Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760089AbaJCX1Y (ORCPT ); Fri, 3 Oct 2014 19:27:24 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:46292 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757409AbaJCWD7 (ORCPT ); Fri, 3 Oct 2014 18:03:59 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, NeilBrown Subject: [PATCH 3.16 333/357] md/raid1: update next_resync under resync_lock. Date: Fri, 3 Oct 2014 14:31:59 -0700 Message-Id: <20141003212943.461151084@linuxfoundation.org> X-Mailer: git-send-email 2.1.2 In-Reply-To: <20141003212933.458851516@linuxfoundation.org> References: <20141003212933.458851516@linuxfoundation.org> User-Agent: quilt/0.63-1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: NeilBrown commit c2fd4c94deedb89ac1746c4a53219be499372c06 upstream. raise_barrier() uses next_resync as part of its calculations, so it really should be updated first, instead of afterwards. next_resync is always used under resync_lock so update it under resync lock to, just before it is used. That is safest. This could cause normal IO and resync IO to interact badly so it suitable for -stable. Fixes: 79ef3a8aa1cb1523cc231c9a90a278333c21f761 Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman --- drivers/md/raid1.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -827,7 +827,7 @@ static void flush_pending_writes(struct * there is no normal IO happeing. It must arrange to call * lower_barrier when the particular background IO completes. */ -static void raise_barrier(struct r1conf *conf) +static void raise_barrier(struct r1conf *conf, sector_t sector_nr) { spin_lock_irq(&conf->resync_lock); @@ -837,6 +837,7 @@ static void raise_barrier(struct r1conf /* block any new IO from starting */ conf->barrier++; + conf->next_resync = sector_nr; /* For these conditions we must wait: * A: while the array is in frozen state @@ -2542,9 +2543,8 @@ static sector_t sync_request(struct mdde bitmap_cond_end_sync(mddev->bitmap, sector_nr); r1_bio = mempool_alloc(conf->r1buf_pool, GFP_NOIO); - raise_barrier(conf); - conf->next_resync = sector_nr; + raise_barrier(conf, sector_nr); rcu_read_lock(); /* -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/