From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752010AbaKFKp0 (ORCPT ); Thu, 6 Nov 2014 05:45:26 -0500 Received: from bombadil.infradead.org ([198.137.202.9]:50149 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751054AbaKFKpW (ORCPT ); Thu, 6 Nov 2014 05:45:22 -0500 Date: Thu, 6 Nov 2014 11:45:13 +0100 From: Peter Zijlstra To: Yuyang Du Cc: tglx@linutronix.de, mingo@redhat.com, fengguang.wu@intel.com, LKML , lkp@01.org, Yuanhan Liu , pjt@google.com, bsegall@google.com, rafael.j.wysocki@intel.com Subject: Re: [LKP] [sched] kernel BUG at kernel/smpboot.c:134! Message-ID: <20141106104513.GS10501@worktop.programming.kicks-ass.net> References: <20141104042922.GM27038@yliu-dev.sh.intel.com> <20141105180758.GA19218@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20141105180758.GA19218@intel.com> User-Agent: Mutt/1.5.22.1 (2013-10-16) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Nov 06, 2014 at 02:07:58AM +0800, Yuyang Du wrote: > Hi Peter and Thomas, > > LKP found a bug, and it was bisected to my rewrite patch: > http://article.gmane.org/gmane.linux.kernel/1818393/ > > But I really don't have a clue about why the patch can introduce > such a bug, as the patch does not modify anything related. Or maybe > the bug could be indirectly triggerd, just don't know how. > > To confirm it is not a false positive, we are rebasing the patch to > 3.18-rc3 to try to reproduce it, it is now ongoing. > > In addition, I noticed this thread about the same symptom: > http://thread.gmane.org/gmane.linux.kernel/1819348. > > Thomas should already have a fix to this. Right? Not quite; see https://lkml.org/lkml/2014/6/26/554 Let me read that thread though, maybe I can make sense of it.