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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 3576EC433E0 for ; Sun, 24 May 2020 01:27:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 15D5A20759 for ; Sun, 24 May 2020 01:27:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387589AbgEXB1y (ORCPT ); Sat, 23 May 2020 21:27:54 -0400 Received: from p3plsmtpa11-04.prod.phx3.secureserver.net ([68.178.252.105]:41711 "EHLO p3plsmtpa11-04.prod.phx3.secureserver.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726849AbgEXB1y (ORCPT ); Sat, 23 May 2020 21:27:54 -0400 Received: from [192.168.0.78] ([24.218.182.144]) by :SMTPAUTH: with ESMTPSA id cfQcjZA3RwSzlcfQcjhtVl; Sat, 23 May 2020 18:27:51 -0700 X-CMAE-Analysis: v=2.3 cv=PMNxBsiC c=1 sm=1 tr=0 a=ugQcCzLIhEHbLaAUV45L0A==:117 a=ugQcCzLIhEHbLaAUV45L0A==:17 a=IkcTkHD0fZMA:10 a=BCZ4t0ovHPUC9Q3tnhUA:9 a=QEXdDO2ut3YA:10 X-SECURESERVER-ACCT: tom@talpey.com Subject: Re: [PATCH 0/8 v1] Remove FMR support from RDMA drivers To: Jason Gunthorpe , Dennis Dalessandro Cc: Leon Romanovsky , Max Gurtovoy , bvanassche@acm.org, linux-rdma@vger.kernel.org, dledford@redhat.com, sagi@grimberg.me, israelr@mellanox.com, shlomin@mellanox.com, "Marciniszyn, Mike" References: <20200514120305.189738-1-maxg@mellanox.com> <20200518181035.GM24561@mellanox.com> <03238a7d-d3f3-7859-deb9-dd0a04fbe9ed@intel.com> <20200519135352.GV24561@mellanox.com> <20200519141927.GR188135@unreal> <774b4d00-ab2e-6f1a-eaa6-a7afadc3c44d@intel.com> <20200519143030.GA23839@mellanox.com> <5563b8da-faf3-1af5-33d0-fe5a6d7291a1@intel.com> <20200523220821.GB744@ziepe.ca> From: Tom Talpey Message-ID: <94aca558-442a-c37e-f0c4-e000813721cb@talpey.com> Date: Sat, 23 May 2020 21:27:50 -0400 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 MIME-Version: 1.0 In-Reply-To: <20200523220821.GB744@ziepe.ca> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-CMAE-Envelope: MS4wfHsAAia/Ot3DGQij5OEoDvum4illJf2qpmI7BP/9o+wUNPda26hR65MjZaMBLn5/h5S4K+w3l3nBjjn40KXnBGkU7lsGxEtY/M/+HSkdAGYFe5vbpZGk 1ofhIh45jnOOh+HM9bB9YM7K/1/KWFg9sSqX+5R1YX8HOUBes+RcdsQaKkW+rtZi4gAKiKKDjWXehnIT98GeJW6sNCxG1DqlbwFLaZG3QYnbKbbmx2T0hqdY RRZlIDqyJYL7YVu4mUD4v+TfKhmblnr1ztD40CJeI12JAgiC+NaDCnFHY2FL0aXjZ5oBWefnWV9SFP3vH8NEtwN1S4xE46HlLALYqgP1vgdH4Ry0Dp86Ye4v MlkeQMZGGTAJmmH6z30Ug/OiPv8WJSjX6DulvrM5b0JsgBhIkBOZflzixDhbsFcZDUFr02+6U23mf7g6tnYFYDOIDLuSJhY1BTtCbx9f0RyZZpQrHtMgEpbh ePpN1Vh6B8kFyhxU Sender: linux-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On 5/23/2020 6:08 PM, Jason Gunthorpe wrote: > On Tue, May 19, 2020 at 10:37:07AM -0400, Dennis Dalessandro wrote: >> On 5/19/2020 10:30 AM, Jason Gunthorpe wrote: >>> On Tue, May 19, 2020 at 10:26:37AM -0400, Dennis Dalessandro wrote: >>>> On 5/19/2020 10:19 AM, Leon Romanovsky wrote: >>>>> On Tue, May 19, 2020 at 10:53:52AM -0300, Jason Gunthorpe wrote: >>>>>> On Tue, May 19, 2020 at 09:43:14AM -0400, Dennis Dalessandro wrote: >>>>>>> On 5/18/2020 2:10 PM, Jason Gunthorpe wrote: >>>>>>>> On Mon, May 18, 2020 at 11:20:04AM -0400, Dennis Dalessandro wrote: >>>>>>>>> On 5/14/2020 8:02 AM, Max Gurtovoy wrote: >>>>>>>>>> This series removes the support for FMR mode to register memory. This ancient >>>>>>>>>> mode is unsafe and not maintained/tested in the last few years. It also doesn't >>>>>>>>>> have any reasonable advantage over other memory registration methods such as >>>>>>>>>> FRWR (that is implemented in all the recent RDMA adapters). This series should >>>>>>>>>> be reviewed and approved by the maintainer of the effected drivers and I >>>>>>>>>> suggest to test it as well. >>>>>>>>>> >>>>>>>>>> The tests that I made for this series (fio benchmarks and fio verify data): >>>>>>>>>> 1. iSER initiator on ConnectX-4 >>>>>>>>>> 2. iSER initiator on ConnectX-3 >>>>>>>>>> 3. SRP initiator on ConnectX-4 (loopback to SRP target) >>>>>>>>>> 4. SRP initiator on ConnectX-3 >>>>>>>>>> >>>>>>>>>> Not tested: >>>>>>>>>> 1. RDS >>>>>>>>>> 2. mthca >>>>>>>>>> 3. rdmavt >>>>>>>>> >>>>>>>>> This will effectively kill qib which uses rdmavt. It's gonna have to be a >>>>>>>>> NAK from me. >>>>>>>> >>>>>>>> Are you objecting the SRP and iSER changes too? >>>>>>> >>>>>>> No, just want to keep basic verbs support at least. NFS already dropped, >>>>>>> similarly we are ok with dropping it from SRP/iSER as a next step. >>>>>> >>>>>> So you see a major user in RDS for qib? >>>>> >>>>> Didn't we agree to drop it from RDS too? >>>>> >>>> >>>> Just basic verbs application support is enough for qib I think. I don't see >>>> any major use of RDS. >>> >>> Well, once the in-kernel users of an API are gone that API will be >>> purged. This is standard kernel policy. >>> >>> So you can't NAK this series on the grounds you want to keep an API >>> without users, presumably for out of tree modules... >>> >> >> Maybe I need to look at this again. I thought it would kill off user access >> as well. We don't need any kernel ULPs. > > Did you make a conclusion? Seems like everyone else is in agreement > here, if Max resends a v2 I'm inclined to take it unless RDS objects. > > I did not think FMR or FRWR were available from userspace at all. I certainly hope they're not available from userspace, as they both take physaddrs to reference memory! Tom.