Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936497AbYBUXyr (ORCPT ); Thu, 21 Feb 2008 18:54:47 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S935951AbYBUXtk (ORCPT ); Thu, 21 Feb 2008 18:49:40 -0500 Received: from gw.goop.org ([64.81.55.164]:40466 "EHLO mail.goop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759078AbYBUXth (ORCPT ); Thu, 21 Feb 2008 18:49:37 -0500 Message-ID: <47BE0D70.2020009@goop.org> Date: Thu, 21 Feb 2008 15:46:56 -0800 From: Jeremy Fitzhardinge User-Agent: Thunderbird 2.0.0.9 (X11/20071115) MIME-Version: 1.0 To: "H. Peter Anvin" CC: "Eric W. Biederman" , Ian Campbell , Joel Becker , Jody Belka , linux-kernel@vger.kernel.org, Ingo Molnar , Thomas Gleixner , Andi Kleen , Mika Penttila Subject: Re: 2.6.25-rc1 xen pvops regression References: <20080212235404.GY7980@pimb.org> <47B2DBA5.6030001@goop.org> <20080214022744.GA4160@mail.oracle.com> <47B3F2DC.8080707@goop.org> <20080215202336.GE26034@mail.oracle.com> <1203274161.27987.6.camel@localhost.localdomain> <20080218104025.GA15899@ca-server1.us.oracle.com> <1203458366.26910.15.camel@cthulhu.hellion.org.uk> <47BBDA20.8030105@zytor.com> <1203497511.26910.39.camel@cthulhu.hellion.org.uk> <47BCA275.7000504@goop.org> <1203546597.26910.74.camel@cthulhu.hellion.org.uk> <47BDEA11.6010302@goop.org> <47BDEB57.5040203@zytor.com> <47BE05C0.2090405@goop.org> <47BE08C0.5060700@zytor.com> In-Reply-To: <47BE08C0.5060700@zytor.com> X-Enigmail-Version: 0.95.6 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 Content-Length: 941 Lines: 26 H. Peter Anvin wrote: > Jeremy Fitzhardinge wrote: >> >> It seems to me that those pages are being handed out as heap pages by >> the early allocator. In the Xen case this is OK because there's >> nothing magic about them. But if real hardware doesn't reserve these >> pages in the E820 map, then they could end up being used as regular >> memory by mistake, which is an issue. >> > > No, they couldn't. > > On real hardware they'll be memory types 0 or 2, depending on whether > or not they're marked reserved. > > Available RAM is type 1. OK. Well, perhaps Ian's patch could be amended to test to see if the e820 map marks the ISA ROM region as normal RAM, and skip it if so? J -- 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/