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Subject: Re: [Xen-devel] KVM PV
To: George Dunlap <george.dunlap@citrix.com>
Cc: Lai Jiangshan <jiangshanlai+lkml@gmail.com>,
        Juergen Gross <jgross@suse.com>, Rusty Russell <rusty@rustcorp.com.au>,
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From: Paolo Bonzini <pbonzini@redhat.com>
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Date: Mon, 2 Oct 2017 14:17:54 +0200
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On 02/10/2017 12:36, George Dunlap wrote:
>>> Although I'm not business man, I don't think the top cloud provider[s]
>>> would allow nested virtualization, however mature nested virtualization
>>> is. Even xen-pv is unable to be nested in the aws and azure.
>>
>> Check the contributors to KVM nested virtualization, you might be surprised.
>>
>> Nested Xen PV is not possible because the Xen hypervisor cannot run as a PV guest.>> It's a technical limitation.
> 
> Minor correction: Xen can't run on AWS as a PV guest, but it can run
> as an L1 hypervisor inside any "fully virtualized" VM (as both AWS and
> Azure provide), and provide PV L2 guests.

Yes, that's what I meant.

Thanks George!

Paolo