From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758573AbZEKJ6H (ORCPT ); Mon, 11 May 2009 05:58:07 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758165AbZEKJzm (ORCPT ); Mon, 11 May 2009 05:55:42 -0400 Received: from hera.kernel.org ([140.211.167.34]:49452 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757990AbZEKJzk (ORCPT ); Mon, 11 May 2009 05:55:40 -0400 Date: Mon, 11 May 2009 09:54:15 GMT From: tip-bot for Yinghai Lu To: linux-tip-commits@vger.kernel.org Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@redhat.com, yinghai@kernel.org, akpm@linux-foundation.org, mel@csn.ul.ie, tglx@linutronix.de, mingo@elte.hu Reply-To: mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, yinghai@kernel.org, akpm@linux-foundation.org, mel@csn.ul.ie, tglx@linutronix.de, mingo@elte.hu In-Reply-To: <4A03E13E.6050107@kernel.org> References: <4A03E13E.6050107@kernel.org> Subject: [tip:x86/mm] x86: Allow 1MB of slack between the e820 map and SRAT, not 4GB Message-ID: Git-Commit-ID: 0964b0562bb9c93194e852b47bab2397b9e11c18 X-Mailer: tip-git-log-daemon MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.0 (hera.kernel.org [127.0.0.1]); Mon, 11 May 2009 09:54:17 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 0964b0562bb9c93194e852b47bab2397b9e11c18 Gitweb: http://git.kernel.org/tip/0964b0562bb9c93194e852b47bab2397b9e11c18 Author: Yinghai Lu AuthorDate: Fri, 8 May 2009 00:37:34 -0700 Committer: Ingo Molnar CommitDate: Mon, 11 May 2009 11:38:21 +0200 x86: Allow 1MB of slack between the e820 map and SRAT, not 4GB It is expected that there might be slight differences between the e820 map and the SRAT table and the intention was that 1MB of slack be allowed. The calculation comparing e820ram and pxmram assumes the units are bytes, when they are in fact pages. This means 4GB of slack is being allowed, not 1MB. This patch makes the correct comparison. comment is from Mel. [ Impact: don't accept buggy SRATs that could dump up to 4G of RAM ] Signed-off-by: Yinghai Lu Acked-by: Mel Gorman Cc: Andrew Morton LKML-Reference: <4A03E13E.6050107@kernel.org> Signed-off-by: Ingo Molnar --- arch/x86/mm/srat_64.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/mm/srat_64.c b/arch/x86/mm/srat_64.c index c7a18aa..87b45bf 100644 --- a/arch/x86/mm/srat_64.c +++ b/arch/x86/mm/srat_64.c @@ -346,8 +346,8 @@ static int __init nodes_cover_memory(const struct bootnode *nodes) } e820ram = max_pfn - (e820_hole_size(0, max_pfn<>PAGE_SHIFT); - /* We seem to lose 3 pages somewhere. Allow a bit of slack. */ - if ((long)(e820ram - pxmram) >= 1*1024*1024) { + /* We seem to lose 3 pages somewhere. Allow 1M of slack. */ + if ((long)(e820ram - pxmram) >= (1<<(20 - PAGE_SHIFT))) { printk(KERN_ERR "SRAT: PXMs only cover %luMB of your %luMB e820 RAM. Not used.\n", (pxmram << PAGE_SHIFT) >> 20,