Re: [PATCH V2 02/10] migration: preserve suspended runstate

[Fabiano Rosas <farosas@suse.de>]

Steve Sistare <steven.sistare@oracle.com> writes:

> A guest that is migrated in the suspended state automaticaly wakes and
> continues execution.  This is wrong; the guest should end migration in
> the same state it started.  The root causes is that the outgoing migration
> code automatically wakes the guest, then saves the RUNNING runstate in
> global_state_store(), hence the incoming migration code thinks the guest is
> running and continues the guest if autostart is true.
>
> On the outgoing side, do not call qemu_system_wakeup_request().  That
> alone fixes precopy migration, as process_incoming_migration_bh correctly
> sets runstate from global_state_get_runstate().
>
> On the incoming side for postcopy, do not wake the guest, and apply the
> the same logic as found in precopy: if autostart and the runstate is
> RUNNING, then vm_start, else merely restore the runstate.
>
> In both cases, if the restored state is SUSPENDED, then a later wakeup
> request will resume the guest, courtesy of the previous "start on wakeup"
> patch.
>
> Signed-off-by: Steve Sistare <steven.sistare@oracle.com>

Reviewed-by: Fabiano Rosas <farosas@suse.de>