From petefrench@ingresso.co.uk  Thu May 24 10:43:48 2012
Return-Path: <petefrench@ingresso.co.uk>
Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52])
	by hub.freebsd.org (Postfix) with ESMTP id 0DC49106566B
	for <FreeBSD-gnats-submit@freebsd.org>; Thu, 24 May 2012 10:43:48 +0000 (UTC)
	(envelope-from petefrench@ingresso.co.uk)
Received: from constantine.ingresso.co.uk (constantine.ingresso.co.uk [IPv6:2a02:b90:3002:e550::3])
	by mx1.freebsd.org (Postfix) with ESMTP id 9A5198FC14
	for <FreeBSD-gnats-submit@freebsd.org>; Thu, 24 May 2012 10:43:47 +0000 (UTC)
Received: from dilbert.london-internal.ingresso.co.uk ([10.64.50.6] helo=dilbert.ingresso.co.uk)
	by constantine.ingresso.co.uk with esmtps (TLSv1:AES256-SHA:256)
	(Exim 4.76 (FreeBSD))
	(envelope-from <petefrench@ingresso.co.uk>)
	id 1SXVWE-0003Ry-Ed
	for FreeBSD-gnats-submit@freebsd.org; Thu, 24 May 2012 11:43:46 +0100
Received: from petefrench by dilbert.ingresso.co.uk with local (Exim 4.77 (FreeBSD))
	(envelope-from <petefrench@ingresso.co.uk>)
	id 1SXVWE-000GPM-Dx
	for FreeBSD-gnats-submit@freebsd.org; Thu, 24 May 2012 11:43:46 +0100
Message-Id: <E1SXVWE-000GPM-Dx@dilbert.ingresso.co.uk>
Date: Thu, 24 May 2012 11:43:46 +0100
From: Pete French <petefrench@ingresso.co.uk>
Reply-To: Pete French <petefrench@ingresso.co.uk>
To: FreeBSD-gnats-submit@freebsd.org
Cc:
Subject: VirtualBox using AIO on a zvol crashes
X-Send-Pr-Version: 3.113
X-GNATS-Notify:

>Number:         168298
>Category:       kern
>Synopsis:       VirtualBox using AIO on a zvol crashes
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:
>Keywords:
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Thu May 24 10:50:03 UTC 2012
>Closed-Date:
>Last-Modified:
>Originator:     Pete French
>Release:        FreeBSD 8.3-STABLE amd64
>Organization:
Ingresso Group Ltd
>Environment:
System: FreeBSD dilbert.london-internal.ingresso.co.uk 8.3-STABLE FreeBSD 8.3-STABLE #0: Sun May 6 14:15:46 BST 2012 petefrench@dilbert.london-internal.ingresso.co.uk:/usr/obj/usr/src/sys/GENERIC amd64

	virtualbox-ose-kmod-4.1.14

>Description:

	With AIO loaded ViryialBox will use this to access files. Running
	VirtualBox on to of a zvol as the raw disc crashes. This may be a bug
	in zvol+aio, hence the classification above. VirtualBox prduces an
	error message in it's logs about AIO before crashing.

>How-To-Repeat:

	Running VirtualBox over a zvol with AIO and then doing heavy
	disc write activity will provoke the problem in a few minutes. I made
	a posting to stable regarding this here:

	http://lists.freebsd.org/pipermail/freebsd-stable/2012-May/067648.html

	The zvol has compression enabled.
>Fix:

	Do not load the AIO kernel module. VirtualBox is stable if AIO
	is not being used.


>Release-Note:
>Audit-Trail:
>Unformatted:
