From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964938AbWBTQBL (ORCPT ); Mon, 20 Feb 2006 11:01:11 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964941AbWBTQBL (ORCPT ); Mon, 20 Feb 2006 11:01:11 -0500 Received: from pentafluge.infradead.org ([213.146.154.40]:57835 "EHLO pentafluge.infradead.org") by vger.kernel.org with ESMTP id S964940AbWBTQBJ (ORCPT ); Mon, 20 Feb 2006 11:01:09 -0500 Date: Mon, 20 Feb 2006 16:00:54 +0000 From: Christoph Hellwig To: Ian Kent Cc: Andrew Morton , Kernel Mailing List , linux-fsdevel , autofs mailing list Subject: Re: [PATCH] autofs4 - fix comms packet struct size Message-ID: <20060220160054.GA31797@infradead.org> Mail-Followup-To: Christoph Hellwig , Ian Kent , Andrew Morton , Kernel Mailing List , linux-fsdevel , autofs mailing list References: <20060219141517.GA7942@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.1i X-SRS-Rewrite: SMTP reverse-path rewritten from by pentafluge.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Feb 20, 2006 at 09:05:59AM +0800, Ian Kent wrote: > > > autofs_wqt_t wait_queue_token; > > > > Hiding types in user visible structures behind typedefs is bad. > > What type is behind this? If this is not an __u32 you have > > a padding issue. > > This has been an occassion problem for a long time. > Since it dates back to way before version 4 I have always been reluctant > to change it. I'd rather leave it as is unless you really can't accept it. So is this an __u32? ;-) > OK. But will they be 32 bit for the life of this struct? If we'd ever bump pid_t or uid_t to 64bits tons of kernel interface would need to change. And no one guarantees it'd be come an u64 then. So __u32 is the safest choice.