Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756064AbaAWBxE (ORCPT ); Wed, 22 Jan 2014 20:53:04 -0500 Received: from mx1.redhat.com ([209.132.183.28]:44124 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752950AbaAWBxB (ORCPT ); Wed, 22 Jan 2014 20:53:01 -0500 Date: Wed, 22 Jan 2014 20:52:41 -0500 From: Dave Jones To: David Rientjes Cc: Sasha Levin , khlebnikov@openvz.org, Andrew Morton , "linux-mm@kvack.org" , LKML Subject: Re: mm: BUG: Bad rss-counter state Message-ID: <20140123015241.GA947@redhat.com> Mail-Followup-To: Dave Jones , David Rientjes , Sasha Levin , khlebnikov@openvz.org, Andrew Morton , "linux-mm@kvack.org" , LKML References: <52E06B6F.90808@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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 On Wed, Jan 22, 2014 at 05:39:25PM -0800, David Rientjes wrote: > > While fuzzing with trinity running inside a KVM tools guest using latest -next > > kernel, > > I've stumbled on a "mm: BUG: Bad rss-counter state" error which was pretty > > non-obvious > > in the mix of the kernel spew (why?). > > > > It's not a fatal condition and there's only a few possible stack traces > that could be emitted during the exit() path. I don't see how we could > make it more visible other than its log-level which is already KERN_ALERT. > > > I've added a small BUG() after the printk() in check_mm(), and here's the full > > output: > > > > Worst place to add it :) At line 562 of kernel/fork.c in linux-next > you're going to hit BUG() when there may be other counters that are also > bad and they don't get printed. > > > [ 318.334905] BUG: Bad rss-counter state mm:ffff8801e6dec000 idx:0 val:1 > > So our mm has a non-zero MM_FILEPAGES count, but there's nothing that was > cited that would tell us what that is so there's not much to go on, unless > someone already recognizes this as another issue. Is this reproducible on > 3.13 or only on linux-next? Sasha, is this the current git tree version of Trinity ? (I'm wondering if yesterdays munmap changes might be tickling this bug). Dave -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/