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 461D3C61DA4 for ; Tue, 14 Feb 2023 14:18:31 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pRw8G-00024l-Rj; Tue, 14 Feb 2023 09:18:08 -0500 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 1pRw8F-0001zg-L8 for qemu-devel@nongnu.org; Tue, 14 Feb 2023 09:18:07 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pRw8A-0005jq-I4 for qemu-devel@nongnu.org; Tue, 14 Feb 2023 09:18:05 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1676384281; h=from:from:reply-to: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=CLjYbTIAnp+2IHzEYiZ07shJepB2lbeqvwYVdEYIf/E=; b=HwtYEBmgi34RK7hzDrXdKflwr6otpTy+6JVkQgaihpH3gM4gQ9JSZYk/OVA5AuQaxq8xXR p4/E+Mf5I4wh0RaX0F6txS4JZ4vKM+AyAABZgpTmwHILxglPQzhCBQts+Ue+rDKNydPr+A U3jTHcAZaKb9ntQL8R85c9EW6H8Qk90= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-664-jBeZnW48PSCcmhNXJKAgyg-1; Tue, 14 Feb 2023 09:17:58 -0500 X-MC-Unique: jBeZnW48PSCcmhNXJKAgyg-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id A829E3C10EC1; Tue, 14 Feb 2023 14:17:57 +0000 (UTC) Received: from redhat.com (unknown [10.33.36.149]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 33864492B04; Tue, 14 Feb 2023 14:17:54 +0000 (UTC) Date: Tue, 14 Feb 2023 14:17:52 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Paolo Bonzini Cc: Markus Armbruster , Peter Maydell , John Snow , qemu-devel , Cleber Rosa , Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= , Thomas Huth , Beraldo Leal , Michael Roth , Wainer dos Santos Moschetta , Qemu-block , Hanna Reitz , Alex =?utf-8?Q?Benn=C3=A9e?= , Kevin Wolf Subject: Re: [PATCH v2 6/7] CI: Stop building docs on centos8 Message-ID: References: <20230210003147.1309376-1-jsnow@redhat.com> <20230210003147.1309376-7-jsnow@redhat.com> <87cz6cpue3.fsf@pond.sub.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/2.2.9 (2022-11-12) X-Scanned-By: MIMEDefang 3.1 on 10.11.54.9 Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable 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: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Tue, Feb 14, 2023 at 03:03:54PM +0100, Paolo Bonzini wrote: > On Tue, Feb 14, 2023 at 12:49 PM Daniel P. Berrangé wrote: > > [quote] > > The motivation for this series is that Python 3.6 was EOL at the end of > > 2021; upstream tools are beginning to drop support for it, including > > setuptools, pylint, mypy, etc. As time goes by, it becomes more > > difficult to support and test against the full range of Python versions > > that QEMU supports. The closer we get to Python 3.12, the harder it will > > be to cover that full spread of versions. > > [/quote] > > > > this is all about new/eol versions of software upstream, and I don't > > think that's a justification. QEMU explicitly aims to use distro provided > > versions and upstream EOL status is not relevant in that context. Even > > if using "pip" to install it is possible to limit yourself to upstream > > releases which still support 3.6. > > > > There is the separate issue of Meson dropping python 3.6 which motivates > > Paolo's series. Again though, we don't have to increase our minimum meson > > version, because meson is working today. It is our choice to to increase > > it to use latest available meson features. At some point we can decide > > what we have is good enough and we don't have to keep chasing the latest > > features. Maybe we're not there yet, but we should think about when that > > would be. > > In the case of Meson, the main advantage is moving _all_ of the > emulator configury out of the configure script. This requires > add_global_dependencies which was added in 0.63. So in that case it > is indeed mostly about shiny new features and it's not absolutely > necessary. > > In the case of Python the issue is not the interpreter per se, though > there are a couple new feature in Python 3.7 that are quite nice (for > example improved data classes[1] or context variables[2]). The main > problem as far as I understood (and have seen in my experience) is > linting tools. New versions fix bugs that caused false positives, but > also become more strict at the same time. The newer versions at the > same time are very quick at dropping support for old versions of > Python; while older versions sometimes throw deprecation warnings on > new versions of Python. This makes it very hard to support a single > version of, say, mypy that works on all versions from RHEL8 and SLE15 > to Fedora 38 and Ubuntu 23.04. > > [1] https://peps.python.org/pep-0557/ > [2] https://peps.python.org/pep-0567/ > > In fact this issue is the reason why RHEL9 does not package any of > these tools and does not run them as part of building RPMs even though > in principle it would be a good idea; it's too much of a pain to have > a single version that works across all the packages in the > distribution. > > Regarding your other suggestion: > > > * For non-native library/applications dependancies we aim > > to support only the most recent distro version. Users > > of older distros may need to dynamically fetch newer > > deps. > > I think this is a good idea, but one issue with "only supporting the > most recent distro version" is SUSE. While the most recent version of > SLE is about 5 years old, there is no next version in sight---SUSE > instead is working on their "Adaptable Linux Platform", but it's still > in the prototype stage[3]. So alternatively we could put a 4 or 5 year > cutoff after which you need to fetch newer deps. Considering the > delays between freeze and release of distros like RHEL or SLE, in > practice we would probably keep Python versions supported for 6-7 > years. Yeah, that kind of problem with very old SUSE would push towards simply excluding the LTS distros, or excluding them if they're older than N years, and expect users of such old distros to download newer python modules, etc. With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|