From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753504AbYAPPmj (ORCPT ); Wed, 16 Jan 2008 10:42:39 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751477AbYAPPma (ORCPT ); Wed, 16 Jan 2008 10:42:30 -0500 Received: from public.id2-vpn.continvity.gns.novell.com ([195.33.99.129]:28697 "EHLO public.id2-vpn.continvity.gns.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751400AbYAPPma convert rfc822-to-8bit (ORCPT ); Wed, 16 Jan 2008 10:42:30 -0500 Message-Id: <478E3411.76E4.0078.0@novell.com> X-Mailer: Novell GroupWise Internet Agent 7.0.2 HP Date: Wed, 16 Jan 2008 15:42:57 +0000 From: "Jan Beulich" To: "Ingo Molnar" , "Andi Kleen" Cc: "Glauber de Oliveira Costa" , "Jeremy Fitzhardinge" , "LKML" Subject: Re: [PATCH 0 of 4] x86: some more patches References: <200801161544.15884.ak@suse.de> <20080116145427.GA640@elte.hu> <200801161626.01711.ak@suse.de> In-Reply-To: <200801161626.01711.ak@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8BIT Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >Yes, but if you cast to long the result will be 32bit again. Or do you >rely on it being always used in 64bit signed context with sign extension? >While that might work it would seem rather fragile to me, just asking >for similar future bugs. Even if conversion is to 64-bit unsigned, the value (being signed) will be sign-extended first (to preserve its value modulo 2**). Jan