[Qemu-devel] Re: [PATCH] balloon: Do not save VM state wrt asynchronous virtio operations

[Juan Quintela]

Adam Litke <address@hidden> wrote:
> When working with the VM state (for loadvm/savevm and migration), it is not
> valid to load and store pointers since the validity of those pointers cannot 
> be
> assured in the new qemu address space.  Therefore, virtio_balloon_save() and
> virtio_balloon_load() must not handle the stats-related fields in struct
> VirtIOBalloon.
>
> If a memory stats request is in-flight at the time of a migration or savevm,
> the request will not complete and should be resubmitted once migration or
> loadvm completes.  Note that this extremely small race window can only be
> triggered using QMP so it is not possible to hang the user monitor.
>     
> Signed-off-by: Adam Litke <address@hidden>

Acked-by: Juan Quintela <address@hidden>