1 files changed, 16 insertions, 1 deletions
diff --git a/migration/migration.c b/migration/migration.c
index c597aa707e..1833cfe358 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -402,11 +402,24 @@ void migration_incoming_state_destroy(void)
     struct MigrationIncomingState *mis = migration_incoming_get_current();
 
     multifd_recv_cleanup();
+
     /*
      * RAM state cleanup needs to happen after multifd cleanup, because
      * multifd threads can use some of its states (receivedmap).
+     * The VFIO load_cleanup() implementation is BQL-sensitive. It requires
+     * BQL must NOT be taken when recycling load threads, so that it won't
+     * block the load threads from making progress on address space
+     * modification operations.
+     *
+     * To make it work, we could try to not take BQL for all load_cleanup(),
+     * or conditionally unlock BQL only if bql_locked() in VFIO.
+     *
+     * Since most existing call sites take BQL for load_cleanup(), make
+     * it simple by taking BQL always as the rule, so that VFIO can unlock
+     * BQL and retake unconditionally.
      */
-    qemu_loadvm_state_cleanup();
+    assert(bql_locked());
+    qemu_loadvm_state_cleanup(mis);
 
     if (mis->to_src_file) {
         /* Tell source that we are done */
@@ -2891,6 +2904,8 @@ static bool migration_switchover_start(MigrationState *s, Error **errp)
 
     precopy_notify_complete();
 
+    qemu_savevm_maybe_send_switchover_start(s->to_dst_file);
+
     return true;
 }