Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964784AbXALRdq (ORCPT ); Fri, 12 Jan 2007 12:33:46 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964801AbXALRdq (ORCPT ); Fri, 12 Jan 2007 12:33:46 -0500 Received: from ebiederm.dsl.xmission.com ([166.70.28.69]:56577 "EHLO ebiederm.dsl.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964784AbXALRdp (ORCPT ); Fri, 12 Jan 2007 12:33:45 -0500 From: ebiederm@xmission.com (Eric W. Biederman) To: Dan Aloni Cc: Linux Kernel List Subject: Re: kexec + ACPI in 2.6.19 (was: Re: kexec + USB storage in 2.6.19) References: <20070112122444.GA28597@localdomain> <20070112145710.GA29884@localdomain> <20070112160243.GA13980@localdomain> <20070112162800.GA23791@localdomain> <20070112164339.GA24291@localdomain> <20070112165600.GB24291@localdomain> Date: Fri, 12 Jan 2007 10:33:34 -0700 In-Reply-To: <20070112165600.GB24291@localdomain> (Dan Aloni's message of "Fri, 12 Jan 2007 18:56:00 +0200") Message-ID: User-Agent: Gnus/5.110006 (No Gnus v0.6) Emacs/21.4 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2408 Lines: 65 Dan Aloni writes: > On Fri, Jan 12, 2007 at 06:43:40PM +0200, Dan Aloni wrote: >> On Fri, Jan 12, 2007 at 06:28:00PM +0200, Dan Aloni wrote: >> > On Fri, Jan 12, 2007 at 06:02:43PM +0200, Dan Aloni wrote: >> > > On Fri, Jan 12, 2007 at 08:26:03AM -0700, Eric W. Biederman wrote: >> > > > Dan Aloni writes: >> > > > >> > > > > I'm attaching the full logs. >> > > > >> > > > Thanks. >> > > > >> > > > > [ 8656.272980] ACPI Error (tbxfroot-0512): Could not map memory at > 0000040E for length 2 [20060707] >> > > > >> > > > Ok. This looks like the first sign of trouble. >> > > > Normally I would suspect a memory map issue but your e820 memory map > looks fine, >> > > > although a little different between the two kernels. >> > > > >> > > > Is this enough of a hint for you to dig more deeply? >> > > >> > > Reverting just the ACPI code (everything under drivers/acpi/*) >> > > back to the version of 2.6.18.3 doesn't fix the problem, so it >> > > must be something else. >> > >> > Just occured to me that I didn't revert the relevant code under >> > arch/x86_64 so it might still be related somehow.. >> >> After adding a few prints inside __ioremap() it appears the function >> exits for phys_addr==0x40e because (!PageReserved(page)). >> >> Isn't page 0 supposed to be reserved? I clearly see that it is >> being reserved under setup_arch(). >> >> Odd, I must say... > > In __ioremap() I added this under if(!PageReserved(page)) {...}: > > if (phys_addr == 0x40e) { > printk("PAGE %p (pfn=%ld): flags=%lx, count=%d\n", > page, > page_to_pfn(page), > page->flags, > atomic_read(&page->_count)); > } > > And I get: > > [ 1013.864201] PAGE ffff810001000000 (pfn=0): flags=0, count=0 > > So at least no one is using that page. Still it is not clear why it > doesn't have the reserve flag turned on. My hunch is that it might have something to do with the difference in the e820 map. The original map reports that whole page as being usable while in the kexec case the memory from 0x100 is reported as being usable. Perhaps someone has a rounding error? Eric - 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/