From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750951AbXDCUuf (ORCPT ); Tue, 3 Apr 2007 16:50:35 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751042AbXDCUuf (ORCPT ); Tue, 3 Apr 2007 16:50:35 -0400 Received: from iona.labri.fr ([147.210.8.143]:59100 "EHLO iona.labri.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750907AbXDCUue (ORCPT ); Tue, 3 Apr 2007 16:50:34 -0400 Date: Mon, 2 Apr 2007 22:42:02 +0200 From: Samuel Thibault To: linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: mbind and alignment Message-ID: <20070402204202.GC3316@interface.famille.thibault.fr> Mail-Followup-To: Samuel Thibault , linux-kernel@vger.kernel.org, linux-mm@kvack.org MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.12-2006-07-14 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi, mbind(start, len, ...) currently requires that "start" be page-aligned, but not "len" (which automatically gets page-rounded up). This is a bit odd: - the userland type of start is void*, which people would expect to be a pointer to some variable. - start needing to be page-aligned but len not needing to is not very consistent. - none of this is documented in the manual page dated 2006-02-07 So one of those should probably be done to free people from headaches: - document "start" requirement in the manual page - require len to be aligned too, and document the requirements in the manual page - drop the "start" requirement and just round down the page + adjust size automatically. Samuel