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=-10.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 71C99C433E1 for ; Sat, 25 Jul 2020 06:38:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4D5FB20719 for ; Sat, 25 Jul 2020 06:38:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="tJ5xsDoW" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726817AbgGYGiS (ORCPT ); Sat, 25 Jul 2020 02:38:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56712 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725941AbgGYGiR (ORCPT ); Sat, 25 Jul 2020 02:38:17 -0400 Received: from mail-io1-xd44.google.com (mail-io1-xd44.google.com [IPv6:2607:f8b0:4864:20::d44]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8AD99C0619D3; Fri, 24 Jul 2020 23:38:16 -0700 (PDT) Received: by mail-io1-xd44.google.com with SMTP id l1so11982507ioh.5; Fri, 24 Jul 2020 23:38:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=b67K2e0Y5dToW3EVzzyFy6c/ZgBGS96NL2NdfK6mZtw=; b=tJ5xsDoW4PUzFtNZqDhB0WPHq5/F4E2INMVfk9DvHhEv6TP39pIvVwiQ/iehqWQDfn Ts+NvkXuZKk6HjJstXe+UucLuY6kTgBmvf9++HaW69gDDs8jkEh1sF5vUfnaC0Eeajk2 xf+MWhAZegVuIQhcN3AklESUcL+ag8SjBHkM3FoTmWHX7mpgkAj7nVfcJkXjlFMNuNCx +LvQpzpR+Hov6G3dioIWJKqrRGLMR9boPQMD6YVmnIoJfbJ/5dDBSnTb+E0xhl8btnaR hHehO3fk+O6bDvBrvPsy1qzLhgzTmoU6e10gtZbisQwabHiV0u5YfK8OuF8gqtZRe4K6 4qTg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=b67K2e0Y5dToW3EVzzyFy6c/ZgBGS96NL2NdfK6mZtw=; b=NXGcUy6B2u3/2ZuY3qeV1C9wRd8jlcQT1FGRh7QKD4lUD2A4ly2xnl8vFqZwvlFNMk Tow+SFMw+at4qiCi4C0Pw8awJfFwZ0sJIVqrCkpj3twkbJfGcb2Ng97fuIIlB7Lz0BYT EPnOngh0zfXchbbwjlC52cYDPeW/SwFHP0fsxgiwxKJaUSjVUf20cEF8C8XhvqiPVF0A Llug3y7C+LX897UESJpduqPEIoxzLulV2/7E+bI/PYNS2IhKvze0gF7QhdzIBc55J3VQ QyL/h17Eht/iDVi3PeLpP5J/bQB0QIp7FrjnvdCCzBkIJygkjuvmVfKRJWo4q7BrFBcV GhWg== X-Gm-Message-State: AOAM531IKF2oT1intosNSlnQ6SxWl9JvXJhcWZ2u5wsCggVrFa2U8lVI PUZIiTJRZ8Zaar5Pgkx1CFainQtNC6ndDgjgv5PC9F7uvzTmtQ== X-Google-Smtp-Source: ABdhPJwn08RlGtecKEm1Lv7crJTWeP4hLGBovlA63tFvTHNSLtGgoGEjvCM36mQDChbzFbWdJ5AMtbvZmwowmzDrLzc= X-Received: by 2002:a05:6638:2411:: with SMTP id z17mr14466514jat.50.1595659095871; Fri, 24 Jul 2020 23:38:15 -0700 (PDT) MIME-Version: 1.0 References: <1594896024-16624-1-git-send-email-chenhc@lemote.com> In-Reply-To: <1594896024-16624-1-git-send-email-chenhc@lemote.com> From: Huacai Chen Date: Sat, 25 Jul 2020 14:37:52 +0800 Message-ID: Subject: Re: [PATCH V2] MIPS: CPU#0 is not hotpluggable To: Thomas Bogendoerfer Cc: "open list:MIPS" , Fuxin Zhang , Zhangjin Wu , Jiaxun Yang , stable Content-Type: text/plain; charset="UTF-8" Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org Hi, Thomas, What do you think about this patch? Other archs also do the same thing except those support hotplug CPU#0. grep hotpluggable arch -rwI arch/riscv/kernel/setup.c: cpu->hotpluggable = cpu_has_hotplug(i); arch/powerpc/kernel/sysfs.c: BUG_ON(!c->hotpluggable); arch/powerpc/kernel/sysfs.c: c->hotpluggable = 1; arch/powerpc/kernel/sysfs.c: if (cpu_online(cpu) || c->hotpluggable) { arch/arm/kernel/setup.c: cpuinfo->cpu.hotpluggable = platform_can_hotplug_cpu(cpu); arch/sh/kernel/topology.c: c->hotpluggable = 1; arch/ia64/kernel/topology.c: * CPEI target, then it is hotpluggable arch/ia64/kernel/topology.c: sysfs_cpus[num].cpu.hotpluggable = 1; arch/xtensa/kernel/setup.c: cpu->hotpluggable = !!i; arch/s390/kernel/smp.c: c->hotpluggable = 1; arch/mips/kernel/topology.c: c->hotpluggable = 1; arch/arm64/kernel/cpuinfo.c: * In case the boot CPU is hotpluggable, we record its initial state and arch/arm64/kernel/setup.c: cpu->hotpluggable = cpu_can_disable(i); arch/x86/kernel/topology.c: per_cpu(cpu_devices, num).cpu.hotpluggable = 1; On Thu, Jul 16, 2020 at 6:38 PM Huacai Chen wrote: > > Now CPU#0 is not hotpluggable on MIPS, so prevent to create /sys/devices > /system/cpu/cpu0/online which confuses some user-space tools. > > Cc: stable@vger.kernel.org > Signed-off-by: Huacai Chen > --- > arch/mips/kernel/topology.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/mips/kernel/topology.c b/arch/mips/kernel/topology.c > index cd3e1f8..08ad637 100644 > --- a/arch/mips/kernel/topology.c > +++ b/arch/mips/kernel/topology.c > @@ -20,7 +20,7 @@ static int __init topology_init(void) > for_each_present_cpu(i) { > struct cpu *c = &per_cpu(cpu_devices, i); > > - c->hotpluggable = 1; > + c->hotpluggable = !!i; > ret = register_cpu(c, i); > if (ret) > printk(KERN_WARNING "topology_init: register_cpu %d " > -- > 2.7.0 >