From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262126AbUBREEu (ORCPT ); Tue, 17 Feb 2004 23:04:50 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262686AbUBREEu (ORCPT ); Tue, 17 Feb 2004 23:04:50 -0500 Received: from delerium.kernelslacker.org ([81.187.208.145]:2466 "EHLO delerium.codemonkey.org.uk") by vger.kernel.org with ESMTP id S262126AbUBREEk (ORCPT ); Tue, 17 Feb 2004 23:04:40 -0500 Date: Wed, 18 Feb 2004 04:01:30 +0000 From: Dave Jones To: Benjamin Herrenschmidt Cc: Santiago Leon , Linux Kernel list , Jeff Garzik Subject: Re: [PATCH][2.6] IBM PowerPC Virtual Ethernet Driver Message-ID: <20040218040130.GC26304@redhat.com> Mail-Followup-To: Dave Jones , Benjamin Herrenschmidt , Santiago Leon , Linux Kernel list , Jeff Garzik References: <40329A24.5070209@us.ibm.com> <1077065118.1082.83.camel@gaston> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1077065118.1082.83.camel@gaston> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Feb 18, 2004 at 11:45:20AM +1100, Benjamin Herrenschmidt wrote: > BITFIELDS ARE EVIL !!! > > Especially when mapping things like HW registers... I know the p/iSeries > code is full of them, I'd strongly recommend getting rid of them. > > The compiler is perfectly free, afaik, to re-order them That can't be right surely ? That would make them utterly useless afaics. I've not seen this happen in practice either with the 2 x86 cpufreq drivers I wrote that both use bitfields extensively. Dave