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=-19.5 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 567B7C432BE for ; Tue, 10 Aug 2021 17:51:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3B1106023D for ; Tue, 10 Aug 2021 17:51:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236188AbhHJRvg (ORCPT ); Tue, 10 Aug 2021 13:51:36 -0400 Received: from mail.kernel.org ([198.145.29.99]:32800 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235860AbhHJRsy (ORCPT ); Tue, 10 Aug 2021 13:48:54 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 5C66E611CC; Tue, 10 Aug 2021 17:41:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1628617294; bh=6pfrQY5QyDEqVrt2lMWcXkE5SO4dTw+z8f67Irfj2EA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ah2GcT+HMW3JRXeKK6PAqNSIoXzOA3ALF6s3HJSnQZiY8UCfxSQVmB9TlCaYJdEnT v5Hq4sZ+jxMb3papYXXy4NKtns18yuuNeyJVwWvkN4iltCDWspvZUMWZ3oupsGp/uP +K/OyVCK/c29ZXerVhQQLY2uXQdoiiyaJOxlME8o= 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 5.10 131/135] alpha: Send stop IPI to send to online CPUs Date: Tue, 10 Aug 2021 19:31:05 +0200 Message-Id: <20210810173000.258797199@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210810172955.660225700@linuxfoundation.org> References: <20210810172955.660225700@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 4b2575f936d4..cb64e4797d2a 100644 --- a/arch/alpha/kernel/smp.c +++ b/arch/alpha/kernel/smp.c @@ -582,7 +582,7 @@ 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