Re: [PATCH v4 3/4] drm/vmwgfx: Fix handling of dumb buffers

On Thu, Jul 18, 2024 at 11:22 AM Zack Rusin zack.rusin@broadcom.com wrote:

+bool vmw_user_object_is_mapped(struct vmw_user_object *uo) +{

•   struct vmw_bo *bo;
  

•   if (!uo || vmw_user_object_is_null(uo))
  

•           return false;
  

•   bo = vmw_user_object_buffer(uo);
  

•   WARN_ON(!bo);
  

•   return (bo && bo->map.bo);
  

+}

map.bo is set in ttm_bo_kmap but is not reset to NULL in ttm_bo_kunmap. We only reset it in our vmw_bo_unmap. So we have to ensure all unmaps go through our vmw_bo_unmap or use map.virtual instead of map.bo to indicate the presence of a mapping. I prefer the latter.