Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933470AbaD2KAF (ORCPT ); Tue, 29 Apr 2014 06:00:05 -0400 Received: from e23smtp05.au.ibm.com ([202.81.31.147]:45804 "EHLO e23smtp05.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751942AbaD2KAC (ORCPT ); Tue, 29 Apr 2014 06:00:02 -0400 Message-ID: <535F77E8.2040000@linux.vnet.ibm.com> Date: Tue, 29 Apr 2014 15:29:04 +0530 From: "Srivatsa S. Bhat" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:15.0) Gecko/20120828 Thunderbird/15.0 MIME-Version: 1.0 To: Linus Torvalds CC: Davidlohr Bueso , Hugh Dickins , Linux MM , "linux-kernel@vger.kernel.org" , Rik van Riel , Michel Lespinasse , "akpm@linux-foundation.org" Subject: Re: [BUG] kernel BUG at mm/vmacache.c:85! References: <535EA976.1080402@linux.vnet.ibm.com> <1398723290.25549.20.camel@buesod1.americas.hpqcorp.net> In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 14042909-1396-0000-0000-000004C19D1B Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/29/2014 03:55 AM, Linus Torvalds wrote: > On Mon, Apr 28, 2014 at 3:14 PM, Davidlohr Bueso wrote: >> >> I think that returning some stale/bogus vma is causing those segfaults >> in udev. It shouldn't occur in a normal scenario. What puzzles me is >> that it's not always reproducible. This makes me wonder what else is >> going on... > > I've replaced the BUG_ON() with a WARN_ON_ONCE(), and made it be > unconditional (so you don't have to trigger the range check). > > That might make it show up earlier and easier (and hopefully closer to > the place that causes it). Maybe that makes it easier for Srivatsa to > reproduce this. It doesn't make *my* machine do anything different, > though. > > Srivatsa? It's in current -git. > I tried this, but still nothing so far. I rebooted 10-20 times, and also tried multiple runs of multi-threaded ebizzy and kernel compilations, but none of this hit the warning. Is there anything more specific I can run to increase the chances of hitting this? I guess a test-case might be too much to ask since I'm the first one hitting this, but if anybody has suggestions of scenarios which have a higher likelihood of hitting this (like running multi- threaded workloads or whatever), I could probably give it a try as well. Thank you! Regards, Srivatsa S. Bhat -- 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/