From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S937654AbdLRRsL (ORCPT ); Mon, 18 Dec 2017 12:48:11 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:36410 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934567AbdLRP5c (ORCPT ); Mon, 18 Dec 2017 10:57:32 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Liang Chen , Michael Lyle , Coly Li , Eric Wheeler , Jens Axboe , Sasha Levin Subject: [PATCH 4.4 093/115] bcache: explicitly destroy mutex while exiting Date: Mon, 18 Dec 2017 16:49:22 +0100 Message-Id: <20171218152859.013552923@linuxfoundation.org> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20171218152851.886086917@linuxfoundation.org> References: <20171218152851.886086917@linuxfoundation.org> User-Agent: quilt/0.65 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 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Liang Chen [ Upstream commit 330a4db89d39a6b43f36da16824eaa7a7509d34d ] mutex_destroy does nothing most of time, but it's better to call it to make the code future proof and it also has some meaning for like mutex debug. As Coly pointed out in a previous review, bcache_exit() may not be able to handle all the references properly if userspace registers cache and backing devices right before bch_debug_init runs and bch_debug_init failes later. So not exposing userspace interface until everything is ready to avoid that issue. Signed-off-by: Liang Chen Reviewed-by: Michael Lyle Reviewed-by: Coly Li Reviewed-by: Eric Wheeler Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/md/bcache/super.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -2083,6 +2083,7 @@ static void bcache_exit(void) if (bcache_major) unregister_blkdev(bcache_major, "bcache"); unregister_reboot_notifier(&reboot); + mutex_destroy(&bch_register_lock); } static int __init bcache_init(void) @@ -2101,14 +2102,15 @@ static int __init bcache_init(void) bcache_major = register_blkdev(0, "bcache"); if (bcache_major < 0) { unregister_reboot_notifier(&reboot); + mutex_destroy(&bch_register_lock); return bcache_major; } if (!(bcache_wq = create_workqueue("bcache")) || !(bcache_kobj = kobject_create_and_add("bcache", fs_kobj)) || - sysfs_create_files(bcache_kobj, files) || bch_request_init() || - bch_debug_init(bcache_kobj)) + bch_debug_init(bcache_kobj) || + sysfs_create_files(bcache_kobj, files)) goto err; return 0;