From patchwork Thu Sep 8 03:04:19 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Ziyang Xuan (William)" X-Patchwork-Id: 12969593 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4053DC6FA86 for ; Thu, 8 Sep 2022 03:04:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229913AbiIHDEk (ORCPT ); Wed, 7 Sep 2022 23:04:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42822 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229583AbiIHDEg (ORCPT ); Wed, 7 Sep 2022 23:04:36 -0400 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1B6C33887; Wed, 7 Sep 2022 20:04:28 -0700 (PDT) Received: from canpemm500006.china.huawei.com (unknown [172.30.72.57]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4MNP6R70hLzgYv0; Thu, 8 Sep 2022 11:01:51 +0800 (CST) Received: from localhost.localdomain (10.175.104.82) by canpemm500006.china.huawei.com (7.192.105.130) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Thu, 8 Sep 2022 11:04:26 +0800 From: Ziyang Xuan To: , , , , , CC: Subject: [PATCH 1/2] can: bcm: registration process optimization in bcm_module_init() Date: Thu, 8 Sep 2022 11:04:19 +0800 Message-ID: <823cff0ebec33fa9389eeaf8b8ded3217c32cb38.1662606045.git.william.xuanziyang@huawei.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 X-Originating-IP: [10.175.104.82] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To canpemm500006.china.huawei.com (7.192.105.130) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org Now, register_netdevice_notifier() and register_pernet_subsys() are both after can_proto_register(). It can create CAN_BCM socket and process socket once can_proto_register() successfully, so it is possible missing notifier event or proc node creation because notifier or bcm proc directory is not registered or created yet. Although this is a low probability scenario, it is not impossible. Move register_pernet_subsys() and register_netdevice_notifier() to the front of can_proto_register(). In addition, register_pernet_subsys() and register_netdevice_notifier() may fail, check their results are necessary. Signed-off-by: Ziyang Xuan --- net/can/bcm.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/net/can/bcm.c b/net/can/bcm.c index e60161bec850..e2783156bfd1 100644 --- a/net/can/bcm.c +++ b/net/can/bcm.c @@ -1744,15 +1744,27 @@ static int __init bcm_module_init(void) pr_info("can: broadcast manager protocol\n"); + err = register_pernet_subsys(&canbcm_pernet_ops); + if (err) + return err; + + err = register_netdevice_notifier(&canbcm_notifier); + if (err) + goto register_notifier_failed; + err = can_proto_register(&bcm_can_proto); if (err < 0) { printk(KERN_ERR "can: registration of bcm protocol failed\n"); - return err; + goto register_proto_failed; } - register_pernet_subsys(&canbcm_pernet_ops); - register_netdevice_notifier(&canbcm_notifier); return 0; + +register_proto_failed: + unregister_netdevice_notifier(&canbcm_notifier); +register_notifier_failed: + unregister_pernet_subsys(&canbcm_pernet_ops); + return err; } static void __exit bcm_module_exit(void)