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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A300AC7619A for ; Wed, 12 Apr 2023 10:20:12 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pmXZx-00048Z-0e; Wed, 12 Apr 2023 06:19:53 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pmXZv-00048Q-Ug for qemu-devel@nongnu.org; Wed, 12 Apr 2023 06:19:51 -0400 Received: from mail-wr1-x42c.google.com ([2a00:1450:4864:20::42c]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1pmXZu-00016t-47 for qemu-devel@nongnu.org; Wed, 12 Apr 2023 06:19:51 -0400 Received: by mail-wr1-x42c.google.com with SMTP id v6so10324278wrv.8 for ; Wed, 12 Apr 2023 03:19:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1681294788; x=1683886788; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=MdMRVQyikzgklP5HeD0JaNCKv9EjjKEECDuNidbOaWU=; b=re7J+kpKqbqwYAfuCeZpmnkotwcvaEXakWvLPAFhGGnFXqBrZHLDomK+MYIOe235UH jQ1p4T4v/jJl8dk/K8U3p6bRbzRjxahkWHoO2S/6N5u7/uo13qgWygGtashU/KVvW7Zp /SyJ814crqrKb5EXG5aUFQfzHrfvoc8YJVirtXKLHyrtzOMKXBoFHerk+N+VtqqjDb03 YgmmwkjtpXc7viFf3EwY9OHFe4miCb8LQPoxu83ml/YpLfzL7QyiqlbxxAwnrLW3ekJs V0WVPbWYQRiplY4bo0zropYwq7dGm9Rxu1yKj3//qpxmGnmmkcMa97IuJ/SkrinuUFZ2 3kUQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1681294789; x=1683886789; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=MdMRVQyikzgklP5HeD0JaNCKv9EjjKEECDuNidbOaWU=; b=LY1tTujWkBWRNBxT9V7APYDegZA2gN3e4IMSuMmlm/3jt5s90vB8UkmDb3YvQD4fvd e3a0Ulf2UMSMfyPVm6qWqFVHzY1CAE/XW/H8oqnXxEfSCAbNXE7ldmyYFV4Lygtempsj 1jbuuNZYCx9FzzhyPRPon/88+22XKRPUceNTVWldDP4VJefItS16O0t1dkxkmN4Qy6/z QNpQnC3Z2RvKw/wBQtZxilZd/so7kpr39X3yAGu5uS3aNfDlAVXNxdRkY9Y8YlcSER2e d2c/e6HXCEwFUbbfXfJfpRs5eIrhGzIRbpETvjAZUSiJNNZuEx9bTCuZMUNt+OlF+XJK JZzw== X-Gm-Message-State: AAQBX9fjf7bzOFeP9P79wWHCmdRcnQMLhZG/NB2OtbYkzYw092iZIDEj wLWzkesxdwdieJ7LnnKARGUX6w== X-Google-Smtp-Source: AKy350bJwjU3/4IklcsuztuVaecKuk/4DL29jdt4pKo9bk7qTIc4GaSqJjsT5Q5lWnftKnLNYbik9w== X-Received: by 2002:adf:ce05:0:b0:2e5:1da2:2a06 with SMTP id p5-20020adfce05000000b002e51da22a06mr4325364wrn.5.1681294788750; Wed, 12 Apr 2023 03:19:48 -0700 (PDT) Received: from [192.168.69.115] ([176.187.216.226]) by smtp.gmail.com with ESMTPSA id t5-20020a5d6905000000b002efb4f2d240sm12828060wru.87.2023.04.12.03.19.47 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 12 Apr 2023 03:19:48 -0700 (PDT) Message-ID: <3d4d8f73-d96c-6616-0dc7-d839c84162bc@linaro.org> Date: Wed, 12 Apr 2023 12:19:46 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:102.0) Gecko/20100101 Thunderbird/102.9.1 Subject: Re: xen bits broke x32 build Content-Language: en-US To: Michael Tokarev , Peter Maydell Cc: Joao Martins , QEMU Developers , David Woodhouse References: <7739b40d-d8ba-ccde-cc6c-5d9f2c93a663@msgid.tls.msk.ru> <095a184b-a289-8807-efe8-882155b729c4@msgid.tls.msk.ru> From: =?UTF-8?Q?Philippe_Mathieu-Daud=c3=a9?= In-Reply-To: <095a184b-a289-8807-efe8-882155b729c4@msgid.tls.msk.ru> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=2a00:1450:4864:20::42c; envelope-from=philmd@linaro.org; helo=mail-wr1-x42c.google.com X-Spam_score_int: -42 X-Spam_score: -4.3 X-Spam_bar: ---- X-Spam_report: (-4.3 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-2.17, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On 11/4/23 19:30, Michael Tokarev wrote: > 11.04.2023 15:09, Peter Maydell wrote: > .. >> Frankly I would prefer to just say "we don't support x32". >> It's a weird non-standard configuration that as far as I'm >> aware is very little used. Its stats in the debian >> popularity-contest graphs peaked at 18 users in 2017, and >> have mostly been fluctuating between 1 and 3 for the last >> couple of years: >> https://popcon.debian.org/stat/sub-x32.png > > x32 was a nice idea but it lacked some final steps for it > to fly. I used to use a FreeRTOS POSIX/ucontext port compiled in x32. This was useful to mimic FreeRTOS baremetal ARM32 memory footprint. I see having a x32 QEMU binary as a masochist experiment =) > In my opinion anyway.  Its compactness and speed > are fantastic, - qemu build is about 10..15% faster with > x32 gcc than it is with x86_64 gcc. > > At the time debian picked it up, it was not very usable > b/c too many things didn't work and needed care.  Today, > much more software actually works on x32. It is more, > today with debian multiarch setup, it is possible to install > some *parts* of the system to be x32 while the rest being > x86_64, either for parts which benefits from x32 the most, > or the other way around, main x32 and some parts x86_64. > But it *still* lacks some infrastructure in debian, so it > is possible to do with stable or testing distribution, - > right now it is possible with unstable only.  Maybe we > can change that for bookworm+. > > The thing is that now, it is much more complete than it > was in 2017, and it'd be really sad if it goes away. > > x32 reveals some interesting problems in the code such > as type misuse, it already helped to find and fix some > bugs in some software, - for example in samba, where > a pointer was misused to store a time_t (which would > break with past-2038 time_t). Why wasn't this caught by other 32-bit target? > qemu never said it supports x32, and no one demanded > such support from it. It's interesting to have it working > there still, I *think*, as long as it does not require > extra efforts. > > I'm fine to maintain the change required to keep it at > least buildable on x32 in debian - again as long as it > does not require huge efforts. > >> We're currently planning to deprecate-and-drop 32-bit x86 >> hosts, which are much more widely used than this. I see >> no reason why we should care about this oddball failed >> experiment of an ABI... > > Thanks, > > /mjt >