From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1945959AbXDCV1J (ORCPT ); Tue, 3 Apr 2007 17:27:09 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1945966AbXDCV1J (ORCPT ); Tue, 3 Apr 2007 17:27:09 -0400 Received: from mx1.redhat.com ([66.187.233.31]:44998 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1945959AbXDCV1G (ORCPT ); Tue, 3 Apr 2007 17:27:06 -0400 Message-ID: <4612C6A6.9020003@redhat.com> Date: Tue, 03 Apr 2007 17:27:02 -0400 From: Chuck Ebbert Organization: Red Hat User-Agent: Thunderbird 1.5.0.10 (X11/20070302) MIME-Version: 1.0 To: Samuel Thibault , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: mbind and alignment References: <20070402204202.GC3316@interface.famille.thibault.fr> In-Reply-To: <20070402204202.GC3316@interface.famille.thibault.fr> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Samuel Thibault wrote: > 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. > Want to help with man page maintenance? Grab the latest tarball at ftp://ftp.win.tue.nl/pub/linux-local/manpages/, read the HOWTOHELP file and grep the source files for 'FIXME'.