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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham 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 528CEC28CF8 for ; Tue, 20 Nov 2018 15:23:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C4BF820831 for ; Tue, 20 Nov 2018 15:23:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C4BF820831 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-nfs-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728019AbeKUBwi (ORCPT ); Tue, 20 Nov 2018 20:52:38 -0500 Received: from mga05.intel.com ([192.55.52.43]:24294 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726108AbeKUBwi (ORCPT ); Tue, 20 Nov 2018 20:52:38 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga105.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 20 Nov 2018 07:22:59 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,257,1539673200"; d="scan'208";a="93525854" Received: from ddalessa-mobl2.amr.corp.intel.com (HELO [10.254.201.218]) ([10.254.201.218]) by orsmga008.jf.intel.com with ESMTP; 20 Nov 2018 07:22:57 -0800 Subject: Re: [PATCH v1 1/4] xprtrdma: Remove support for FMR memory registration To: Jason Gunthorpe , Bart Van Assche Cc: Chuck Lever , linux-rdma@vger.kernel.org, linux-nfs@vger.kernel.org, oulijun@huawei.com, umalhi@cisco.com, zhongjiang@huawei.com, venkata.s.dhanalakota@intel.com References: <20181119153707.10832.42881.stgit@manet.1015granger.net> <20181119154551.10832.5498.stgit@manet.1015granger.net> <1542644197.185366.50.camel@acm.org> <20181119224143.GL4890@ziepe.ca> From: Dennis Dalessandro Message-ID: Date: Tue, 20 Nov 2018 10:22:56 -0500 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.3.0 MIME-Version: 1.0 In-Reply-To: <20181119224143.GL4890@ziepe.ca> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org On 11/19/2018 5:41 PM, Jason Gunthorpe wrote: > On Mon, Nov 19, 2018 at 08:16:37AM -0800, Bart Van Assche wrote: >> On Mon, 2018-11-19 at 10:45 -0500, Chuck Lever wrote: >>> FMR is not supported on most recent RDMA devices. It is also slower >>> and less secure than FRWR. As discussed during the RDMA BoF at LPC >>> 2018, it is time to remove support for FMR in the NFS/RDMA client >>> stack. NFS/RDMA server-side uses either local memory registration or >>> FRWR. There is no change required there to deprecate FMR. >>> >>> There are a few Infiniband/RoCE devices in the kernel tree that do >>> not support MEM_MGT_EXTENSIONS, and therefore will no longer support >>> client-side NFS/RDMA. These are: >>> >>> - mthca >>> - qib > > Ooh, qib was not in the list when we talked on this in plumbers. That > does change things. > > Dennis: Could qib be changed? HFI1 supports FRWR right? Turns out that qib can not support FRWR because that requires HW support for opcodes that qib just doesn't understand. hfi1 is good to go though. >>> - usnic >>> - hns (RoCE) >> >> Can someone from Intel comment on how many of their customers rely on the qib >> driver? There is a user base. I can't say how large though. But I have had discussions with mgmt and we aren't quite ready to leave qib out in the cold just yet. We have a lot of people out this week due to the US Thanksgiving holiday. Once people are back in the office on Monday I'll find out some more as to the impact of this change. -Denny