From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933600AbYEBBXe (ORCPT ); Thu, 1 May 2008 21:23:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757466AbYEBBXY (ORCPT ); Thu, 1 May 2008 21:23:24 -0400 Received: from mx2.suse.de ([195.135.220.15]:55241 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757182AbYEBBXX (ORCPT ); Thu, 1 May 2008 21:23:23 -0400 Date: Fri, 2 May 2008 03:23:22 +0200 From: Nick Piggin To: Christoph Lameter Cc: "Ahmed S. Darwish" , Linux Memory Management List , Linux Kernel Mailing List Subject: Re: [patch] SLQB v2 Message-ID: <20080502012321.GE30768@wotan.suse.de> References: <20080410193137.GB9482@wotan.suse.de> <20080415034407.GA9120@ubuntu> <20080501015418.GC15179@wotan.suse.de> <20080502004325.GA30768@wotan.suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.9i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 01, 2008 at 06:14:52PM -0700, Christoph Lameter wrote: > On Fri, 2 May 2008, Nick Piggin wrote: > > > If you are not debugging sl?b.c code/pages, then why would you want to see > > what those fields are? > > Because you are f.e. inspecting a core dump and want to see why certain > fields have certain values to verify that the structures were not > overwrittten or corrupted etc. But overloading struct page values happens in other places too. Putting everything into struct page is not scalable. We could also make kmalloc return not a void pointer put a pointer to a union of every possible structure that kmalloc may ever be used for, just in case we have to inspect some data structure that could have been overwritten by something else ;) But seriously... you can always cast a page to a slub_page to see if it is unexpectedly a slub page.