From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756405AbZAMWpe (ORCPT ); Tue, 13 Jan 2009 17:45:34 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751333AbZAMWpW (ORCPT ); Tue, 13 Jan 2009 17:45:22 -0500 Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:37414 "EHLO sunset.davemloft.net" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751243AbZAMWpU (ORCPT ); Tue, 13 Jan 2009 17:45:20 -0500 Date: Tue, 13 Jan 2009 14:45:21 -0800 (PST) Message-Id: <20090113.144521.97357573.davem@davemloft.net> To: kosaki.motohiro@jp.fujitsu.com Cc: Jesper.Nilsson@axis.com, tj@kernel.org, gregkh@suse.de, stern@rowland.harvard.edu, jens.axboe@oracle.com, hinko.kocevar@cetrtapot.si, linux-kernel@vger.kernel.org Subject: Re: lib/klist.c: bit 0 in pointer can't be used as flag From: David Miller In-Reply-To: <2f11576a0901131440w7fd3290uc9664aaf7aa89b08@mail.gmail.com> References: <20090113.131030.207355839.davem@davemloft.net> <20090113221235.GD19262@axis.com> <2f11576a0901131440w7fd3290uc9664aaf7aa89b08@mail.gmail.com> X-Mailer: Mew version 6.1 on Emacs 22.1 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: KOSAKI Motohiro Date: Wed, 14 Jan 2009 07:40:19 +0900 > > It may be that we've worked around the other spots, although I haven't > > seen anything like that, we might just have been lucky until now. > > > > Can you recall another place where this trick is used? > > rmap. > Don't CRIS use mmu? I'm beginning to suspect the issue is only with objects in the kernel image itself. Dynamically allocated memory is properly aligned and therefore the "low bit status bits in pointer" trick works.