From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([208.118.235.92]:54553)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <stefanha@redhat.com>) id 1UFjrp-0005wn-Ns
	for qemu-devel@nongnu.org; Wed, 13 Mar 2013 07:29:19 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <stefanha@redhat.com>) id 1UFjra-0002Yc-Bw
	for qemu-devel@nongnu.org; Wed, 13 Mar 2013 07:29:09 -0400
Received: from mx1.redhat.com ([209.132.183.28]:6492)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <stefanha@redhat.com>) id 1UFjra-0002Xw-2L
	for qemu-devel@nongnu.org; Wed, 13 Mar 2013 07:28:54 -0400
Date: Wed, 13 Mar 2013 12:28:46 +0100
From: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20130313112846.GA25354@stefanha-thinkpad.muc.redhat.com>
References: <CAOZVR5apRncULS9M59pNka5OwA6hdW0tyyY_AfhhGBzOF=d9Lw@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <CAOZVR5apRncULS9M59pNka5OwA6hdW0tyyY_AfhhGBzOF=d9Lw@mail.gmail.com>
Subject: Re: [Qemu-devel] dataplane bug: fail to start VM with dataplane
	enable
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Dunrong Huang <riegamaths@gmail.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>, qemu-devel <qemu-devel@nongnu.org>

On Wed, Mar 13, 2013 at 06:01:40PM +0800, Dunrong Huang wrote:
> Hi,  Paolo && Stefan:
> 
> When I test the dataplane feature with git master, I find that VM will
> hang if dataplane is enabled. But if I use qemu-1.4.0, VM can start
> normally.
> 
> The command I boot QEMU is:
> x86_64-softmmu/qemu-system-x86_64 -enable-kvm -m 1024 -smp 2 -drive
> file=centos-6.4.raw,if=none,id=drive-virtio-disk,format=raw,cache=none,aio=native
> -device virtio-blk-pci,config-wce=off,scsi=off,x-data-plane=on,drive=drive-virtio-disk,id=virtio-disk
> 
> git bisect implicates this bug was introduced by following commit:
> 
> commit 82959e8262df7da882d715f8a0cb4e8c7cd6e94b
> Author: Paolo Bonzini <pbonzini@redhat.com>
> Date:   Fri Feb 22 10:40:34 2013 +0100
> 
>     dataplane: remove EventPoll in favor of AioContext

It reproduces here too using a RHEL 6.4 guest image.  Hang at the BIOS
screen before GRUB is loaded.

Stefan