From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758919AbZCOGVd (ORCPT ); Sun, 15 Mar 2009 02:21:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751960AbZCOGVY (ORCPT ); Sun, 15 Mar 2009 02:21:24 -0400 Received: from hera.kernel.org ([140.211.167.34]:38922 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751838AbZCOGVX (ORCPT ); Sun, 15 Mar 2009 02:21:23 -0400 Message-ID: <49BC9E14.4000005@kernel.org> Date: Sat, 14 Mar 2009 23:20:04 -0700 From: Yinghai Lu User-Agent: Thunderbird 2.0.0.19 (X11/20081227) MIME-Version: 1.0 To: Ingo Molnar CC: mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, tglx@linutronix.de, linux-tip-commits@vger.kernel.org Subject: Re: [tip:x86/mm] x86: make e820_update_range() handle small range update References: <49B9F0C1.10402@kernel.org> <20090314121705.GA13685@elte.hu> <49BBF59D.7060401@kernel.org> <20090314184010.GA17695@elte.hu> <49BC2279.2030101@kernel.org> <20090315060456.GF20949@elte.hu> In-Reply-To: <20090315060456.GF20949@elte.hu> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Ingo Molnar wrote: > * Yinghai Lu wrote: > >> Ingo Molnar wrote: >>> * Yinghai Lu wrote: >>> >>>> Ingo Molnar wrote: >>>>> * Yinghai Lu wrote: >>>>> >>>>>> Commit-ID: 78a8b35bc7abf8b8333d6f625e08c0f7cc1c3742 >>>>>> Gitweb: http://git.kernel.org/tip/78a8b35bc7abf8b8333d6f625e08c0f7cc1c3742 >>>>>> Author: Yinghai Lu >>>>>> AuthorDate: Thu, 12 Mar 2009 22:36:01 -0700 >>>>>> Commit: Ingo Molnar >>>>>> CommitDate: Sat, 14 Mar 2009 12:20:07 +0100 >>>>>> >>>>>> x86: make e820_update_range() handle small range update >>>>>> >>>>>> Impact: enhance e820 code to handle more cases >>>>>> >>>>>> Try to handle new range which could be covered by one entry. >>>>>> >>>>>> Signed-off-by: Yinghai Lu >>>>>> Cc: jbeulich@novell.com >>>>>> LKML-Reference: <49B9F0C1.10402@kernel.org> >>>>>> Signed-off-by: Ingo Molnar >>>>> -tip testing found a bootup crash + reboot due to this patch. >>>>> >>>>> config attached. The bootup crashes here: >>>>> >>>>> [ 0.000000] MTRR variable ranges enabled: >>>>> [ 0.000000] 0 base 0000000000 mask FFC0000000 write-back >>>>> [ 0.000000] 1 disabled >>>>> [ 0.000000] 2 disabled >>>>> [ 0.000000] 3 disabled >>>>> [ 0.000000] 4 disabled >>>>> [ 0.000000] 5 disabled >>>>> [ 0.000000] 6 disabled >>>>> [ 0.000000] 7 disabled >>>>> [ 0.000000] x86 PAT enabled: cpu 0, old 0x7040600070406, new 0x7010600070106 >>>>> [ 0.000000] get_mtrr: cpu0 reg00 base=0000000000 size=0000040000 write-back >>>>> [ reboot ] >>>>> >>>> what does the e820 map look like? >>> [ 0.000000] BIOS-provided physical RAM map: >>> [ 0.000000] BIOS-e820: 0000000000000000 - 000000000009f800 (usable) >>> [ 0.000000] BIOS-e820: 000000000009f800 - 00000000000a0000 (reserved) >>> [ 0.000000] BIOS-e820: 00000000000f0000 - 0000000000100000 (reserved) >>> [ 0.000000] BIOS-e820: 0000000000100000 - 000000003fff0000 (usable) >>> [ 0.000000] BIOS-e820: 000000003fff0000 - 000000003fff3000 (ACPI NVS) >>> [ 0.000000] BIOS-e820: 000000003fff3000 - 0000000040000000 (ACPI data) >>> [ 0.000000] BIOS-e820: 00000000e0000000 - 00000000f0000000 (reserved) >>> [ 0.000000] BIOS-e820: 00000000fec00000 - 0000000100000000 (reserved) >>> >> it seems that patch revealed the bug in >> setup_bios_corruption_check > > Cool. I'm wondering, could this explain: > > http://bugzilla.kernel.org/show_bug.cgi?id=12645 > i wonder if we need to add print out about range from e820_update_range() or add sth like boundary checking in e820_update_range() to stop crazy calling? YH