Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753119AbYLCUHw (ORCPT ); Wed, 3 Dec 2008 15:07:52 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753657AbYLCTwz (ORCPT ); Wed, 3 Dec 2008 14:52:55 -0500 Received: from kroah.org ([198.145.64.141]:60057 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752674AbYLCTwv (ORCPT ); Wed, 3 Dec 2008 14:52:51 -0500 Date: Wed, 3 Dec 2008 11:51:23 -0800 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: Justin Forbes , Zwane Mwaikambo , "Theodore Ts'o" , Randy Dunlap , Dave Jones , Chuck Wolber , Chris Wedgwood , Michael Krufky , Chuck Ebbert , Domenico Andreoli , Willy Tarreau , Rodrigo Rubira Branco , Jake Edge , Eugene Teo , torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Ian Campbell , Ingo Molnar , Jeremy Fitzhardinge Subject: [patch 044/104] xen: do not reserve 2 pages of padding between hypervisor and fixmap. Message-ID: <20081203195123.GS8950@kroah.com> References: <20081203193901.715896543@mini.kroah.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline; filename="xen-do-not-reserve-2-pages-of-padding-between-hypervisor-and-fixmap.patch" In-Reply-To: <20081203194725.GA8950@kroah.com> User-Agent: Mutt/1.5.16 (2007-06-09) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1841 Lines: 50 2.6.27-stable review patch. If anyone has any objections, please let us know. ------------------ From: Ian Campbell commit 5dc64a3442b98eaa0e3730c35fcf00cf962a93e7 upstream. When reserving space for the hypervisor the Xen paravirt backend adds an extra two pages (this was carried forward from the 2.6.18-xen tree which had them "for safety"). Depending on various CONFIG options this can cause the boot time fixmaps to span multiple PMDs which is not supported and triggers a WARN in early_ioremap_init(). This was exposed by 2216d199b1430d1c0affb1498a9ebdbd9c0de439 which moved the dmi table parsing earlier. x86: fix CONFIG_X86_RESERVE_LOW_64K=y The bad_bios_dmi_table() quirk never triggered because we do DMI setup too late. Move it a bit earlier. There is no real reason to reserve these two extra pages and the fixmap already incorporates FIX_HOLE which serves the same purpose. None of the other callers of reserve_top_address do this. Signed-off-by: Ian Campbell Signed-off-by: Ingo Molnar Cc: Jeremy Fitzhardinge Signed-off-by: Greg Kroah-Hartman --- arch/x86/xen/enlighten.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -1413,7 +1413,7 @@ static void __init xen_reserve_top(void) if (HYPERVISOR_xen_version(XENVER_platform_parameters, &pp) == 0) top = pp.virt_start; - reserve_top_address(-top + 2 * PAGE_SIZE); + reserve_top_address(-top); #endif /* CONFIG_X86_32 */ } -- 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/