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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 C6633C433FF for ; Tue, 13 Aug 2019 10:30:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9370520840 for ; Tue, 13 Aug 2019 10:30:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565692233; bh=j/Ac+6XtZpJGmOQ+jpLRFmXJgL6w5BpAMhdf9AX7A10=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=bEE1AUBIXm25MJblTEjwObA1MJRSvdDOPHW8KHUmeRCQMklZFS8/RsSrHkbjyo0ho O1OOBaCVzDZalL2A6Ru1bu11CbL/tTNDSAZ48NM4Jw4dk4bYZj+L/I1vNH16m09Ibs an6PbJoiPMqu4xYRw92Kks9aBhODPJYd6mQL3nNA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728378AbfHMKac (ORCPT ); Tue, 13 Aug 2019 06:30:32 -0400 Received: from mail.kernel.org ([198.145.29.99]:33012 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727491AbfHMKac (ORCPT ); Tue, 13 Aug 2019 06:30:32 -0400 Received: from localhost (unknown [193.47.165.251]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id EB86220679; Tue, 13 Aug 2019 10:30:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565692231; bh=j/Ac+6XtZpJGmOQ+jpLRFmXJgL6w5BpAMhdf9AX7A10=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Ns8J+hHAL3sSDmpUdNVxonC514aqG8ehS5kH38p95NWso8JLsphvUe0oQKqMBY2AF Hj9CU0s7LXlIxpjUtjPAoAVM10wOA5pVZCHGEMR48KVq+dZ5oxLLS1Aevje1/bLA2S 7T8mU/orqcTPFp6NZQ2iMyBJ4J2NDUw/sLQkmWII= Date: Tue, 13 Aug 2019 13:30:28 +0300 From: Leon Romanovsky To: Doug Ledford Cc: Bernard Metzler , linux-rdma@vger.kernel.org, jgg@ziepe.ca Subject: Re: [PATCH v2] Make user mmapped CQ arming flags field 32-bit size to remove 64-bit architecture dependency of siw. Message-ID: <20190813103028.GH29138@mtr-leonro.mtl.com> References: <20190809151816.13018-1-bmt@zurich.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.12.1 (2019-06-15) Sender: linux-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Mon, Aug 12, 2019 at 11:17:00AM -0400, Doug Ledford wrote: > On Fri, 2019-08-09 at 17:18 +0200, Bernard Metzler wrote: > > This patch changes the driver/user shared (mmapped) CQ notification > > flags field from unsigned 64-bits size to unsigned 32-bits size. This > > enables building siw on 32-bit architectures. > > > > This patch changes the siw-abi. On previously supported 64-bits > > little-endian architectures, the old siw user library remains > > usable, since the used 2 lowest bits of the new 32-bits field reside > > at the same memory location as those of the old 64-bits field. > > On 64-bits big-endian systems, the changes would break compatibility. > > Given the very short time of availability of siw with the current ABI, > > we do not expect current usage of siw on 64-bit big-endian systems. > > > > An according patch to change the siw user library fitting the new ABI > > will be provided to rdma-core. > > I changed the commit message somewhat. The siw driver was just taken > into the upstream kernel this merge window, so there is no need to be > apologetic about abi breakage, there are *no* released kernels with a > prior abi. We are only guaranteeing abi compatibility for the official > siw as taken into the upstream kernel and into rdma-core, and those will > be kept in sync starting with their first official release, which has > not yet happened. Until this rc cycle is complete, we can fix up > anything that needs fixed up, so if there are any other abi issues you > think you would like to address, well, chop! chop! ;-) > > With that said, thanks, applied to for-rc. > Please send relevant change to rdma-core too. Thanks