From: "Justin P. Mattock" <justinmattock@gmail.com>
To: Dave Jones <davej@redhat.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
netdev <netdev@vger.kernel.org>
Subject: Re: INFO: suspicious rcu_dereference_check() usage.
Date: Tue, 24 May 2011 09:22:37 -0700 [thread overview]
Message-ID: <4DDBDB4D.4080606@gmail.com> (raw)
In-Reply-To: <20110524155608.GA17977@redhat.com>
On 05/24/2011 08:56 AM, Dave Jones wrote:
> On Mon, May 23, 2011 at 11:50:46PM -0700, Justin Mattock wrote:
>
> > [ 2862.310349] WARNING: at net/ipv4/route.c:1668 ip_rt_bug+0x5c/0x62()
>
> Awesome, adding that WARN_ON paid off. This is the same bug I've been trying
> to reproduce the last few weeks. DaveM mentioned that it means we used
> an input route for packet output.
>
> > [ 2862.310414] Pid: 6153, comm: gcm-session Not tainted
> > 2.6.39-04906-g5e152b4-dirty #2
> > [ 2862.310417] Call Trace:
> > [ 2862.310424] [<ffffffff8104c634>] warn_slowpath_common+0x83/0x9b
> > [ 2862.310430] [<ffffffff8104c666>] warn_slowpath_null+0x1a/0x1c
> > [ 2862.310434] [<ffffffff814095c9>] ip_rt_bug+0x5c/0x62
> > [ 2862.310439] [<ffffffff814112a1>] dst_output+0x19/0x1d
> > [ 2862.310443] [<ffffffff81412aa0>] ip_local_out+0x20/0x25
> > [ 2862.310448] [<ffffffff814139c9>] ip_send_skb+0x19/0x58
> > [ 2862.310453] [<ffffffff8142fa4e>] udp_send_skb+0x239/0x29b
> > [ 2862.310458] [<ffffffff814310f0>] udp_sendmsg+0x5a1/0x7d4
> > [ 2862.310464] [<ffffffff81079408>] ? trace_hardirqs_off+0xd/0xf
> > [ 2862.310469] [<ffffffff8141139c>] ? ip_select_ident+0x3d/0x3d
> > [ 2862.310475] [<ffffffff810525b8>] ? local_bh_enable_ip+0xe/0x10
> > [ 2862.310481] [<ffffffff8148f131>] ? _raw_spin_unlock_bh+0x31/0x35
> > [ 2862.310486] [<ffffffff813d41a6>] ? release_sock+0x14c/0x155
> > [ 2862.310490] [<ffffffff814386ac>] inet_sendmsg+0x66/0x6f
> > [ 2862.310495] [<ffffffff813d02b0>] sock_sendmsg+0xe6/0x109
> > [ 2862.310501] [<ffffffff8107d63f>] ? lock_acquire+0xe1/0x109
> > [ 2862.310505] [<ffffffff8107d535>] ? lock_release+0x1aa/0x1d3
> > [ 2862.310512] [<ffffffff810ed549>] ? might_fault+0xa5/0xac
> > [ 2862.310516] [<ffffffff813ceb34>] ? copy_from_user+0x2f/0x31
> > [ 2862.310521] [<ffffffff813d1f34>] sys_sendto+0x132/0x174
> > [ 2862.310526] [<ffffffff81495cfa>] ? sysret_check+0x2e/0x69
> > [ 2862.310531] [<ffffffff8107b016>] ? trace_hardirqs_on_caller+0x13f/0x172
> > [ 2862.310537] [<ffffffff8109fd4d>] ? audit_syscall_entry+0x11c/0x148
> > [ 2862.310542] [<ffffffff8121debe>] ? trace_hardirqs_on_thunk+0x3a/0x3f
> > [ 2862.310546] [<ffffffff81495cc2>] system_call_fastpath+0x16/0x1b
> > [ 2862.310549] ---[ end trace 2d2332adaa8bf2b5 ]---
> > [ 2863.373889] ip_rt_bug: 10.0.0.10 -> 255.255.255.255, ?
>
> The common thing between your bug and the trace I triggered was the
> destination ip reported. A clue maybe ?
>
> Dave
>
>
there was a bug for http://marc.info/?l=linux-kernel&m=129913127722786&w=2
but looking I see something in there with recv.c not route.c but
probably something
same or in the same vacinity. as for the sluggishness I have been
noticing the system doing so, but
never saw anything like the above, so if it is your WARN_ON then kudos
to you!
Justin P. Mattock
next prev parent reply other threads:[~2011-05-24 16:22 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <4DDB491A.2070901@gmail.com>
2011-05-24 6:50 ` INFO: suspicious rcu_dereference_check() usage Justin Mattock
2011-05-24 15:56 ` Dave Jones
2011-05-24 16:22 ` Justin P. Mattock [this message]
2011-06-09 4:49 ` Justin Mattock
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