From: Pablo Neira Ayuso <pablo@netfilter.org>
To: Hans Schillstrom <hans.schillstrom@ericsson.com>
Cc: "netfilter-devel@vger.kernel.org" <netfilter-devel@vger.kernel.org>
Subject: Re: conntrack, suspicious RCU usage
Date: Thu, 12 Jan 2012 03:30:44 +0100 [thread overview]
Message-ID: <20120112023044.GB12255@1984> (raw)
In-Reply-To: <201201111025.50994.hans.schillstrom@ericsson.com>
On Wed, Jan 11, 2012 at 10:25:50AM +0100, Hans Schillstrom wrote:
> Hello
> I got this the first time using conntrack -L when there is a lot of traffic.
> It doesn't result in any thing bad yet.
>
> Is this a know thing ?
No, you have been the first to spot this.
> or should I dig into it..
>
> I'm running the latest and greatest conntrack / netfilter tools and libs.
>
> ===============================
> [ INFO: suspicious RCU usage. ]
> -------------------------------
> /home/hans/evip.git/kvm/net-next.git/include/net/netfilter/nf_conntrack_l3proto.h:92 suspicious rcu_dereference_check() usage!
We were using rcu in the table dumping time ago, but we had to replace
rcu by spinlocks.
ctnetlink_dump_tuples is used in both RCU context and spinlock
context, this seems to be the problem.
it seems I didn't enable RCU read lock verification in my kernels.
I'll do it to catch up this sort of problems.
thanks for the report.
prev parent reply other threads:[~2012-01-12 2:30 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-01-11 9:25 conntrack, suspicious RCU usage Hans Schillstrom
2012-01-11 10:01 ` Eric Dumazet
2012-01-11 13:24 ` Hans Schillstrom
2012-01-11 13:33 ` Eric Dumazet
2012-01-11 13:44 ` Hans Schillstrom
2012-01-11 14:56 ` Eric Dumazet
2012-01-12 2:35 ` Pablo Neira Ayuso
2012-01-12 8:15 ` Hans Schillstrom
2012-01-12 2:30 ` Pablo Neira Ayuso [this message]
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