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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 3D21DC4321D for ; Wed, 22 Aug 2018 16:17:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E2DEF214DA for ; Wed, 22 Aug 2018 16:17:54 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E2DEF214DA Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727128AbeHVTnY (ORCPT ); Wed, 22 Aug 2018 15:43:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:41512 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726770AbeHVTnY (ORCPT ); Wed, 22 Aug 2018 15:43:24 -0400 Received: from gandalf.local.home (cpe-66-24-56-78.stny.res.rr.com [66.24.56.78]) (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 D0A9321486; Wed, 22 Aug 2018 16:17:51 +0000 (UTC) Date: Wed, 22 Aug 2018 12:17:49 -0400 From: Steven Rostedt To: Mike Galbraith Cc: Thomas Gleixner , Sebastian Andrzej Siewior , Julia Cartwright , linux-rt-users , LKML Subject: Re: [BUG v4.14-rt] kernel BUG at /work/rt/stable-rt.git/kernel/sched/core.c:1639! Message-ID: <20180822121749.5c4632d7@gandalf.local.home> In-Reply-To: <1534660115.6187.4.camel@gmx.de> References: <20180817162340.6e8482fd@gandalf.local.home> <1534588142.2516.10.camel@gmx.de> <1534597992.15909.17.camel@gmx.de> <1534660115.6187.4.camel@gmx.de> X-Mailer: Claws Mail 3.16.0 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 19 Aug 2018 08:28:35 +0200 Mike Galbraith wrote: > On Sat, 2018-08-18 at 15:13 +0200, Mike Galbraith wrote: > > seems it has be something from the 4.17 cycle that went back to 4.14- > > stable after 4.1[56]-stable trees went extinct. > > See ("sched/core: Require cpu_active() in select_task_rq(), for user tasks") > > Fix it like so? > > sched: Allow pinned user tasks to be awakened to the CPU they pinned > > Since 7af443ee16976, select_fallback_rq() will BUG() if the CPU to > which a task has pinned itself and pinned becomes !cpu_active() > while it slept. Serving a 10 megaton eviction notice is neither > helpful nor required, the task will migrate when it can do so. This seems to fix the issue that I was seeing. Thanks! I'll add this to my repo as well. -- Steve > > Signed-off-by: Mike Galbraith > --- > kernel/sched/core.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > --- a/kernel/sched/core.c > +++ b/kernel/sched/core.c > @@ -980,7 +980,7 @@ static inline bool is_cpu_allowed(struct > if (!cpumask_test_cpu(cpu, p->cpus_ptr)) > return false; > > - if (is_per_cpu_kthread(p)) > + if (is_per_cpu_kthread(p) || __migrate_disabled(p)) > return cpu_online(cpu); > > return cpu_active(cpu);