NOVA, NUL, snapshotting

Sartakov A. Vasily sartakov at
Fri Aug 23 13:13:35 CEST 2013


> On Thu, 18 Jul 2013 18:30:46 +0400 Sartakov A. Vasily (SAV) wrote:
> SAV> I have a question about VMCS. How to obtain VMCS data for migration?
> SAV> After creation of new VM, migration process should somehow give a
> SAV> context of transferring machine to NOVA, am I right?
> User code does not have to care about the details of VMCS/VMCB layout.
> Transfer of guest state to/from the microhypervisor happens by means of
> the UTCB data area as described in Sections 7.3 and 8.3 of the NOVA
> specification. In fact, user code is never given direct access to the
> VMCS/VMCB in order to prevent modification of host state.

Could you please describe how to get access to a context of virtual machine? 
How can I modify context of virtual machine from Vancouver? 
When system switches into Vancouver, for example by pressing a special keyboard key, where is stored context of VM? in allocated VMCB? Can I read and modify its from Vancouver?

Thank you.

Sartakov A. Vasily
sartakov at

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