Re: netfilter: active obj WARN when cleaning up

[Russell King - ARM Linux <linux@arm.linux.org.uk>]

On Wed, Nov 27, 2013 at 02:29:41PM +0100, Thomas Gleixner wrote:
> Though the kobject is the only thing which has a delayed work embedded
> inside struct kmem_cache. And the debug object splat points at the
> kmem_cache_free() of the struct kmem_cache itself. That's why I
> assumed the wreckage around that place. And indeed:
> 
> kmem_cache_destroy(s)
>     __kmem_cache_shutdown(s)
>       sysfs_slab_remove(s)
>         ....
> 	kobject_put(&s->kobj)
>            kref_put(&kobj->kref, kobject_release);
> 	     kobject_release(kref)
>     	       #ifdef CONFIG_DEBUG_KOBJECT_RELEASE
> 	         schedule_delayed_work(&kobj->release)
> 	       #else
> 	        kobject_cleanup(kobj)
> 	       #endif
> 
> So in the CONFIG_DEBUG_KOBJECT_RELEASE=y case, schedule_delayed_work()
> _IS_ called which arms the timer. debugobjects catches the attempt to
> free struct kmem_cache which contains the armed timer.

You fail to show where the free is in the above path.