From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:52556 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753164AbbIZR0e (ORCPT ); Sat, 26 Sep 2015 13:26:34 -0400 Subject: Patch "md/raid10: always set reshape_safe when initializing reshape_position." has been added to the 4.1-stable tree To: neilb@suse.com, gregkh@linuxfoundation.org Cc: , From: Date: Sat, 26 Sep 2015 10:26:34 -0700 Message-ID: <1443288394251161@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled md/raid10: always set reshape_safe when initializing reshape_position. to the 4.1-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: md-raid10-always-set-reshape_safe-when-initializing-reshape_position.patch and it can be found in the queue-4.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 299b0685e31c9f3dcc2d58ee3beca761a40b44b3 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Mon, 6 Jul 2015 17:37:49 +1000 Subject: md/raid10: always set reshape_safe when initializing reshape_position. From: NeilBrown commit 299b0685e31c9f3dcc2d58ee3beca761a40b44b3 upstream. 'reshape_position' tracks where in the reshape we have reached. 'reshape_safe' tracks where in the reshape we have safely recorded in the metadata. These are compared to determine when to update the metadata. So it is important that reshape_safe is initialised properly. Currently it isn't. When starting a reshape from the beginning it usually has the correct value by luck. But when reducing the number of devices in a RAID10, it has the wrong value and this leads to the metadata not being updated correctly. This can lead to corruption if the reshape is not allowed to complete. This patch is suitable for any -stable kernel which supports RAID10 reshape, which is 3.5 and later. Fixes: 3ea7daa5d7fd ("md/raid10: add reshape support") Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman --- drivers/md/raid10.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -3566,6 +3566,7 @@ static struct r10conf *setup_conf(struct /* far_copies must be 1 */ conf->prev.stride = conf->dev_sectors; } + conf->reshape_safe = conf->reshape_progress; spin_lock_init(&conf->device_lock); INIT_LIST_HEAD(&conf->retry_list); @@ -3770,7 +3771,6 @@ static int run(struct mddev *mddev) } conf->offset_diff = min_offset_diff; - conf->reshape_safe = conf->reshape_progress; clear_bit(MD_RECOVERY_SYNC, &mddev->recovery); clear_bit(MD_RECOVERY_CHECK, &mddev->recovery); set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery); @@ -4113,6 +4113,7 @@ static int raid10_start_reshape(struct m conf->reshape_progress = size; } else conf->reshape_progress = 0; + conf->reshape_safe = conf->reshape_progress; spin_unlock_irq(&conf->device_lock); if (mddev->delta_disks && mddev->bitmap) { @@ -4180,6 +4181,7 @@ abort: rdev->new_data_offset = rdev->data_offset; smp_wmb(); conf->reshape_progress = MaxSector; + conf->reshape_safe = MaxSector; mddev->reshape_position = MaxSector; spin_unlock_irq(&conf->device_lock); return ret; @@ -4534,6 +4536,7 @@ static void end_reshape(struct r10conf * md_finish_reshape(conf->mddev); smp_wmb(); conf->reshape_progress = MaxSector; + conf->reshape_safe = MaxSector; spin_unlock_irq(&conf->device_lock); /* read-ahead size must cover two whole stripes, which is Patches currently in stable-queue which might be from neilb@suse.com are queue-4.1/md-raid5-avoid-races-when-changing-cache-size.patch queue-4.1/md-flush-event_work-before-stopping-array.patch queue-4.1/md-raid5-don-t-let-shrink_slab-shrink-too-far.patch queue-4.1/nfsv4-don-t-set-setattr-for-o_rdonly-o_excl.patch queue-4.1/md-raid10-always-set-reshape_safe-when-initializing-reshape_position.patch