From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754805AbeANCkY (ORCPT + 1 other); Sat, 13 Jan 2018 21:40:24 -0500 Received: from userp2130.oracle.com ([156.151.31.86]:46692 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750866AbeANCkW (ORCPT ); Sat, 13 Jan 2018 21:40:22 -0500 Subject: Re: [PATCH] net/mlx4_en: ensure rx_desc updating reaches HW before prod db updating To: Eric Dumazet , Jason Gunthorpe Cc: tariqt@mellanox.com, junxiao.bi@oracle.com, netdev@vger.kernel.org, linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org, Saeed Mahameed References: <1515728542-3060-1-git-send-email-jianchao.w.wang@oracle.com> <20180112163247.GB15974@ziepe.ca> <1515775567.131759.42.camel@gmail.com> From: "jianchao.wang" Message-ID: Date: Sun, 14 Jan 2018 10:40:10 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.5.0 MIME-Version: 1.0 In-Reply-To: <1515775567.131759.42.camel@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=8773 signatures=668652 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=887 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1711220000 definitions=main-1801140035 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: Dear all Thanks for the kindly response and reviewing. That's really appreciated. On 01/13/2018 12:46 AM, Eric Dumazet wrote: >> Does this need to be dma_wmb(), and should it be in >> mlx4_en_update_rx_prod_db ? >> > +1 on dma_wmb() > > On what architecture bug was observed ? This issue was observed on x86-64. And I will send a new patch, in which replace wmb() with dma_wmb(), to customer to confirm. Thanks Jianchao