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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4E533C433FE for ; Sat, 25 Dec 2021 00:03:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231766AbhLYADY (ORCPT ); Fri, 24 Dec 2021 19:03:24 -0500 Received: from out0.migadu.com ([94.23.1.103]:10567 "EHLO out0.migadu.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230052AbhLYADX (ORCPT ); Fri, 24 Dec 2021 19:03:23 -0500 Message-ID: <3d08b270-367e-e01d-a095-85309f8c1f7f@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1640390599; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=+aRu7ZV32gPZhDZHGEcScWPJuNorY5WXOAj2wCLAD9Q=; b=Loi60gic5EMFPX48WzmfY+zNktegY7oS/mbeBU/sQoBr39pEu3cBCPtvkBzLUKDlVyQ6NH xhaoAa8wO8uMI3EX4unLWUdHpAEdajkVWj+cLKAsLAhw1ODepwaPea/crjXGBHtAmcakb2 2mHMc45Ho5jRVpu9NT9GiULbUNu2X1o= Date: Sat, 25 Dec 2021 08:03:11 +0800 MIME-Version: 1.0 Subject: Re: [PATCH rdma-next 10/11] RDMA/erdma: Add the ABI definitions To: Leon Romanovsky , Cheng Xu Cc: jgg@ziepe.ca, dledford@redhat.com, linux-rdma@vger.kernel.org, KaiShen@linux.alibaba.com, tonylu@linux.alibaba.com References: <20211221024858.25938-1-chengyou@linux.alibaba.com> <20211221024858.25938-11-chengyou@linux.alibaba.com> <6cb90490-d21c-e76e-19b9-2a7fe0669e04@linux.dev> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Yanjun Zhu In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: linux.dev Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org 在 2021/12/25 2:19, Leon Romanovsky 写道: > On Fri, Dec 24, 2021 at 03:12:35PM +0800, Cheng Xu wrote: >> >> On 12/24/21 6:55 AM, Yanjun Zhu wrote: >>> 在 2021/12/24 2:45, Leon Romanovsky 写道: >>>> On Thu, Dec 23, 2021 at 11:46:03PM +0800, Yanjun Zhu wrote: >>>>> 在 2021/12/21 10:48, Cheng Xu 写道: >>>>>> Signed-off-by: Cheng Xu >>>>>> --- >>>>>>    include/uapi/rdma/erdma-abi.h | 49 >>>>>> +++++++++++++++++++++++++++++++++++ >>>>>>    1 file changed, 49 insertions(+) >>>>>>    create mode 100644 include/uapi/rdma/erdma-abi.h >>>>>> >>>>>> diff --git a/include/uapi/rdma/erdma-abi.h >>>>>> b/include/uapi/rdma/erdma-abi.h >>>>>> new file mode 100644 >>>>>> index 000000000000..6bcba10c1e41 >>>>>> --- /dev/null >>>>>> +++ b/include/uapi/rdma/erdma-abi.h >>>>>> @@ -0,0 +1,49 @@ >>>>>> +/* SPDX-License-Identifier: ((GPL-2.0 WITH >>>>>> Linux-syscall-note) OR Linux-OpenIB) */ >>>>>> +/* >>>>>> + * Copyright (c) 2020-2021, Alibaba Group. >>>>>> + */ >>>>>> + >>>>>> +#ifndef __ERDMA_USER_H__ >>>>>> +#define __ERDMA_USER_H__ >>>>>> + >>>>>> +#include >>>>>> + >>>>>> +#define ERDMA_ABI_VERSION       1 >>>>> ERDMA_ABI_VERSION should be 2？ >>>> Why? >>>> >>>> This field is for rdma-core and we don't have erdma provider in that >>>> library yet. It always starts from 1 for new drivers. >>> Please check this link: >>> http://mail.spinics.net/lists/linux-rdma/msg63012.html >>> >>> Jason mentioned in this link: >>> >>> " >>> /* >>>  * For 64 bit machines ABI version 1 and 2 are the same. Otherwise 32 >>>  * bit machines require ABI version 2 which guarentees the user and >>>  * kernel use the same ABI. >>>  */ >>> " >>> >>> Zhu Yanjun >> Even though I do not understand the reason, but as mentioned above, I think >> ERDMA_ABI_VERSION = 1 is fine, because ERDMA can only work in 64bit >> machines. > Jason's comment came after we discovered that many of our API structures had > problematic layout and weren't aligned to 64bits. This caused to issues when > the 32bits software tried to use 64bit kernel. Got it. Thanks Zhu Yanjun > > So we didn't have many choices but bump ABI versions for broken drivers > and RXE was one of them. > > You are proposing new driver, it should start from 1. > > Thanks