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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 6082FC43381 for ; Mon, 1 Apr 2019 17:58:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2DAAD2084B for ; Mon, 1 Apr 2019 17:58:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554141515; bh=Ke8jW1ZlHA9oZ0Ee6iTxgd+6xftHt32sI5lq0CU2q/A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=S11PSrKJEbRCBM/Dfpf/U+64t8O4wM3/vAqJGzEFpMUR2Hn8cUdHxHc0+w0yqPK8Q ZVYDKgp+9vA4hxSjs2SM09yqys9Ng5a4Fgjw0EXbksp/k8baNDo6SZMMsSJ7DQsan5 gYeZwX4zYBQZaZWMR7UhlghAbHp8dJBt/zJO2g5s= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730994AbfDARSm (ORCPT ); Mon, 1 Apr 2019 13:18:42 -0400 Received: from mail.kernel.org ([198.145.29.99]:46134 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728594AbfDARSk (ORCPT ); Mon, 1 Apr 2019 13:18:40 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 8F33E218FF; Mon, 1 Apr 2019 17:18:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554139120; bh=Ke8jW1ZlHA9oZ0Ee6iTxgd+6xftHt32sI5lq0CU2q/A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=heWD6KHsXixO4YdyJRVd/gvPR4zyQ18iB1xzNVSfgIM5swTafDIalo87rvuW6hotK SEHvIuVAYryAG7KBVD2QCwe6XdjCvPpdEUI+ooj/xppKjLcO0G7uQvn7Q4hpQUZ4F9 +abWwvJXAc5X6aQ/qf85KOVL6778fBLWSMCF0EeE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Maxime Coquelin , Thomas Gleixner , Peter Zijlstra , Oleg Nesterov , Michael Ellerman , Nicholas Piggin , Don Zickus , Ricardo Neri Subject: [PATCH 4.19 120/134] watchdog: Respect watchdog cpumask on CPU hotplug Date: Mon, 1 Apr 2019 19:02:36 +0200 Message-Id: <20190401170055.561424856@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190401170044.243719205@linuxfoundation.org> References: <20190401170044.243719205@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Thomas Gleixner commit 7dd47617114921fdd8c095509e5e7b4373cc44a1 upstream. The rework of the watchdog core to use cpu_stop_work broke the watchdog cpumask on CPU hotplug. The watchdog_enable/disable() functions are now called unconditionally from the hotplug callback, i.e. even on CPUs which are not in the watchdog cpumask. As a consequence the watchdog can become unstoppable. Only invoke them when the plugged CPU is in the watchdog cpumask. Fixes: 9cf57731b63e ("watchdog/softlockup: Replace "watchdog/%u" threads with cpu_stop_work") Reported-by: Maxime Coquelin Signed-off-by: Thomas Gleixner Tested-by: Maxime Coquelin Cc: Peter Zijlstra Cc: Oleg Nesterov Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Don Zickus Cc: Ricardo Neri Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1903262245490.1789@nanos.tec.linutronix.de Signed-off-by: Greg Kroah-Hartman --- kernel/watchdog.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -547,13 +547,15 @@ static void softlockup_start_all(void) int lockup_detector_online_cpu(unsigned int cpu) { - watchdog_enable(cpu); + if (cpumask_test_cpu(cpu, &watchdog_allowed_mask)) + watchdog_enable(cpu); return 0; } int lockup_detector_offline_cpu(unsigned int cpu) { - watchdog_disable(cpu); + if (cpumask_test_cpu(cpu, &watchdog_allowed_mask)) + watchdog_disable(cpu); return 0; }