On Fri, 23 Jul 2021 at 18:22, Jason Ekstrand <jason@xxxxxxxxxxxxxx> wrote: > > __i915_ttm_get_pages does two things. First, it calls ttm_bo_validate() > to check the given placement and migrate the BO if needed. Then, it > updates the GEM object to match, in case the object was migrated. If > no migration occured, however, we might still have pages on the GEM > object in which case we don't need to fetch them from TTM and call > __i915_gem_object_set_pages. This hasn't been a problem before because > the primary user of __i915_ttm_get_pages is __i915_gem_object_get_pages > which only calls it if the GEM object doesn't have pages. > > However, i915_ttm_migrate also uses __i915_ttm_get_pages to do the > migration so this meant it was unsafe to call on an already populated > object. This patch checks i915_gem_object_has_pages() before trying to > __i915_gem_object_set_pages so i915_ttm_migrate is safe to call, even on > populated objects. > > Signed-off-by: Jason Ekstrand <jason@xxxxxxxxxxxxxx> Reviewed-by: Matthew Auld <matthew.auld@xxxxxxxxx>
