From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qg0-f42.google.com (mail-qg0-f42.google.com [209.85.192.42]) by kanga.kvack.org (Postfix) with ESMTP id 7B48A6B0031 for ; Mon, 10 Mar 2014 21:25:07 -0400 (EDT) Received: by mail-qg0-f42.google.com with SMTP id q107so9680663qgd.1 for ; Mon, 10 Mar 2014 18:25:07 -0700 (PDT) Received: from mx1.redhat.com (mx1.redhat.com. [209.132.183.28]) by mx.google.com with ESMTP id b7si10406202qad.174.2014.03.10.18.25.06 for ; Mon, 10 Mar 2014 18:25:07 -0700 (PDT) Date: Mon, 10 Mar 2014 21:24:55 -0400 From: Dave Jones Subject: Re: oops in slab/leaks_show Message-ID: <20140311012455.GA5151@redhat.com> References: <20140307025703.GA30770@redhat.com> <20140311003459.GA25657@lge.com> <20140311010135.GA25845@lge.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140311010135.GA25845@lge.com> Sender: owner-linux-mm@kvack.org List-ID: To: Joonsoo Kim Cc: Christoph Lameter , Linux Kernel , Pekka Enberg , linux-mm@kvack.org, David Rientjes , Al Viro On Tue, Mar 11, 2014 at 10:01:35AM +0900, Joonsoo Kim wrote: > On Tue, Mar 11, 2014 at 09:35:00AM +0900, Joonsoo Kim wrote: > > On Fri, Mar 07, 2014 at 11:18:30AM -0600, Christoph Lameter wrote: > > > Joonsoo recently changed the handling of the freelist in SLAB. CCing him. > > > > > > > I pretty much always use SLUB for my fuzzing boxes, but thought I'd give SLAB a try > > > > for a change.. It blew up when something tried to read /proc/slab_allocators > > > > (Just cat it, and you should see the oops below) > > > > Hello, Dave. > > > > Today, I did a test on v3.13 which contains all my changes on the handling of > > the freelist in SLAB and couldn't trigger oops by just 'cat /proc/slab_allocators'. > > > > So I look at the code and find that there is race window if there is multiple users > > doing 'cat /proc/slab_allocators'. Did your test do that? > > Opps, sorry. I am misunderstanding something. Maybe there is no race. > Anyway, How do you test it? 1. build kernel with CONFIG_SLAB=y. 2. boot kernel 3. cat /proc/slab_allocators that's it. Dave -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org