From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754314Ab0I0FbR (ORCPT ); Mon, 27 Sep 2010 01:31:17 -0400 Received: from one.firstfloor.org ([213.235.205.2]:34029 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753590Ab0I0FbP (ORCPT ); Mon, 27 Sep 2010 01:31:15 -0400 Date: Mon, 27 Sep 2010 07:31:10 +0200 From: Andi Kleen To: huang ying Cc: Andi Kleen , Huang Ying , Len Brown , linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org Subject: Re: [PATCH 5/5] ACPI, APEI, Fix ERST MOVE_DATA instruction implementation Message-ID: <20100927053110.GA21952@one.firstfloor.org> References: <1284865235-29920-1-git-send-email-ying.huang@intel.com> <1284865235-29920-6-git-send-email-ying.huang@intel.com> <20100921124718.GE18991@one.firstfloor.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.2i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > In my test machine, MOVE_DATA is not used. So this does not breaks > serialization of machine checks. Ok. But we don't know what other systems are doing. > > We can not use kmap_atomic or kmap_atomic_pfn here. Because > kmap_atomic_xxx needs struct page, but the address provided by BIOS > may be in E820_RESERVED area, that is, the corresponding page may have > no struct page. Maybe we need another kmap_atomic implementation for > E820_RESERVED area. Yes, at some point that may be needed. It would be good to have some kind of warning that gets reported back to us when this happens. This should happen on panicing situations anyways, so we can printk. -Andi -- ak@linux.intel.com -- Speaking for myself only.