Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757394AbYJJKWF (ORCPT ); Fri, 10 Oct 2008 06:22:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752775AbYJJKVy (ORCPT ); Fri, 10 Oct 2008 06:21:54 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:37592 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752303AbYJJKVx (ORCPT ); Fri, 10 Oct 2008 06:21:53 -0400 Date: Fri, 10 Oct 2008 12:21:28 +0200 From: Ingo Molnar To: Alan Cox Cc: Greg KH , stable@kernel.org, torvalds@osdl.org, Andrew Morton , linux-kernel@vger.kernel.org, Yinghai Lu Subject: Re: [PATCH RESEND] early_ioremap has a fencepost error Message-ID: <20081010102128.GA22856@elte.hu> References: <20081003195436.GA13506@Krystal> <20081004152456.GB23398@mit.edu> <20081006040820.GB26148@kroah.com> <20081010093901.GC13996@elte.hu> <20081010104645.139704c0@lxorguk.ukuu.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20081010104645.139704c0@lxorguk.ukuu.org.uk> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00,DNS_FROM_SECURITYSAGE autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] 0.0 DNS_FROM_SECURITYSAGE RBL: Envelope sender in blackholes.securitysage.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1903 Lines: 58 * Alan Cox wrote: > Can we get this into 2.6.27.x at some point as its a regression and a > crash on boot for some users moving from 2.6.26 yes, have your fix patch from yesterday in tip/x86/urgent already, with a stable@kernel.org tag included as well - see below. Thanks Alan! Ingo --------------> >From dd5698f42a5f2b494c3e811598403f105b00f4f2 Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Fri, 10 Oct 2008 10:46:45 +0100 Subject: [PATCH] x86, early_ioremap: fix fencepost error The x86 implementation of early_ioremap has an off by one error. If we get an object which ends on the first byte of a page we undermap by one page and this causes a crash on boot with the ASUS P5QL whose DMI table happens to fit this alignment. The size computation is currently last_addr = phys_addr + size - 1; npages = (PAGE_ALIGN(last_addr) - phys_addr) (Consider a request for 1 byte at alignment 0...) Closes #11693 Debugging work by Ian Campbell/Felix Geyer Signed-off-by: Alan Cox Cc: Signed-off-by: Ingo Molnar --- arch/x86/mm/ioremap.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c index d4b6e6a..d0975fc 100644 --- a/arch/x86/mm/ioremap.c +++ b/arch/x86/mm/ioremap.c @@ -595,7 +595,7 @@ void __init *early_ioremap(unsigned long phys_addr, unsigned long size) */ offset = phys_addr & ~PAGE_MASK; phys_addr &= PAGE_MASK; - size = PAGE_ALIGN(last_addr) - phys_addr; + size = PAGE_ALIGN(last_addr + 1) - phys_addr; /* * Mappings have to fit in the FIX_BTMAP area. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/