[PATCH V2 04/10] migration: preserve suspended for snapshot

[Steve Sistare]

Restoring a snapshot can break a suspended guest.

If a guest is suspended and saved to a snapshot using savevm, and qemu
is terminated and restarted with the -S option, then loadvm does not
restore the guest.  The runstate is running, but the guest is not, because
vm_start was not called.  The root cause is that loadvm does not restore
the runstate (eg suspended) from global_state loaded from the state file.

Restore the runstate, and allow the new state transitions that are possible.

Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
---
 migration/savevm.c | 1 +
 softmmu/runstate.c | 2 ++
 2 files changed, 3 insertions(+)

diff --git a/migration/savevm.c b/migration/savevm.c
index e0f4972..972d183 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -3139,6 +3139,7 @@ bool load_snapshot(const char *name, const char *vmstate,
     }
     aio_context_acquire(aio_context);
     ret = qemu_loadvm_state(f);
+    migrate_set_runstate();
     migration_incoming_state_destroy();
     aio_context_release(aio_context);
 
diff --git a/softmmu/runstate.c b/softmmu/runstate.c
index 5bbb22a..18efe31 100644
--- a/softmmu/runstate.c
+++ b/softmmu/runstate.c
@@ -77,6 +77,8 @@ typedef struct {
 
 static const RunStateTransition runstate_transitions_def[] = {
     { RUN_STATE_PRELAUNCH, RUN_STATE_INMIGRATE },
+    { RUN_STATE_PRELAUNCH, RUN_STATE_PAUSED },
+    { RUN_STATE_PRELAUNCH, RUN_STATE_SUSPENDED },
 
     { RUN_STATE_DEBUG, RUN_STATE_RUNNING },
     { RUN_STATE_DEBUG, RUN_STATE_FINISH_MIGRATE },
-- 
1.8.3.1