From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-bk0-f50.google.com (mail-bk0-f50.google.com [209.85.214.50]) by kanga.kvack.org (Postfix) with ESMTP id 115A96B0031 for ; Wed, 27 Nov 2013 05:45:30 -0500 (EST) Received: by mail-bk0-f50.google.com with SMTP id e11so3057249bkh.23 for ; Wed, 27 Nov 2013 02:45:30 -0800 (PST) Received: from Galois.linutronix.de (Galois.linutronix.de. [2001:470:1f0b:db:abcd:42:0:1]) by mx.google.com with ESMTPS id rl9si12089414bkb.67.2013.11.27.02.45.29 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Wed, 27 Nov 2013 02:45:30 -0800 (PST) Date: Wed, 27 Nov 2013 11:45:17 +0100 (CET) From: Thomas Gleixner Subject: Re: netfilter: active obj WARN when cleaning up In-Reply-To: <20131126230709.GA10948@localhost> Message-ID: References: <522B25B5.6000808@oracle.com> <5294F27D.4000108@oracle.com> <20131126230709.GA10948@localhost> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Pablo Neira Ayuso Cc: Sasha Levin , Patrick McHardy , kadlec@blackhole.kfki.hu, "David S. Miller" , netfilter-devel@vger.kernel.org, coreteam@netfilter.org, netdev@vger.kernel.org, LKML , linux-mm@kvack.org, Andrew Morton , Christoph Lameter , Greg KH , Russell King On Wed, 27 Nov 2013, Pablo Neira Ayuso wrote: > On Tue, Nov 26, 2013 at 02:11:57PM -0500, Sasha Levin wrote: > > Ping? I still see this warning. > > Did your test include patch 0c3c6c00c6? And how is that patch supposed to help? > > >[ 418.312449] WARNING: CPU: 6 PID: 4178 at lib/debugobjects.c:260 debug_print_object+0x8d/0xb0() > > >[ 418.313243] ODEBUG: free active (active state 0) object type: timer_list hint: > > >delayed_work_timer_fn+0x0/0x20 > > >[ 418.321101] [] kmem_cache_free+0x197/0x340 > > >[ 418.321101] [] kmem_cache_destroy+0x86/0xe0 > > >[ 418.321101] [] nf_conntrack_cleanup_net_list+0x131/0x170 The debug code detects an active timer, which itself is part of a delayed work struct. The call comes from kmem_cache_destroy(). kmem_cache_free(kmem_cache, s); So debug object says: s contains an active timer. s is the kmem_cache which is destroyed from nf_conntrack_cleanup_net_list. Now struct kmem_cache has in case of SLUB: struct kobject kobj; /* For sysfs */ and struct kobject has: #ifdef CONFIG_DEBUG_KOBJECT_RELEASE struct delayed_work release; #endif So this is the thing you want to look at: commit c817a67ec (kobject: delayed kobject release: help find buggy drivers) added that delayed work thing. I fear that does not work for kobjects which are embedded into something else. Handing off to rmk, mm and kobject folks. Thanks, tglx -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org