On 22.08.2010, at 18:42, Avi Kivity wrote:

On 08/17/2010 04:57 PM, Alexander Graf wrote:

quoted

We will soon add SR PV support to the shared page, so we need some
infrastructure that allows the guest to query for features KVM =

exports.

quoted

=20
This patch adds a second return value to the magic mapping that
indicated to the guest which features are available.
=20

=20
You need to make that feature controllable from userspace, to allow =

new->old save/restore.

Good one :). We're still missing too much stuff to even run without =
losing interrupts yet and you're thinking about new->old save/restore. =
Who'd want to migrate onto a system that's broken anyways? Besides - =
we're missing too many register values from the kernel side to even be =
able to perform a migration.

I'm planning to add migration, probably after SMP. But that will be =
another CAP and anything before that won't be able to save/restore.


Alex