From: Cong Wang <xiyou.wangcong@gmail.com>
To: Matt Bennett <Matt.Bennett@alliedtelesis.co.nz>
Cc: "linux-ppp@vger.kernel.org" <linux-ppp@vger.kernel.org>,
"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
"g.nault@alphalink.fr" <g.nault@alphalink.fr>
Subject: Re: Problem: BUG_ON hit in ppp_pernet() when re-connect after changing shared key on LAC
Date: Tue, 5 Jul 2016 10:59:55 -0700 [thread overview]
Message-ID: <CAM_iQpVyNghNJHES5-npZgYGFXps0-XTwJyJ-9pLDAuYJ_syWw@mail.gmail.com> (raw)
In-Reply-To: <7fabf4defe2f468bbcc829247de956c0@svr-chch-ex1.atlnz.lc>
On Mon, Jul 4, 2016 at 7:50 PM, Matt Bennett
<Matt.Bennett@alliedtelesis.co.nz> wrote:
> Using printk I have confirmed that ppp_pernet() is called from
> ppp_connect_channel() when the BUG occurs (i.e. pch->chan_net is NULL).
>
> This behavior appears to have been introduced in commit 1f461dc ("ppp:
> take reference on channels netns").
We have some race condition here, where a parallel ppp_unregister_channel()
could happen while we are in ppp_connect_channel().
We need some synchronization for them. I am not sure what is the right lock
here since ppp locking looks crazy.
next prev parent reply other threads:[~2016-07-05 18:00 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-07-05 2:50 Problem: BUG_ON hit in ppp_pernet() when re-connect after changing shared key on LAC Matt Bennett
2016-07-05 17:59 ` Cong Wang [this message]
2016-07-05 20:36 ` Cong Wang
2016-07-06 0:05 ` Matt Bennett
2016-07-06 2:02 ` Cong Wang
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