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=-19.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 E94B9C4338F for ; Tue, 3 Aug 2021 11:46:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D411361107 for ; Tue, 3 Aug 2021 11:46:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236219AbhHCLqP (ORCPT ); Tue, 3 Aug 2021 07:46:15 -0400 Received: from mail.kernel.org ([198.145.29.99]:35534 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236075AbhHCLoq (ORCPT ); Tue, 3 Aug 2021 07:44:46 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id B795D60ED6; Tue, 3 Aug 2021 11:44:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1627991075; bh=SryW2t5Ze+b9tM3zx8bHTZ7bmm+Zqps8jt+VAt59OcU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qXSj2A51ULbHemUfD91xNI5WmFGS2jUHU1wjB6UWUYclpvmk9ckUqBh0z7YlsTwih atEijZlRR9XvHAcYV+/t0teCB4fb3Ol9dWfrTl3vb5WLUMIg/Fp9m8iO7Kl8jf4aWo hyLDRcB/smYPPhboSILSWi5RjSVxYezN6hZ0xxza9CTDYRvxAHAmaziQDDlK+vVoPy 3qukJsXI1SDrNtN80Q3LvZpzNEpl6uBlGtNqCKvBgV5SIaLFMePwHPmYg4lUXgKXIV hUH9YtTDoVGvvploG/DYQCX1tlCbXFyi8AfzsnW8mAua5jiTcubryDLmP3DkUEoF3p aeTZNbVNYf7/A== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Prarit Bhargava , Richard Henderson , Ivan Kokshaysky , Matt Turner , Sasha Levin , linux-alpha@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 4/5] alpha: Send stop IPI to send to online CPUs Date: Tue, 3 Aug 2021 07:44:28 -0400 Message-Id: <20210803114429.2252944-4-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210803114429.2252944-1-sashal@kernel.org> References: <20210803114429.2252944-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore 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 d0dccae53ba9..8a89b9adb4fe 100644 --- a/arch/alpha/kernel/smp.c +++ b/arch/alpha/kernel/smp.c @@ -585,7 +585,7 @@ 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