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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT 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 AC8D8C4320A for ; Fri, 13 Aug 2021 15:08:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9161E61102 for ; Fri, 13 Aug 2021 15:08:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241258AbhHMPJB (ORCPT ); Fri, 13 Aug 2021 11:09:01 -0400 Received: from mail.kernel.org ([198.145.29.99]:51318 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241206AbhHMPIx (ORCPT ); Fri, 13 Aug 2021 11:08:53 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id E0DF86109E; Fri, 13 Aug 2021 15:08:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1628867306; bh=WTcoYn764YW43k/A0/6SVzKX1dcFrJatAQAOKKY6Mcw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Cv9Ftijk+fNhsdmCZkc9Fwi0eW509mbllaGuRLUmzbJ3sdj0A3nqknDtRjw/+kmkE G9dt/j72DMsdS1wUgszkU2g9lyD6MUyo4BEgwvh1OTP9fnxVDB9OKXN68KOgVk9Al2 SrB+oobTFbAPbJCa2iUCOlV34hF0lgYsgbr8SAy4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Prarit Bhargava , Richard Henderson , Ivan Kokshaysky , Matt Turner , Sasha Levin Subject: [PATCH 4.4 20/25] alpha: Send stop IPI to send to online CPUs Date: Fri, 13 Aug 2021 17:06:44 +0200 Message-Id: <20210813150521.373297353@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210813150520.718161915@linuxfoundation.org> References: <20210813150520.718161915@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Prarit Bhargava [ Upstream commit caace6ca4e06f09413fb8f8a63319594cfb7d47d ] This issue was noticed while debugging a shutdown issue where some secondary CPUs are not being shutdown correctly. A fix for that [1] requires that secondary cpus be offlined using the cpu_online_mask so that the stop operation is a no-op if CPU HOTPLUG is disabled. I, like the author in [1] looked at the architectures and found that alpha is one of two architectures that executes smp_send_stop() on all possible CPUs. On alpha, smp_send_stop() sends an IPI to all possible CPUs but only needs to send them to online CPUs. Send the stop IPI to only the online CPUs. [1] https://lkml.org/lkml/2020/1/10/250 Signed-off-by: Prarit Bhargava Cc: Richard Henderson Cc: Ivan Kokshaysky Signed-off-by: Matt Turner Signed-off-by: Sasha Levin --- arch/alpha/kernel/smp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/alpha/kernel/smp.c b/arch/alpha/kernel/smp.c index 2f24447fef92..1543b571bd99 100644 --- a/arch/alpha/kernel/smp.c +++ b/arch/alpha/kernel/smp.c @@ -584,7 +584,7 @@ void smp_send_stop(void) { cpumask_t to_whom; - cpumask_copy(&to_whom, cpu_possible_mask); + cpumask_copy(&to_whom, cpu_online_mask); cpumask_clear_cpu(smp_processor_id(), &to_whom); #ifdef DEBUG_IPI_MSG if (hard_smp_processor_id() != boot_cpu_id) -- 2.30.2