From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756209AbYGUUXq (ORCPT ); Mon, 21 Jul 2008 16:23:46 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753140AbYGUUXf (ORCPT ); Mon, 21 Jul 2008 16:23:35 -0400 Received: from wf-out-1314.google.com ([209.85.200.174]:63509 "EHLO wf-out-1314.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750875AbYGUUXe (ORCPT ); Mon, 21 Jul 2008 16:23:34 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version :content-type:content-transfer-encoding:content-disposition :references; b=niJOfFwv/qEfE+vm4P7ceUO/d3eKHlzNd4tyNboPQDRVDhdaHLXwIfcdCrtTf9DU49 q0NYqb3NTDn65Ve4fentioyDoEWi9a9nK0vYgWDbTHpN5kVElp56jYYxi5+MbZ4Fk8Ga 8g6+fz8li4fP1coRtp5txKNhemlPfYJ7eiZOc= Message-ID: <19f34abd0807211323o11f38bf6ja756d196da1d7a1f@mail.gmail.com> Date: Mon, 21 Jul 2008 22:23:34 +0200 From: "Vegard Nossum" To: "Christoph Lameter" Subject: Re: [bug, netconsole, SLUB] BUG skbuff_head_cache: Poison overwritten Cc: "Ingo Molnar" , "Evgeniy Polyakov" , "Pekka Enberg" , linux-kernel@vger.kernel.org, netdev@vger.kernel.org, "Rafael J. Wysocki" , davem@davemloft.net In-Reply-To: <4884B724.40401@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20080717214222.GA29449@elte.hu> <20080718091146.GQ6875@elte.hu> <20080721094110.GA16029@elte.hu> <84144f020807210252k68d5cf65i8c7ae3c11cecc046@mail.gmail.com> <20080721100627.GA5953@2ka.mipt.ru> <20080721105051.GA5830@elte.hu> <19f34abd0807210403n1bca348fn83773b55a08b7993@mail.gmail.com> <4884B724.40401@linux-foundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 21, 2008 at 6:19 PM, Christoph Lameter wrote: >> (There was recently an odd case of kzalloc() succeeding even though it >> was called before the slab caches were initialized -- and it only >> generated a warning about irqs-on happening too early. I just mean to >> say that it _can_ happen. On another machine, it crashed >> spectacularly. I guess you're not enabling the netconsole before slab >> allocator is up?) > > Kzalloc for objects > 4k will succeed even during early boot since we will > directly call into the page allocator. It wasn't just that; it got into __slab_alloc() and out again. See the backtrace at http://lkml.org/lkml/2008/7/19/23 It's scary, I know. It's a good thing we have irqtrace :-) Vegard -- "The animistic metaphor of the bug that maliciously sneaked in while the programmer was not looking is intellectually dishonest as it disguises that the error is the programmer's own creation." -- E. W. Dijkstra, EWD1036