From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=0.6 required=3.0 tests=BIGNUM_EMAILS,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B00E9C3A59F for ; Mon, 26 Aug 2019 12:56:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8387F21852 for ; Mon, 26 Aug 2019 12:56:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="Gu3E8NFZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732083AbfHZM44 (ORCPT ); Mon, 26 Aug 2019 08:56:56 -0400 Received: from aserp2120.oracle.com ([141.146.126.78]:41392 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732082AbfHZM44 (ORCPT ); Mon, 26 Aug 2019 08:56:56 -0400 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x7QCsHCZ112399; Mon, 26 Aug 2019 12:56:52 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : mime-version : content-type; s=corp-2019-08-05; bh=evmC9BIm3CcBRO6yaMqxC7XnkfZ9l6H7T7ohzmil+oI=; b=Gu3E8NFZNGyshYhznI17dtqXYfVXJGKtCpzYHcPP8UGpKM4DWFVBL3svIonDR1o6xbe1 fhsb9NX+e1O4mjASL95cMCgcaXPx0IG9bH7o8XSHT2bmOo5amFaAPjjcoC2EapnQwnko +6WrX3XzQ1Fq7W3L7mPXp9PDQYZvfkajvsophnEnc2GMQ0irbv1+BM+JXE9kGjv7dfBj /K7NABrW1En9IhKPKqLrsMBlx28MwQnSPO4EBv78osvvp2aB4psG+cCYH8GSuFCgL+N6 SW5dhShAFV5XFrHcQPyzJn/wtL9SNo690WuTyDFfQRNJ6YQ3eudmjgMk3ZXT+7uE65ka Xw== Received: from userp3030.oracle.com (userp3030.oracle.com [156.151.31.80]) by aserp2120.oracle.com with ESMTP id 2ujw700wtn-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 26 Aug 2019 12:56:52 +0000 Received: from pps.filterd (userp3030.oracle.com [127.0.0.1]) by userp3030.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x7QCsHhS114229; Mon, 26 Aug 2019 12:56:52 GMT Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by userp3030.oracle.com with ESMTP id 2ujw6cad08-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 26 Aug 2019 12:56:51 +0000 Received: from abhmp0016.oracle.com (abhmp0016.oracle.com [141.146.116.22]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id x7QCup8j027804; Mon, 26 Aug 2019 12:56:51 GMT Received: from mwanda (/41.57.98.10) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Mon, 26 Aug 2019 05:56:50 -0700 Date: Mon, 26 Aug 2019 15:56:45 +0300 From: Dan Carpenter To: eranbe@mellanox.com Cc: linux-rdma@vger.kernel.org Subject: [bug report] net/mlx5e: Add mlx5e HV VHCA stats agent Message-ID: <20190826125645.GA32067@mwanda> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.10.1 (2018-07-13) X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9360 signatures=668684 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=1 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=873 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1906280000 definitions=main-1908260140 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9360 signatures=668684 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1011 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=936 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1906280000 definitions=main-1908260140 Sender: linux-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org Hello Eran Ben Elisha, The patch cef35af34d6d: "net/mlx5e: Add mlx5e HV VHCA stats agent" from Aug 22, 2019, leads to the following static checker warning: drivers/net/ethernet/mellanox/mlx5/core/en/hv_vhca_stats.c:41 mlx5e_hv_vhca_fill_stats() warn: potential pointer math issue ('buf' is a u64 pointer) drivers/net/ethernet/mellanox/mlx5/core/en/hv_vhca_stats.c 33 static void mlx5e_hv_vhca_fill_stats(struct mlx5e_priv *priv, u64 *data, ^^^^^^^^^ data is a u64 pointer. 34 int buf_len) 35 { 36 int ch, i = 0; 37 38 for (ch = 0; ch < priv->max_nch; ch++) { 39 u64 *buf = data + i; ^^^^^^^^ 40 41 if (WARN_ON_ONCE(buf + 42 sizeof(struct mlx5e_hv_vhca_per_ring_stats) > ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ This pointer math doesn't work. I'm surprised the warning doesn't trigger. 43 data + buf_len)) 44 return; 45 46 mlx5e_hv_vhca_fill_ring_stats(priv, ch, 47 (struct mlx5e_hv_vhca_per_ring_stats *)buf); ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ If we made both "data" and "buf" void pointers then this would be much easier and the casting could be removed. 48 i += sizeof(struct mlx5e_hv_vhca_per_ring_stats) / sizeof(u64); ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ This math works, but it's so complicated and you have to verify that mlx5e_hv_vhca_per_ring_stats % sizeof(u64) is zero. 49 } 50 } regards, dan carpenter