From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751121AbeAUQnW (ORCPT ); Sun, 21 Jan 2018 11:43:22 -0500 Received: from mail-pg0-f43.google.com ([74.125.83.43]:39002 "EHLO mail-pg0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750825AbeAUQnV (ORCPT ); Sun, 21 Jan 2018 11:43:21 -0500 X-Google-Smtp-Source: AH8x224O8G4tlFbxN4Zur/cCl9gHU9MlKWuLGEn0Yn2YkLv7fb5Jyu3jFa3Cdr1ZQrj0F6iBI3Np+w== Message-ID: <1516552998.3478.5.camel@gmail.com> Subject: Re: [PATCH] net/mlx4_en: ensure rx_desc updating reaches HW before prod db updating From: Eric Dumazet To: Tariq Toukan , "jianchao.wang" , Jason Gunthorpe Cc: junxiao.bi@oracle.com, netdev@vger.kernel.org, linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org, Saeed Mahameed Date: Sun, 21 Jan 2018 08:43:18 -0800 In-Reply-To: <339a7156-9ef1-1f3c-30b8-3cc3558d124e@mellanox.com> References: <1515728542-3060-1-git-send-email-jianchao.w.wang@oracle.com> <339a7156-9ef1-1f3c-30b8-3cc3558d124e@mellanox.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.22.6-1+deb9u1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 2018-01-21 at 18:24 +0200, Tariq Toukan wrote: > > On 21/01/2018 11:31 AM, Tariq Toukan wrote: > > > > > > On 19/01/2018 5:49 PM, Eric Dumazet wrote: > > > On Fri, 2018-01-19 at 23:16 +0800, jianchao.wang wrote: > > > > Hi Tariq > > > > > > > > Very sad that the crash was reproduced again after applied the patch. > > Memory barriers vary for different Archs, can you please share more > details regarding arch and repro steps? Yeah, mlx4 NICs in Google fleet receive trillions of packets per second, and we never noticed an issue. Although we are using a slightly different driver, using order-0 pages and fast pages recycling.