diff --git a/src/gallium/drivers/zink/zink_surface.c b/src/gallium/drivers/zink/zink_surface.c
index e9c02af0c92..d5d0a3c6dbc 100644
--- a/src/gallium/drivers/zink/zink_surface.c
+++ b/src/gallium/drivers/zink/zink_surface.c
@@ -94,6 +94,7 @@ zink_create_surface(struct pipe_context *pctx,
    }
 
    ivci.format = zink_get_format(screen, templ->format);
+   assert(ivci.format != VK_FORMAT_UNDEFINED);
 
    // TODO: format swizzles
    ivci.components.r = VK_COMPONENT_SWIZZLE_R;