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Date: Thu, 1 Aug 2013 16:32:14 +0300
From: "Michael S. Tsirkin" <mst@redhat.com>
Message-ID: <20130801133214.GA15659@redhat.com>
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Subject: Re: [Qemu-devel] pvpanic device should not be automatically
 included as an internal device
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To: Marcel Apfelbaum <marcel.a@redhat.com>
Cc: Hu Tao <hutao@cn.fujitsu.com>, Anthony Liguori <aliguori@us.ibm.com>, qemu-devel@nongnu.org, Markus Armbruster <armbru@redhat.com>

On Thu, Aug 01, 2013 at 04:08:57PM +0300, Marcel Apfelbaum wrote:
> Hi,
> 
> The problem with pvpanic being an internal device is that VMs running
> operating systems without a driver for this device will have problems
> when qemu will be upgraded (from qemu without this pvpanic).
> 
> The outcome may be, for example: in Windows(let's say XP) the Device manager
> will open a "new device" wizard and the device will appear as an unrecognized device.
> Now what will happen on a cluster with hundreds of such VMs? If that cluster has a health
> monitoring service it may show all the VMs in a "not healthy" state.
> 
> My point is that a device that requires a driver that is not "inbox", should not
> be present by default.
> One possible solution is to add it manually with -device from command line.
> 
> Any thoughts?
> Marcel

Interesting. You are basically saying we should have a rule
that no new builtin devices should be added
without an explicit request from management interface?


-- 
MST