postcopy: listen thread is never joined

We don't join the listen thread, it does its own cleanup.
Mark as detached not joinable.
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reported-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1457690016-9070-2-git-send-email-dgilbert@redhat.com>
Signed-off-by: NAmit Shah <amit.shah@redhat.com>

migration/savevm.c

@@ -1494,7 +1494,7 @@ static int loadvm_postcopy_handle_listen(MigrationIncomingState *mis)
     qemu_sem_init(&mis->listen_thread_sem, 0);
     qemu_thread_create(&mis->listen_thread, "postcopy/listen",
                        postcopy_ram_listen_thread, mis->from_src_file,
-                       QEMU_THREAD_JOINABLE);
+                       QEMU_THREAD_DETACHED);
     qemu_sem_wait(&mis->listen_thread_sem);
     qemu_sem_destroy(&mis->listen_thread_sem);