Return-path: Received: from deine-taler.de ([217.160.107.63]:49398 "EHLO p15091797.pureserver.info" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750988AbXCKULu (ORCPT ); Sun, 11 Mar 2007 16:11:50 -0400 Date: Sun, 11 Mar 2007 21:11:49 +0100 From: Ulrich Kunitz To: Johannes Berg Cc: jt@hpl.hp.com, Jouni Malinen , Michael Buesch , linux-wireless@vger.kernel.org, netdev , Jeff Garzik , Dan Williams Subject: Re: wireless extensions vs. 64-bit architectures Message-ID: <20070311201148.GA25938@p15091797.pureserver.info> References: <20070307020310.GA20466@bougret.hpl.hp.com> <1173364747.14001.7.camel@johannes.berg> <20070308184954.GA24485@bougret.hpl.hp.com> <1173382042.3248.63.camel@johannes.berg> <20070308193412.GG23040@devicescape.com> <1173382802.3248.68.camel@johannes.berg> <20070308221128.GA24884@bougret.hpl.hp.com> <1173393326.3831.21.camel@johannes.berg> <20070309213531.GA28070@bougret.hpl.hp.com> <1173634801.3382.8.camel@johannes.berg> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1173634801.3382.8.camel@johannes.berg> Sender: linux-wireless-owner@vger.kernel.org List-ID: > I'm still not convinced that papering over the problem in userspace is a > real solution. > > johannes Just my 2 cents. I support this. What are the options? I see only two: 1. Use different magic numbers for 32 bit and 64 bit structures. A flag is an alternative, but will be more difficult to debug. Generation of the magic should be easy, use sizeof(unsigned long) as test. User space has to care than for the rest. 2. Make the data representation identical in 32 bit and 64 bit. This shouldn't be to difficult, if only u8, u16 and u32 types are used. Pointers should be given as offsets. If necessary align and/or packed attributes could be used. If the kernel interface can be changed, I vote for option 2, because user space has then to deal with a unique data layout. If the wext kernel interface cannot be changed to maintain backward compatibility, then I have to admit band-aids in user space are needed. However cfg80211 must not suffer from the same issues. -- Uli Kunitz