On 08/31/2010 03:56 AM, Alexander Graf wrote:

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

quoted

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.

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

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.

I'm thinking stability and basic functionality and your running around 
adding features (or new archs, depending on mood).  But I agree, this 
can wait until after SMP.

-- 
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.