From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751457AbdILSJH (ORCPT ); Tue, 12 Sep 2017 14:09:07 -0400 Received: from terminus.zytor.com ([65.50.211.136]:48495 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751054AbdILSJE (ORCPT ); Tue, 12 Sep 2017 14:09:04 -0400 Date: Tue, 12 Sep 2017 11:05:33 -0700 From: tip-bot for Peter Zijlstra Message-ID: Cc: peterz@infradead.org, linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@kernel.org, torvalds@linux-foundation.org, tglx@linutronix.de Reply-To: peterz@infradead.org, linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@kernel.org, torvalds@linux-foundation.org, tglx@linutronix.de In-Reply-To: <20170907150614.094206976@infradead.org> References: <20170907150614.094206976@infradead.org> To: linux-tip-commits@vger.kernel.org Subject: [tip:sched/urgent] sched/core: WARN() when migrating to an offline CPU Git-Commit-ID: 4ff9083b8a9a80bdf4ebbbec22cda4cbfb60f7aa X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 4ff9083b8a9a80bdf4ebbbec22cda4cbfb60f7aa Gitweb: http://git.kernel.org/tip/4ff9083b8a9a80bdf4ebbbec22cda4cbfb60f7aa Author: Peter Zijlstra AuthorDate: Thu, 7 Sep 2017 17:03:52 +0200 Committer: Ingo Molnar CommitDate: Tue, 12 Sep 2017 17:41:04 +0200 sched/core: WARN() when migrating to an offline CPU Migrating tasks to offline CPUs is a pretty big fail, warn about it. Signed-off-by: Peter Zijlstra (Intel) Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/20170907150614.094206976@infradead.org Signed-off-by: Ingo Molnar --- kernel/sched/core.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 136a76d..18a6966 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -1173,6 +1173,10 @@ void set_task_cpu(struct task_struct *p, unsigned int new_cpu) WARN_ON_ONCE(debug_locks && !(lockdep_is_held(&p->pi_lock) || lockdep_is_held(&task_rq(p)->lock))); #endif + /* + * Clearly, migrating tasks to offline CPUs is a fairly daft thing. + */ + WARN_ON_ONCE(!cpu_online(new_cpu)); #endif trace_sched_migrate_task(p, new_cpu);