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=-12.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 743D3C07E95 for ; Tue, 13 Jul 2021 13:01:01 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 3E85E60240 for ; Tue, 13 Jul 2021 13:01:01 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3E85E60240 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=xen.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.155360.286788 (Exim 4.92) (envelope-from ) id 1m3I1l-0007i6-7z; Tue, 13 Jul 2021 13:00:45 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 155360.286788; Tue, 13 Jul 2021 13:00:45 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1m3I1l-0007hz-51; Tue, 13 Jul 2021 13:00:45 +0000 Received: by outflank-mailman (input) for mailman id 155360; Tue, 13 Jul 2021 13:00:43 +0000 Received: from mail.xenproject.org ([104.130.215.37]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1m3I1j-0007ht-Dn for xen-devel@lists.xenproject.org; Tue, 13 Jul 2021 13:00:43 +0000 Received: from xenbits.xenproject.org ([104.239.192.120]) by mail.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1m3I1g-0005Z3-DC; Tue, 13 Jul 2021 13:00:40 +0000 Received: from [54.239.6.178] (helo=a483e7b01a66.ant.amazon.com) by xenbits.xenproject.org with esmtpsa (TLS1.3:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.92) (envelope-from ) id 1m3I1g-0007rx-6K; Tue, 13 Jul 2021 13:00:40 +0000 X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=xen.org; s=20200302mail; h=Content-Transfer-Encoding:Content-Type:In-Reply-To: MIME-Version:Date:Message-ID:From:References:Cc:To:Subject; bh=kUHn0hW3j0aohKyPohiOuURVNltDR9boIkEquO8Icfc=; b=hjNdpOjcLuyB/ma5yv2PCVT13s ICBhFkcdiGmCHu8PgtJbKjdaJcsamSoxUVOKljGaHTxgbfRgQV3mqfPMimi0pyTprpmgUUnhVriYJ 7LxCjq52FmEkVgxSqGUyMCQCSZVwmERrfi4gcmT803RHNhNJxbCKLT4AeHARTY5u1NRA=; Subject: Re: [PATCH] stubdom: foreignmemory: Fix build after 0dbb4be739c5 To: Andrew Cooper , Juergen Gross , xen-devel@lists.xenproject.org Cc: Julien Grall , Ian Jackson , Wei Liu , Costin Lupu References: <20210713092019.7379-1-julien@xen.org> <0698e4b1-8fb9-919e-e9a2-1b135a808e3e@suse.com> <756ba923-17a6-0889-cc7e-bcd43a5eb258@citrix.com> <3505f2da-4c41-f5ca-d775-814d038d5bad@xen.org> From: Julien Grall Message-ID: <3c819563-b354-5527-050d-f698324d6021@xen.org> Date: Tue, 13 Jul 2021 14:00:38 +0100 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 8bit On 13/07/2021 13:39, Andrew Cooper wrote: > On 13/07/2021 12:53, Julien Grall wrote: >> Hi Andrew, >> >> On 13/07/2021 12:23, Andrew Cooper wrote: >>> On 13/07/2021 12:21, Julien Grall wrote: >>>> Hi Andrew, >>>> >>>> On 13/07/2021 10:35, Andrew Cooper wrote: >>>>> On 13/07/2021 10:27, Juergen Gross wrote: >>>>>> On 13.07.21 11:20, Julien Grall wrote: >>>>>>> From: Julien Grall >>>>>>> >>>>>>> Commit 0dbb4be739c5 add the inclusion of xenctrl.h from private.h >>>>>>> and >>>>>>> wreck the build in an interesting way: >>>>>>> >>>>>>> In file included from xen/stubdom/include/xen/domctl.h:39:0, >>>>>>>                     from xen/tools/include/xenctrl.h:36, >>>>>>>                     from private.h:4, >>>>>>>                     from minios.c:29: >>>>>>> xen/include/public/memory.h:407:5: error: expected >>>>>>> specifier-qualifier-list before ‘XEN_GUEST_HANDLE_64’ >>>>>>>         XEN_GUEST_HANDLE_64(const_uint8) buffer; >>>>>>>         ^~~~~~~~~~~~~~~~~~~ >>>>>>> >>>>>>> This is happening because xenctrl.h defines __XEN_TOOLS__ and >>>>>>> therefore >>>>>>> the public headers will start to expose the non-stable ABI. However, >>>>>>> xen.h has already been included by a mini-OS header before hand. So >>>>>>> there is a mismatch in the way the headers are included. >>>>>>> >>>>>>> For now solve it in a very simple (and gross) way by including >>>>>>> xenctrl.h before the mini-os headers. >>>>>>> >>>>>>> Fixes: 0dbb4be739c5 ("tools/libs/foreignmemory: Fix PAGE_SIZE >>>>>>> redefinition error") >>>>>>> Signed-off-by: Julien Grall >>>>>>> >>>>>>> --- >>>>>>> >>>>>>> Cc: Andrew Cooper >>>>>>> >>>>>>> I couldn't find a better way with would not result to revert the >>>>>>> patch >>>>>>> (and break build on some system) or involve a longer rework of the >>>>>>> headers. >>>>>> >>>>>> Just adding a "#define __XEN_TOOLS__" before the #include statements >>>>>> doesn't work? >>>>> >>>>> Not really, no. >>>>> >>>>> libxenforeignmem has nothing at all to do with any Xen unstable >>>>> interfaces.  Including xenctrl.h in the first place was wrong, because >>>>> it is an unstable library.  By extension, the use of XC_PAGE_SIZE is >>>>> also wrong. >>>> >>>> Well... Previously we were using PAGE_SIZE which is just plain wrong >>>> on Arm. >>>> >>>> At the moment, we don't have a way to query the page granularity of >>>> the hypervisor. But we know it can't change because of the way the >>>> current ABI was designed. Hence why using XC_PAGE_SIZE is the best of >>>> option we had until we go to ABIv2. >>> >>> Still doesn't mean that XC_PAGE_SIZE was ok to use. >> >> Note that I wrote "best of the option". The series has been sitting >> for ages with no-one answering... You could have provided your option >> back then if you thought it wasn't a good use... > > On a series I wasn't even CC'd on? You had the link on IRC because we discussed it. > > And noone had even bothered to compile test? Well, that was a mistake. At the same time, if it compiled the "issue" you describe would have gone unnoticed. ;) >> >>> >>> Sounds like the constant needs moving into the Xen public headers, and >>> the inclusions of xenctrl.h into stable libraries needs reverting. >> >> This could work. Are you planning to work on it? > > No.  I don't have enough time to do my own work thanks to all the CI > breakage and regressions being committed. > This needs fixing, or the original series reverting for 4.16 because the > current form (with or without this emergency build fix) isn't acceptable > to release with. I disagree with this caracterization. Yes, this is including a non-stable header but it doesn't link with non-stable library. In fact, reverting the series will bring back two issues: 1) Xen tools will not build on all the distros 2) Using PAGE_{SIZE, SHIFT} break arm tools because the userspace is not meant to rely on a given kernel page granularity. So this doesn't look like a priority for 4.16. Although, it would be a nice clean-up to have so the libraries are more compliant. Cheers, -- Julien Grall