Test struct drm_gem_object.import_attach to detect imported objects during cleanup. At that point, the imported DMA buffer might have already been released and the dma_buf field is NULL. The object's free callback then does a cleanup as for native objects.
Happens for calls to drm_mode_destroy_dumb_ioctl() that eventually clear the dma_buf field in drm_gem_object_exported_dma_buf_free(). Signed-off-by: Thomas Zimmermann <tzimmerm...@suse.de> Fixes: b57aa47d39e9 ("drm/gem: Test for imported GEM buffers with helper") Reported-by: Andy Yan <andys...@163.com> Closes: https://lore.kernel.org/dri-devel/38d09d34.4354.196379aa560.coremail.andys...@163.com/ Tested-by: Andy Yan <andys...@163.com> Cc: Thomas Zimmermann <tzimmerm...@suse.de> Cc: Anusha Srivatsa <asriv...@redhat.com> Cc: Christian König <christian.koe...@amd.com> Cc: Maarten Lankhorst <maarten.lankho...@linux.intel.com> Cc: Maxime Ripard <mrip...@kernel.org> Cc: David Airlie <airl...@gmail.com> Cc: Simona Vetter <sim...@ffwll.ch> Cc: Sumit Semwal <sumit.sem...@linaro.org> Cc: "Christian König" <christian.koe...@amd.com> Cc: dri-devel@lists.freedesktop.org Cc: linux-me...@vger.kernel.org Cc: linaro-mm-...@lists.linaro.org --- include/drm/drm_gem.h | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h index 9b71f7a9f3f8..f09b8afcf86d 100644 --- a/include/drm/drm_gem.h +++ b/include/drm/drm_gem.h @@ -589,7 +589,13 @@ static inline bool drm_gem_object_is_shared_for_memory_stats(struct drm_gem_obje static inline bool drm_gem_is_imported(const struct drm_gem_object *obj) { /* The dma-buf's priv field points to the original GEM object. */ - return obj->dma_buf && (obj->dma_buf->priv != obj); + return (obj->dma_buf && (obj->dma_buf->priv != obj)) || + /* + * TODO: During object release, the dma-buf might already + * be gone. For now keep testing import_attach, but + * this should be removed at some point. + */ + obj->import_attach; } #ifdef CONFIG_LOCKDEP -- 2.49.0