From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753863AbYFEH1r (ORCPT ); Thu, 5 Jun 2008 03:27:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751898AbYFEH1h (ORCPT ); Thu, 5 Jun 2008 03:27:37 -0400 Received: from sous-sol.org ([216.99.217.87]:52366 "EHLO sous-sol.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751509AbYFEH1g (ORCPT ); Thu, 5 Jun 2008 03:27:36 -0400 Date: Thu, 5 Jun 2008 00:27:28 -0700 From: Chris Wright To: Tobias Diedrich , Chris Wright , Avi Kivity , kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: kvm: unable to handle kernel NULL pointer dereference Message-ID: <20080605072728.GF30402@sequoia.sous-sol.org> References: <20080601084802.GA3146@yamamaya.is-a-geek.org> <4846716E.5000506@qumranet.com> <20080604181019.GB10897@yamamaya.is-a-geek.org> <20080605042535.GC30402@sequoia.sous-sol.org> <20080605060931.GA11704@yamamaya.is-a-geek.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080605060931.GA11704@yamamaya.is-a-geek.org> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Tobias Diedrich (ranma+kernel@tdiedrich.de) wrote: > Almost: > ranma@melchior:~/src/linux-2.6.26-rc4.forcedwol$ gdb -q vmlinux > Using host libthread_db library "/lib/libthread_db.so.1". > (gdb) p/x 0xffffffff8021d456 + 0x6f9cba > $1 = 0xffffffff80917110 > (gdb) p/x &per_cpu__svm_data > $2 = 0xffffffff809170f8 > (gdb) Sorry, my math was bad. I gave you 0xffffffff8021d44f + 7 + 0x6f9cba, but it should have been 0xffffffff8021d44f - 17 + 0x6f9cba. Which is correct (as one would hope, it was a grasp at straws). Oh, wait. Is this a laptop? Do you suspend/resume? Suspend will free svm_data, and on resume, any launching a guest will definitely hit the oops you are seeing. Do you ever see this in dmesg? svm_cpu_init: svm_data is NULL on 0 thanks, chris