From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760319AbZCPWkG (ORCPT ); Mon, 16 Mar 2009 18:40:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755527AbZCPWjz (ORCPT ); Mon, 16 Mar 2009 18:39:55 -0400 Received: from terminus.zytor.com ([198.137.202.10]:37657 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754589AbZCPWjy (ORCPT ); Mon, 16 Mar 2009 18:39:54 -0400 Message-ID: <49BED431.5070201@zytor.com> Date: Mon, 16 Mar 2009 15:35:29 -0700 From: "H. Peter Anvin" User-Agent: Thunderbird 2.0.0.19 (X11/20090105) MIME-Version: 1.0 To: Jeremy Fitzhardinge CC: Yinghai Lu , Ingo Molnar , Linux Kernel Mailing List Subject: Re: [crash] Re: Latest brk patchset References: <49BC413B.5020104@zytor.com> <49BC4CAC.202@goop.org> <49BC4DB6.9070403@zytor.com> <49BCA03D.3020605@goop.org> <20090315203802.GA14625@elte.hu> <49BD70EF.7010204@goop.org> <20090315212854.GA23960@elte.hu> <49BD8F15.4020301@goop.org> <20090316085402.GC1062@elte.hu> <49BE7A84.2030503@goop.org> <49BE84D6.3010006@kernel.org> <49BE9248.6050707@goop.org> <49BE97D5.4010002@zytor.com> <49BEA7BE.6050400@goop.org> <49BEAD27.3050801@kernel.org> <49BEAFEC.7020400@goop.org> <49BEB5FE.7050601@zytor.com> <49BEBD98.3090905@goop.org> <49BEC143.6030104@zytor.com> <49BEC53F.20200@goop.org> In-Reply-To: <49BEC53F.20200@goop.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Jeremy Fitzhardinge wrote: > H. Peter Anvin wrote: >> Or simplified: >> >> PAGE_TABLE_SIZE(((1 << 32)-PAGE_OFFSET) >> PAGE_SHIFT) << PAGE_SHIFT > > Was worried about 1<<32 overflowing. Never really sure what gas's type > system is. > It's bignum-based. You could also write: PAGE_TABLE_SIZE((-PAGE_OFFSET & 0xffffffff) >> PAGE_SHIFT) << PAGE_SHIFT (the & 0xffffffff is necessary, or you'll get a signed shift.) -hpa