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Date: Tue, 29 Oct 2013 13:34:34 +0200
From: Gleb Natapov <gleb@redhat.com>
Message-ID: <20131029113434.GA16561@redhat.com>
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Subject: Re: [Qemu-devel] Prohibit Windows from running in QEMU
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To: Peter Lieven <pl@kamp.de>
Cc: "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, "Michael S. Tsirkin" <mst@redhat.com>

On Tue, Oct 29, 2013 at 12:31:18PM +0100, Peter Lieven wrote:
> On 29.10.2013 12:26, Gleb Natapov wrote:
> >On Tue, Oct 29, 2013 at 01:13:24PM +0200, Michael S. Tsirkin wrote:
> >>On Tue, Oct 29, 2013 at 10:48:07AM +0100, Peter Lieven wrote:
> >>>Hi all,
> >>>
> >>>this question might seem a bit weird, but does anyone see a good way to avoid
> >>>that Windows is able to boot inside qemu?
> >>>
> >>>We have defined several profiles for different operation systems and I want
> >>>to avoid that someone chooses Linux and then installs Windows within
> >>>a VM. Reason is licensing.
> >>>
> >>>Thanks,
> >>>Peter
> >>- create a device
> >>- write a linux driver
> >>- if driver is not enabled crash guest
> >>
> >For how long to wait before a crash?
> I would not like to alter the software in the guest anyway. If this would be required
> I could force a Linux version that would search for the alternate KVM signature
> in the cpuid leaf.
> 
You can detect certain patterns of RTC usage (Linux does not use it
usually), but it is fragile since Linux allows userspace to access RTC
and it may create the same usage pattern.

--
			Gleb.