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Date: Thu, 23 May 2013 15:32:19 +0200
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From: Stefan Hajnoczi <stefanha@gmail.com>
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Subject: Re: [Qemu-devel] qemu seabios issue with vhost-scsi
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To: Gleb Natapov <gleb@redhat.com>
Cc: Asias He <asias@redhat.com>, Badari <pbadari@us.ibm.com>, qemu-devel <qemu-devel@nongnu.org>, "Nicholas A. Bellinger" <nab@linux-iscsi.org>

On Thu, May 23, 2013 at 11:48 AM, Gleb Natapov <gleb@redhat.com> wrote:
> On Thu, May 23, 2013 at 08:53:55AM +0800, Asias He wrote:
>> On Wed, May 22, 2013 at 05:36:08PM -0700, Badari wrote:
>> > Hi,
>> >
>> > While testing vhost-scsi in the current qemu git, ran into an earlier issue
>> > with seabios. I had to disable scsi support in seabios to get it working.
>> >
>> > I was hoping this issue got resolved when vhost-scsi support got
>> > merged into qemu. Is this still being worked on ?
>>
>> Hmm, can you try seabios.git? Not sure if seabios shipped by qemu picked
>> up the fixes for vhost-scsi.
>>
> Nothing in seabios should crash qemu.

Agreed.  I'm pretty sure it's the scenario that I posted in my other
reply to this thread.

The common virtio-scsi code in QEMU should guard against this.  In
virtio-blk data plane I hit a similar case and ended up starting the
data plane thread (equivalent to vhost here) *before* the status
register is set to DRIVER_OK.

Stefan