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 7425AC61DA4 for ; Mon, 6 Mar 2023 08:50:32 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pZ6VQ-0006xB-9e; Mon, 06 Mar 2023 03:47:40 -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 1pZ6V0-0006uj-Fo for qemu-devel@nongnu.org; Mon, 06 Mar 2023 03:47:19 -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 1pZ6Uy-00067J-LD for qemu-devel@nongnu.org; Mon, 06 Mar 2023 03:47:14 -0500 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-480-BweyhluRMwuANh_BPVGZnA-1; Mon, 06 Mar 2023 03:47:06 -0500 X-MC-Unique: BweyhluRMwuANh_BPVGZnA-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 6AB3C1C05EB7; Mon, 6 Mar 2023 08:47:05 +0000 (UTC) Received: from thuth.com (unknown [10.39.193.101]) by smtp.corp.redhat.com (Postfix) with ESMTP id 21233440DE; Mon, 6 Mar 2023 08:47:02 +0000 (UTC) From: Thomas Huth To: qemu-devel@nongnu.org, Peter Maydell , Daniel Berrange , Paolo Bonzini Cc: Markus Armbruster , =?UTF-8?q?Alex=20Benn=C3=A9e?= , qemu-arm@nongnu.org, Maxim Levitsky , libvir-list@redhat.com, Richard Henderson , xen-devel@lists.xenproject.org, Reinoud Zandijk , Wilfred Mallawa , John Paul Adrian Glaubitz Subject: [PATCH v4 1/5] docs/about/deprecated: Deprecate 32-bit x86 hosts for system emulation Date: Mon, 6 Mar 2023 09:46:54 +0100 Message-Id: <20230306084658.29709-2-thuth@redhat.com> In-Reply-To: <20230306084658.29709-1-thuth@redhat.com> References: <20230306084658.29709-1-thuth@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.1 on 10.11.54.5 Received-SPF: pass client-ip=170.10.133.124; envelope-from=thuth@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, 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 Hardly anybody still uses 32-bit x86 hosts today, so we should start deprecating them to stop wasting our time and CI minutes here. For example, there are also still some unresolved problems with these: When emulating 64-bit binaries in user mode, TCG does not honor atomicity for 64-bit accesses, which is "perhaps worse than not working at all" (quoting Richard). Let's simply make it clear that people should use 64-bit x86 hosts nowadays and we do not intend to fix/maintain the old 32-bit stuff. Reviewed-by: Daniel P. Berrangé Reviewed-by: Wilfred Mallawa Signed-off-by: Thomas Huth --- docs/about/deprecated.rst | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/docs/about/deprecated.rst b/docs/about/deprecated.rst index 15084f7bea..1ca9dc33d6 100644 --- a/docs/about/deprecated.rst +++ b/docs/about/deprecated.rst @@ -196,6 +196,17 @@ CI coverage support may bitrot away before the deprecation process completes. The little endian variants of MIPS (both 32 and 64 bit) are still a supported host architecture. +System emulation on 32-bit x86 hosts (since 8.0) +'''''''''''''''''''''''''''''''''''''''''''''''' + +Support for 32-bit x86 host deployments is increasingly uncommon in mainstream +OS distributions given the widespread availability of 64-bit x86 hardware. +The QEMU project no longer considers 32-bit x86 support for system emulation to +be an effective use of its limited resources, and thus intends to discontinue +it. Since all recent x86 hardware from the past >10 years is capable of the +64-bit x86 extensions, a corresponding 64-bit OS should be used instead. + + QEMU API (QAPI) events ---------------------- -- 2.31.1