From patchwork Mon Aug 14 07:23:42 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Li Zetao X-Patchwork-Id: 13352445 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 E6044C04A94 for ; Mon, 14 Aug 2023 07:24:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231357AbjHNHYX (ORCPT ); Mon, 14 Aug 2023 03:24:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42444 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232796AbjHNHYJ (ORCPT ); Mon, 14 Aug 2023 03:24:09 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5A0E0E73; Mon, 14 Aug 2023 00:24:08 -0700 (PDT) Received: from kwepemi500012.china.huawei.com (unknown [172.30.72.54]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4RPQm01tnyzNnMy; Mon, 14 Aug 2023 15:20:32 +0800 (CST) Received: from huawei.com (10.90.53.73) by kwepemi500012.china.huawei.com (7.221.188.12) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Mon, 14 Aug 2023 15:24:02 +0800 From: Li Zetao To: CC: , , , , , , , , , , , , , , kernel test robot , Dan Carpenter Subject: [PATCH -next v2] net/mlx5: Devcom, only use devcom after NULL check in mlx5_devcom_send_event() Date: Mon, 14 Aug 2023 15:23:42 +0800 Message-ID: <20230814072342.189470-1-lizetao1@huawei.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: References: MIME-Version: 1.0 X-Originating-IP: [10.90.53.73] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To kwepemi500012.china.huawei.com (7.221.188.12) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org There is a warning reported by kernel test robot: smatch warnings: drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c:264 mlx5_devcom_send_event() warn: variable dereferenced before IS_ERR check devcom (see line 259) The reason for the warning is that the pointer is used before check, put the assignment to comp after devcom check to silence the warning. Fixes: 88d162b47981 ("net/mlx5: Devcom, Infrastructure changes") Reported-by: kernel test robot Reported-by: Dan Carpenter Closes: https://lore.kernel.org/r/202308041028.AkXYDwJ6-lkp@intel.com/ Signed-off-by: Li Zetao Reviewed-by: Leon Romanovsky --- v1 -> v2: Modify the order of variable declarations to end up with reverse x-mas tree order. v1: https://lore.kernel.org/all/20230804092636.91357-1-lizetao1@huawei.com/ drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c b/drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c index feb62d952643..00e67910e3ee 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c @@ -256,14 +256,15 @@ int mlx5_devcom_send_event(struct mlx5_devcom_comp_dev *devcom, int event, int rollback_event, void *event_data) { - struct mlx5_devcom_comp *comp = devcom->comp; struct mlx5_devcom_comp_dev *pos; + struct mlx5_devcom_comp *comp; int err = 0; void *data; if (IS_ERR_OR_NULL(devcom)) return -ENODEV; + comp = devcom->comp; down_write(&comp->sem); list_for_each_entry(pos, &comp->comp_dev_list_head, list) { data = rcu_dereference_protected(pos->data, lockdep_is_held(&comp->sem));