From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752539AbaEBPb6 (ORCPT ); Fri, 2 May 2014 11:31:58 -0400 Received: from www.linutronix.de ([62.245.132.108]:42328 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751636AbaEBPb5 (ORCPT ); Fri, 2 May 2014 11:31:57 -0400 Date: Fri, 2 May 2014 17:31:53 +0200 From: Sebastian Andrzej Siewior To: Steven Rostedt Cc: linux-kernel@vger.kernel.org, linux-rt-users , Thomas Gleixner , Carsten Emde , John Kacur , Paul Gortmaker , Mike Galbraith , Nicholas Mc Guire , Clark Williams Subject: Re: [PATCH RT 1/3] rt: Move migrate_disable up in trylocks Message-ID: <20140502153153.GG9178@linutronix.de> References: <20140501004757.583708392@goodmis.org> <20140501005004.241785945@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20140501005004.241785945@goodmis.org> X-Key-Id: 97C4700B X-Key-Fingerprint: 09E2 D1F3 9A3A FF13 C3D3 961C 0688 1C1E 97C4 700B User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Steven Rostedt | 2014-04-30 20:47:58 [-0400]: >From: Steven Rostedt > >The changes to move the migrate_disable() down in the trylocks() >caused race conditions to appear in the cpu hotplug code. The >migrate disables must be done before any of the rtmutexes are >taken, otherwise a lock may be held that prevents hotplug from >moving forward. > >Link: http://lkml.kernel.org/r/20140429201308.63292691@gandalf.local.home Okay. I am taking a modified version (so it applies) of this into v3.14 tree. Mike also suggested to drop migrate_disable-pushd-down-in-atomic_dec_and_spin_lo.patch because we which is basicaly the some thing. And then we have migrate_disable-pushd-down-in-rt_spin_trylock_irqsav.patch which we could drop as well for the same reason. Sebastian