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=-7.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS autolearn=no 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 125BCC433E0 for ; Tue, 12 Jan 2021 02:06:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D687322E02 for ; Tue, 12 Jan 2021 02:06:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727235AbhALCGv (ORCPT ); Mon, 11 Jan 2021 21:06:51 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46710 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726963AbhALCGv (ORCPT ); Mon, 11 Jan 2021 21:06:51 -0500 Received: from mail-io1-xd2e.google.com (mail-io1-xd2e.google.com [IPv6:2607:f8b0:4864:20::d2e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DB252C061575 for ; Mon, 11 Jan 2021 18:06:10 -0800 (PST) Received: by mail-io1-xd2e.google.com with SMTP id o6so782538iob.10 for ; Mon, 11 Jan 2021 18:06:10 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:reply-to:from:date:message-id:subject:to:cc; bh=SA+ZWySdSGRKOuQ9QFJ4S4pXmYgE52dFwJbIuiWKKOc=; b=kw/kceOh7/102c5+8+2q4LskqQrb7/YPIqw/ZT6t7gVmYQvqwYqcH24i1uWyPIVmhV a3ppwSMhUpYUNz3WZxNwvnRp9YfMVZudVX10YwMrGH3OKbjD3wI3MbkFlSbVXWhK0hI9 hnvZnljU9b6rm8oZ6P8fM88ErVlXbIGuEWnWNbg0pSkBHFY9wYNPvr4Q6uroAsvYEFIn HiquTwgVStHj0Fp2KZ6iAU0rbGF2acQqviOiNLOMVDdAXHqdKTGPfiecBwGrbJFXHHgb COO5FNGMJgThvhnibBNy3vgrh38xdsOiK8ikkMQ2jcfJbEIfAYYDhghx9/5vEe8gmmN5 FFMA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:reply-to:from:date:message-id :subject:to:cc; bh=SA+ZWySdSGRKOuQ9QFJ4S4pXmYgE52dFwJbIuiWKKOc=; b=msbdlv3YHkYucw58a6YnbQGkpIUVL4kGJEA8v0gyLjvN1Wur0Qr8G1ruBg9wwoOZlQ 8fARa19EKJksdJDQJLriGIA6bl0zqMG/pAfgfywr7U6bVm3OwubmEXrOQ+ccJcBCTGCX lDYMv58yD1Yd8gTpf4NmcBTF32NOXxqK9IZu9f0MMDb1COvGylDKzCaupJeXQmAW0fBR fLGO7IiNr1f8zge7uKGvoWBcaXL+3Ih1LyiBVH3lHijOAuUXI53Q/G4CFYp6lQIeFcr5 QXh6Kp8CzFBLWWBf/kop5jL4bA0aSj9SMI/121Mr5dITjqPkAsRnNadJtL4qkQ0QSnMo ODaA== X-Gm-Message-State: AOAM532aLg6KPWgueDe46vnHraprCqPSObhahR2jjvwRID8qzJRwyEEI h3f7qqZK1BVpB3I3bzLx6zH6+0reord+uf9EkcSDxbMYk66c X-Google-Smtp-Source: ABdhPJwRZAISa2oPkM0NmB6upeFC46GWWA8ZNT8lnFvUr3n8W4QM4Z3bsW7a9zos3y0/nrblDyDQtd4sWnSXCroYqSY= X-Received: by 2002:a92:4101:: with SMTP id o1mr1877398ila.82.1610417170016; Mon, 11 Jan 2021 18:06:10 -0800 (PST) MIME-Version: 1.0 Reply-To: whiteheadm@acm.org From: tedheadster Date: Mon, 11 Jan 2021 21:05:59 -0500 Message-ID: Subject: Re: Old platforms: bring out your dead To: Linux Kernel Mailing List Cc: Shuah Khan , Krzysztof Adamski , Oleksij Rempel , Baruch Siach , Russell King - ARM Linux , Daniel Tang , =?UTF-8?Q?Uwe_Kleine=2DK=C3=B6nig?= , Jamie Iles , Barry Song , Viresh Kumar , Linus Walleij , Jonas Jensen , Marc Gonzalez , Hartley Sweeten , Lubomir Rintel , Neil Armstrong , Shawn Guo , Alex Elder , Alexander Shiyan , Koen Vandeputte , Hans Ulli Kroll , Vladimir Zapolskiy , Wei Xu , Steven Rostedt , Yoshinori Sato , Mark Salter , Michael Ellerman , Geert Uytterhoeven , Thomas Bogendoerfer Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Arnd, > * 80486SX/DX: 80386 CPUs were dropped in 2012, and there are > indications that 486 have no users either on recent kernels. > There is still the Vortex86 family of SoCs, and the oldest of those were > 486SX-class, but all the modern ones are 586-class. I actively use the i486DX systems for regression testing and they have proven useful for detecting bugs in both the kernel and GCC (see below). I am also about to use them as testing systems for kernel programming students. I would hate to lose this platform as a student learning opportunity. Here are just some of the patches that I have worked on myself: Kernel patches i486 testing uncovered: x86/boot: Fix another __read_cr4() case on 486 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=192d1dccbfc5b901b66527df9df80304693cf06e x86/CPU: Change query logic so CPUID is enabled before testing https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?id=2893cc8ff892fa74972d8dc0e1d0dc65116daaa3 GCC patches i486 contributed to: ibgcc calls __get_cpuid with 0 level breaks on early 486 https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=a6c78ea30381cc28ea0b2cf8f0bd584a91dda948 ICE in gen_lowpart_general, at rtlhooks.c:63 https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=980c8afc0961da4b4567a5abe85b6048d501a1ad So, these systems are _quietly_ being used, and helping to contribute, it's just not glamorous, eye-catching work. - Matthew Whitehead