From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io0-f169.google.com ([209.85.223.169]:38115 "EHLO mail-io0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932086AbdK0RBo (ORCPT ); Mon, 27 Nov 2017 12:01:44 -0500 Received: by mail-io0-f169.google.com with SMTP id h205so36310844iof.5 for ; Mon, 27 Nov 2017 09:01:44 -0800 (PST) Subject: Re: Patch "bcache: only permit to recovery read error when cache device is clean" has been added to the 4.9-stable tree To: Eddie Chapman , gregkh@linuxfoundation.org, colyli@suse.de, mlyle@lyle.org Cc: awolf@lenovo.com, bcache@lists.ewheeler.net, hurikhan77@gmail.com, kent.overstreet@gmail.com, nix@esperi.org.uk, tang.junhui@zte.com.cn, stable@vger.kernel.org References: <1511798800229104@kroah.com> <704d1c65-b032-314b-3ad1-e87229dc655a@ehuk.net> From: Jens Axboe Message-ID: <2bc54d3d-0fbe-0e8e-97b5-a317972d0ad3@kernel.dk> Date: Mon, 27 Nov 2017 10:01:41 -0700 MIME-Version: 1.0 In-Reply-To: <704d1c65-b032-314b-3ad1-e87229dc655a@ehuk.net> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: stable-owner@vger.kernel.org List-ID: On 11/27/2017 09:45 AM, Eddie Chapman wrote: > On 27/11/17 16:06, gregkh@linuxfoundation.org wrote: >> >> This is a note to let you know that I've just added the patch titled >> >> bcache: only permit to recovery read error when cache device is clean >> >> to the 4.9-stable tree which can be found at: >> http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary >> >> The filename of the patch is: >> bcache-only-permit-to-recovery-read-error-when-cache-device-is-clean.patch >> and it can be found in the queue-4.9 subdirectory. >> >> If you, or anyone else, feels it should not be added to the stable tree, >> please let know about it. > > Hi Greg, > > This patch is an important fix for a possible data corruption issue, but > it also introduces a bug that can produce read errors under certain > circumstances. The issue introduced by this patch is not as severe as > the issue it fixes, but can lead to e.g. upper layer fs remounting read > only. In my environment upper layer handled it badly and indirectly > resulted in data loss (not directly bcache's fault of course). > > Michael Lyle CC'd the stable list with a follow up fix for the issue > introduced by this patch, on 24th Nov, subject "bcache: recover data > from backing when data is clean". > > However, the followup fix is not in Linus' tree yet, only in Michael's. > I guess that means you can't pick it up yet. Never-the-less I felt it > important to point this out here. It's commit e393aa2446150536929140739f09c6ecbcbea7f0 in my tree and will go upstream shortly - but yes, probably should not add this one, before both can be pulled in. -- Jens Axboe