Re: [PATCH] accel/ivpu: Improve BO alloc/free warnings

[Karol Wachowski <karol.wachowski@linux.intel.com>]

Reviewed-by: Karol Wachowski <karol.wachowski@linux.intel.com>

On 9/25/2025 4:51 PM, Maciej Falkowski wrote:
> From: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
>
> Add additional warnings related to allocation and
> deallocation of buffer objects to better track possible
> memory leaks and generally the BO's lifecycle.
>
> Introduce checks for handle_count to ensure it is zero
> before creating a new handle, and exactly one
> after successfully creating a handle.
>
> Introduce also a check to warn if the VMA node is not
> empty when freeing the buffer object.
>
> Signed-off-by: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
> Signed-off-by: Maciej Falkowski <maciej.falkowski@linux.intel.com>
> ---
>  drivers/accel/ivpu/ivpu_gem.c | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/accel/ivpu/ivpu_gem.c b/drivers/accel/ivpu/ivpu_gem.c
> index 38ecf933d144..e9830ad48d4b 100644
> --- a/drivers/accel/ivpu/ivpu_gem.c
> +++ b/drivers/accel/ivpu/ivpu_gem.c
> @@ -332,6 +332,7 @@ static void ivpu_gem_bo_free(struct drm_gem_object *obj)
>  	drm_WARN_ON(&vdev->drm, bo->ctx);
>  
>  	drm_WARN_ON(obj->dev, refcount_read(&bo->base.pages_use_count) > 1);
> +	drm_WARN_ON(obj->dev, bo->base.base.vma_node.vm_files.rb_node);
>  	drm_gem_shmem_free(&bo->base);
>  }
>  
> @@ -370,12 +371,16 @@ int ivpu_bo_create_ioctl(struct drm_device *dev, void *data, struct drm_file *fi
>  		return PTR_ERR(bo);
>  	}
>  
> +	drm_WARN_ON(&vdev->drm, bo->base.base.handle_count != 0);
> +
>  	ret = drm_gem_handle_create(file, &bo->base.base, &args->handle);
> -	if (ret)
> +	if (ret) {
>  		ivpu_err(vdev, "Failed to create handle for BO: %pe (ctx %u size %llu flags 0x%x)",
>  			 bo, file_priv->ctx.id, args->size, args->flags);
> -	else
> +	} else {
>  		args->vpu_addr = bo->vpu_addr;
> +		drm_WARN_ON(&vdev->drm, bo->base.base.handle_count != 1);
> +	}
>  
>  	drm_gem_object_put(&bo->base.base);
>