diff --git a/src/gallium/drivers/iris/iris_batch.c b/src/gallium/drivers/iris/iris_batch.c
index cf388afd1c2..c3378a29e5a 100644
--- a/src/gallium/drivers/iris/iris_batch.c
+++ b/src/gallium/drivers/iris/iris_batch.c
@@ -744,6 +744,8 @@ update_bo_syncobjs(struct iris_batch *batch, struct iris_bo *bo, bool write)
    struct iris_bufmgr *bufmgr = screen->bufmgr;
    struct iris_context *ice = batch->ice;
 
+   simple_mtx_assert_locked(iris_bufmgr_get_bo_deps_lock(bufmgr));
+
    /* Make sure bo->deps is big enough */
    if (screen->id >= bo->deps_size) {
       int new_size = screen->id + 1;