diff --git a/src/gallium/drivers/nv50/nv50_screen.c b/src/gallium/drivers/nv50/nv50_screen.c
index 235cd82..d9da510 100644
--- a/src/gallium/drivers/nv50/nv50_screen.c
+++ b/src/gallium/drivers/nv50/nv50_screen.c
@@ -453,6 +453,14 @@ nv50_screen_create(struct pipe_winsys *ws, struct nouveau_device *dev)
    if (ret)
       goto fail;

+   ret = nouveau_bo_map(screen->code, NOUVEAU_BO_RDWR);
+   if (ret)
+      goto fail;
+
+   void* map = screen->code->map;
+   memset(map, 0xa4, 3 << NV50_CODE_BO_SIZE_LOG2);
+   nouveau_bo_unmap(screen->code);
+
    nouveau_resource_init(&screen->vp_code_heap, 0, 1 << NV50_CODE_BO_SIZE_LOG2);
    nouveau_resource_init(&screen->gp_code_heap, 0, 1 << NV50_CODE_BO_SIZE_LOG2);
    nouveau_resource_init(&screen->fp_code_heap, 0, 1 << NV50_CODE_BO_SIZE_LOG2);