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=-4.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 265D8C433E1 for ; Fri, 24 Jul 2020 14:18:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F3C8B21883 for ; Fri, 24 Jul 2020 14:18:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=ziepe.ca header.i=@ziepe.ca header.b="CbVcBajo" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726593AbgGXOSr (ORCPT ); Fri, 24 Jul 2020 10:18:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45306 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726317AbgGXOSr (ORCPT ); Fri, 24 Jul 2020 10:18:47 -0400 Received: from mail-io1-xd41.google.com (mail-io1-xd41.google.com [IPv6:2607:f8b0:4864:20::d41]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 07316C0619D3 for ; Fri, 24 Jul 2020 07:18:47 -0700 (PDT) Received: by mail-io1-xd41.google.com with SMTP id l17so9930694iok.7 for ; Fri, 24 Jul 2020 07:18:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to; bh=97Eau43xA83rlvFNofyvOIXATD23u4GkUBeWbIi3frM=; b=CbVcBajoW5NC1gRhXLGuo4cbkocuJAcx6sbTAYsD9zO0iKlvfdGgMrX09AZY3u4pbT FxxkoAKPDQ7EIxnNKk8bGNQSRLdYdGLhgaYsa49ENEDnmTx6WIza4rVSB/prfADOhKJl 35egjCCLr/I5haRObW5eYPT+1NVuOZLCb40V/wBN4zWefIZmkXx5ASrmh2lsniKV0yct Lfb1g2T92CZySnXZAUSyTiIh2U7qxWi7pGv55jF4G8Q696U7GG6/r5P8BeehJhTH2t2F eQO5NXhCxQ/AVssZmqqpCdS2DvzE8z1NpJgGWmZ3FKOnvvDvCDgKjAEErc6nJ7no5nTJ q7Ew== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to; bh=97Eau43xA83rlvFNofyvOIXATD23u4GkUBeWbIi3frM=; b=IByl7DMSS7MZUwfWDEkacm7H6LXAK1VTqH/vafL9rp59LwulGnujRR2eobOzj2W2y7 Gn1DGaihjXANKsExYLn2DGyDfBRSQ4jvoFzGASisN2DBsMFOeqOYtWCfakxgSQU6j4eX O/ypeDCEys0LgqDQ7jx53hA3nUhaCuFcA7FEkI7vd7uJRTMezxvChJm6FDsFZlgCqQpq HQp89yu2/WRboUppqNfqXnSes8pzfDI5lGYmmNl3bhijlOzicM+1GOHvLyWBcZjJ6JSY E/lN0zZWkKDYBSkyAgI2P+BbRNJpIiinsfjlbz1IfK5eCLuiI+B1OOLUvzcapYUJ3sQy usJQ== X-Gm-Message-State: AOAM532J7Mx9JOTLUcPDgk1W3e59Du/YwpiXU5e+uLZagp7CYk9fUc+E 2AkTXOuMaUL3A9qqzV8gC16mgA== X-Google-Smtp-Source: ABdhPJx1NqHOd+CL2UZG4FKWDIBoKooU3hYZM4+wB1xhrb/6gSFPYasbisTr+FpcneUtQBeZZHF4xA== X-Received: by 2002:a5d:8510:: with SMTP id q16mr10604066ion.81.1595600326357; Fri, 24 Jul 2020 07:18:46 -0700 (PDT) Received: from ziepe.ca (hlfxns017vw-156-34-48-30.dhcp-dynamic.fibreop.ns.bellaliant.net. [156.34.48.30]) by smtp.gmail.com with ESMTPSA id p9sm3327999ilc.78.2020.07.24.07.18.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 24 Jul 2020 07:18:45 -0700 (PDT) Received: from jgg by mlx with local (Exim 4.94) (envelope-from ) id 1jyyX6-00F4mp-J6; Fri, 24 Jul 2020 11:18:44 -0300 Date: Fri, 24 Jul 2020 11:18:44 -0300 From: Jason Gunthorpe To: =?utf-8?B?5p2o5biG?= Cc: Zhu Yanjun , Zhu Yanjun , linux-rdma@vger.kernel.org Subject: Re: [External] [PATCH] RDMA/rxe: fix retry forever when rnr_retry >= 7 Message-ID: <20200724141844.GO25301@ziepe.ca> References: <827596D2-8EB2-4660-9118-70289FCD09AA@bytedance.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <827596D2-8EB2-4660-9118-70289FCD09AA@bytedance.com> Sender: linux-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Fri, Jul 24, 2020 at 10:04:01PM +0800, 杨帆 wrote: > > > > Please read the following from IB specification > > > > Oh I see, I missed that part. Thanks for your explanation. > > > > An exception to > > the following is if the RNR NAK retry counter is set to 7. This value indicates > > infinite retry and the counter is not decremented. > > I wonder what if the user set RNR retry larger than 7? Say the user set the RNR > retry attribute to 10, is he expecting a 10-time retry or an infinite retry? In > the current implementation, any larger-than-7 retry count causes infinite retry. > Is this an expected behavior? Out of range values should be rejected at modify_qp time Jason