From: Thierry Reding treding@nvidia.com
When the last reference to a TTM BO is dropped, ttm_bo_release() will acquire the DMA reservation object's wound/wait mutex while trying to clean up (ttm_bo_cleanup_refs_or_queue() via ttm_bo_release()). It is therefore essential that drm_gem_object_release() be called after the TTM BO has been uninitialized, otherwise drm_gem_object_release() has already destroyed the wound/wait mutex (via dma_resv_fini()).
Signed-off-by: Thierry Reding treding@nvidia.com --- drivers/gpu/drm/nouveau/nouveau_bo.c | 10 ++++++++-- drivers/gpu/drm/nouveau/nouveau_gem.c | 4 ---- 2 files changed, 8 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/nouveau/nouveau_bo.c b/drivers/gpu/drm/nouveau/nouveau_bo.c index e7803dca32c5..f8015e0318d7 100644 --- a/drivers/gpu/drm/nouveau/nouveau_bo.c +++ b/drivers/gpu/drm/nouveau/nouveau_bo.c @@ -136,10 +136,16 @@ nouveau_bo_del_ttm(struct ttm_buffer_object *bo) struct drm_device *dev = drm->dev; struct nouveau_bo *nvbo = nouveau_bo(bo);
- if (unlikely(nvbo->bo.base.filp)) - DRM_ERROR("bo %p still attached to GEM object\n", bo); WARN_ON(nvbo->pin_refcnt > 0); nv10_bo_put_tile_region(dev, nvbo->tile, NULL); + + /* + * If nouveau_bo_new() allocated this buffer, the GEM object was never + * initialized, so don't attempt to release it. + */ + if (bo->base.dev) + drm_gem_object_release(&bo->base); + kfree(nvbo); }
diff --git a/drivers/gpu/drm/nouveau/nouveau_gem.c b/drivers/gpu/drm/nouveau/nouveau_gem.c index 1bdffd714456..1324c19f4e5c 100644 --- a/drivers/gpu/drm/nouveau/nouveau_gem.c +++ b/drivers/gpu/drm/nouveau/nouveau_gem.c @@ -51,10 +51,6 @@ nouveau_gem_object_del(struct drm_gem_object *gem) if (gem->import_attach) drm_prime_gem_destroy(gem, nvbo->bo.sg);
- drm_gem_object_release(gem); - - /* reset filp so nouveau_bo_del_ttm() can test for it */ - gem->filp = NULL; ttm_bo_put(&nvbo->bo);
pm_runtime_mark_last_busy(dev);