From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760413AbZA3AKp (ORCPT ); Thu, 29 Jan 2009 19:10:45 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755031AbZA3AK0 (ORCPT ); Thu, 29 Jan 2009 19:10:26 -0500 Received: from smtp1.linux-foundation.org ([140.211.169.13]:56766 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759192AbZA3AKY (ORCPT ); Thu, 29 Jan 2009 19:10:24 -0500 Date: Thu, 29 Jan 2009 16:09:43 -0800 From: Andrew Morton To: "James Kirin" Cc: yinghai@kernel.org, rdreier@cisco.com, linux-kernel@vger.kernel.org Subject: Re: kernel panic when using disable_mtrr_trim [was: Re: memory beyond4GB invisible to the system even though CONFIG_HIGHMEM64G=y] Message-Id: <20090129160943.1bb0d3b5.akpm@linux-foundation.org> In-Reply-To: References: X-Mailer: Sylpheed version 2.2.4 (GTK+ 2.8.20; i486-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 20 Jan 2009 13:18:15 -0500 "James Kirin" wrote: > Hi Yinghai, > > When I boot with "disable_mtrr_trim mem=4g", the system boots fine. > Then I changed that to > "disable_mtrr_trim mem=6g" and a kernel panic occurs: > > [...] Freeing unused kernel memory: 296k freed > [...] Write protecting the kernel text: 3040k > [...] Write protecting the kernel read-only data: 1352k > [...] khelper used greatest stack depth: 6724 byytes left > [...] Kernel panic - not syncing: No init found. Try passing init= > option to kernel. > > I can always reproduce this: all it takes it to boot from a rescue CD, > switch between "mem=4g" and "mem=6g" in /etc/lilo.conf, run lilo and > reboot. If it is 4g, it boots fine; if it is 6g, a kernel panic > occurs. No other changes at all were made. > > Same thing (kernel panic) occurs if mem=5g is used. > > I am attaching the kernel config used when this happens. > > Please let me know how I can help fix this. Does it somehow depend on > all those MTRR/etc memory-related options in the kernel configuration? > Did this get fixed? Which kernel versions are affected? Thanks.