svga_context_flush(svga, &fence);
screen->fence_finish(screen, NULL, fence, PIPE_TIMEOUT_INFINITE);
screen->fence_reference(screen, &fence, NULL);
svga_context_flush(svga, &fence);
screen->fence_finish(screen, NULL, fence, PIPE_TIMEOUT_INFINITE);
screen->fence_reference(screen, &fence, NULL);