From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756098Ab3L2CiG (ORCPT ); Sat, 28 Dec 2013 21:38:06 -0500 Received: from terminus.zytor.com ([198.137.202.10]:39677 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753427Ab3L2CiD (ORCPT ); Sat, 28 Dec 2013 21:38:03 -0500 Message-ID: <52BF8AEE.6020904@zytor.com> Date: Sat, 28 Dec 2013 18:37:34 -0800 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.2.0 MIME-Version: 1.0 To: halfdog , Thomas Gleixner , Ingo Molnar CC: x86@kernel.org, linux-kernel@vger.kernel.org Subject: Re: Sanitize CPU-state when switching from virtual-8086 mode to other task References: <52BF4A80.3010503@halfdog.net> In-Reply-To: <52BF4A80.3010503@halfdog.net> X-Enigmail-Version: 1.6 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/28/2013 02:02 PM, halfdog wrote: > It seems that missing CPU-state sanitation during task switching > triggers kernel-panic. This might be related to unhandled > FPU-errors. See [1] for POC and serial console log of OOPs. Due to > missing real 32-bit x86-hardware it is not clear, if this issue > might be related to subtle differences in virtual-8086 mode > handling when inside a virtualbox guest. > This oops happens inside the guest? Either way, I would be *very* skeptical of Virtualbox in this case. You can run a 32-bit kernel on 64-bit hardware, you know... -hpa