUD94kHJOLgQDYb/Tgmg6xt7pxGLz7lH8tiCw 058klykJCqWD+43KzzralhKF0BdxgImrHkTcC4Yw5/aLlanJvDe9LSs93yfmJuxHh5yB X39pnFcPDsSwR0Q6DmAUB+Q6xZVhP0yuNdXQ+/yQrXEhnk4BiwzmYBneH62+HTrcaLQH s3gpKU+phg9wiIhhGsKY5LFliSxijXow+Ou1zPZTOIfA0eHTKvMIjLRDUMDFDUIaVLvz FMMrTQPwyu4jJyT7uD7InCHajZ8nWL9WGijg6xYP7IxWsDYNmPxSfUMD6m8ac1hSeoao wxNw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=content-transfer-encoding:mime-version:organization:references :in-reply-to:date:cc:to:from:subject:message-id :arc-authentication-results; bh=FAeuliIsLghfd/WbXBIrsozHYXzpwcgD5sSWls66X3A=; b=w+3AYoK+cOCnyo0yL6W5igd9nJ/mIwvwXFwOe/nZRsdVPDYy/5gQ4mMjux+a6wagup dKzdplnz03HDt98bUDj0NBsRVqbEnYm+VamHPatd6fnnvngRelvHj+N5P/pnXa5g5Wks NK9A/gESzfwfwD6COeXvLVsXkuyZRKiQ0T3XZ9I0HNos7ar3WGYWGpncbEIxmEYRDb8S UP5GReK2b1TLIzRY2ol4oG4RZnAXqGFx5d8EalX/2NOwkwvu0JOznAnSwRvHfLviyHkA PAtsBtCGoQRa8JO+Gy6JPyD74v/VW5MIvY85D2X5DNBeSpHZuv3gm2fDlro3uRMhyuQY IfGQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of ben.hutchings@codethink.co.uk designates 176.9.8.82 as permitted sender) smtp.mailfrom=ben.hutchings@codethink.co.uk; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=codethink.co.uk Authentication-Results: mx.google.com; spf=pass (google.com: domain of ben.hutchings@codethink.co.uk designates 176.9.8.82 as permitted sender) smtp.mailfrom=ben.hutchings@codethink.co.uk; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=codethink.co.uk Message-ID: <1520371350.23626.23.camel@codethink.co.uk> Subject: Re: [PATCH 4.4 03/34] mtd: nand: gpmi: Fix failure when a erased page has a bitflip at BBM From: Ben Hutchings To: Greg Kroah-Hartman , linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org, Sascha Hauer , Richard Weinberger , Boris Brezillon , Sasha Levin Date: Tue, 06 Mar 2018 21:22:30 +0000 In-Reply-To: <20180302084436.171257760@linuxfoundation.org> References: <20180302084435.842679610@linuxfoundation.org> <20180302084436.171257760@linuxfoundation.org> Organization: Codethink Ltd. Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.22.6-1+deb9u1 Mime-Version: 1.0 Content-Transfer-Encoding: 8bit X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1593815412959122192?= X-GMAIL-MSGID: =?utf-8?q?1594224911183387647?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: On Fri, 2018-03-02 at 09:50 +0100, Greg Kroah-Hartman wrote: > 4.4-stable review patch.  If anyone has any objections, please let me know. > > ------------------ > > From: Sascha Hauer > > > [ Upstream commit fdf2e821052958a114618a95ab18a300d0b080cb ] > > When erased subpages are read then the BCH decoder returns STATUS_ERASED > if they are all empty, or STATUS_UNCORRECTABLE if there are bitflips. > When there are bitflips, we have to set these bits again to show the > upper layers a completely erased page. When a bitflip happens in the > exact byte where the bad block marker is, then this byte is swapped > with another byte in block_mark_swapping(). The correction code then > detects a bitflip in another subpage and no longer corrects the bitflip > where it really happens. [...] This seesm to be a bug fix for commit bd2e778c9ee3 "gpmi-nand: Handle ECC Errors in erased pages". That's not in 4.4 so the bug fix is not needed, though it doesn't appear to do any harm. Ben. -- Ben Hutchings Software Developer, Codethink Ltd.