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.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 smtp.lore.kernel.org (Postfix) with ESMTPS id 25985C369CB for ; Sat, 26 Apr 2025 19:10:15 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.969372.1358497 (Exim 4.92) (envelope-from ) id 1u8kuX-0006bE-Gj; Sat, 26 Apr 2025 19:10:01 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 969372.1358497; Sat, 26 Apr 2025 19:10:01 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1u8kuX-0006b7-Dl; Sat, 26 Apr 2025 19:10:01 +0000 Received: by outflank-mailman (input) for mailman id 969372; Sat, 26 Apr 2025 19:09:59 +0000 Received: from se1-gles-sth1-in.inumbo.com ([159.253.27.254] helo=se1-gles-sth1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1u8kuV-0006b1-8U for xen-devel@lists.xenproject.org; Sat, 26 Apr 2025 19:09:59 +0000 Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by se1-gles-sth1.inumbo.com (Halon) with ESMTPS id 0b2568ef-22d2-11f0-9eb3-5ba50f476ded; Sat, 26 Apr 2025 21:09:58 +0200 (CEST) Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id 98CDB6115D; Sat, 26 Apr 2025 19:09:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 92973C4CEE2; Sat, 26 Apr 2025 19:09:52 +0000 (UTC) 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" X-Inumbo-ID: 0b2568ef-22d2-11f0-9eb3-5ba50f476ded DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1745694596; bh=07l3WctL9NqhfdN89XZmqkm5zTdk90Q/ztrcy/DErjg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=NVfY67VWhCVqlpe7m2m9BJZW2pOZWxvq9m7gF6cpOJC+vZijOXds7YNWbZ8+8wBvK v0gjXTJEl6up/BuqExzotOfQNrcXc/iSM12njyAUxBde+8Eggt3fT+zKp8fTm6tuJg PqZcKEa/R/OEzNXAO+yXnU6NhDVPIpDthVGKhEvfVRk+4pGzH/5SzmMqyuTgw06Net 2QKbaK8Jk0J2yQtumpT3m2LmZs6und/oVXYc2A3uUnU4wd5IXdmNpOFcvbYSDKcFti t0C5fSSHVbnxYk09jk/DjG8CzVR9FPjIaAhbJGXXFKVxVxysfDBpTOKlMWy2bDoXHd +ZfFc3/gEW3qQ== Date: Sat, 26 Apr 2025 21:09:50 +0200 From: Ingo Molnar To: Arnd Bergmann Cc: Arnd Bergmann , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Juergen Gross , Boris Ostrovsky , Alexander Usyskin , Greg Kroah-Hartman , Mateusz =?utf-8?Q?Jo=C5=84czyk?= , Mike Rapoport , Ard Biesheuvel , Peter Zijlstra , linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org, Linus Torvalds Subject: Re: [PATCH] [RFC] x86/cpu: rework instruction set selection Message-ID: References: <20250425141740.734030-1-arnd@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: * Arnd Bergmann wrote: > CMOV is missing not just on old Socket 5/7 CPUs (Pentium MMX, AMD K6, > Cyrix MII) but also newer embedded Via C3, Geode GX and > Vortex86DX/MX/EX/DX2. The replacement Nehemiah (2003), GeodeLX (2005) > and Vortex86DX3/EX2 (2015!) have CMOV, but the old ones were sold > alongside them for years, and some of the 586-class Vortex86 products > are still commercially available. Very few (if any) of the commercially available products will run modern 6.16+ kernels, right? Note that the real danger the 32-bit x86 kernel is going to be facing in 2-5 years is total removal due to lack of development interest, but I think we can support 686+ reasonably far into the future, and can keep it tested reasonably - while covering like 99%+ of the currently available 32-bit-only x86 products on the market. The fewer variants, the better. Thanks, Ingo