1 files changed, 4 insertions, 0 deletions
diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c
index ce70adc..6e2d129 100644
--- a/hw/virtio/virtio-balloon.c
+++ b/hw/virtio/virtio-balloon.c
@@ -592,6 +592,8 @@ static void virtio_balloon_free_page_start(VirtIOBalloon *s)
         return;
     }
 
+    qemu_mutex_lock(&s->free_page_lock);
+
     if (s->free_page_report_cmd_id == UINT_MAX) {
         s->free_page_report_cmd_id =
                        VIRTIO_BALLOON_FREE_PAGE_REPORT_CMD_ID_MIN;
@@ -600,6 +602,8 @@ static void virtio_balloon_free_page_start(VirtIOBalloon *s)
     }
 
     s->free_page_report_status = FREE_PAGE_REPORT_S_REQUESTED;
+    qemu_mutex_unlock(&s->free_page_lock);
+
     virtio_notify_config(vdev);
 }