From: Eric Dumazet <eric.dumazet@gmail.com>
To: Vladimir Davydov <vdavydov@parallels.com>
Cc: netdev@vger.kernel.org
Subject: Re: Possible deadlock in ipv6?
Date: Wed, 06 Jun 2012 17:53:39 +0200 [thread overview]
Message-ID: <1338998019.26966.10.camel@edumazet-glaptop> (raw)
In-Reply-To: <4FCF6DF4.2090304@parallels.com>
On Wed, 2012-06-06 at 18:49 +0400, Vladimir Davydov wrote:
> I'm not familiar with the linux net subsystem, so I would appreciate if
> someone could clarify if the following call chain is possible:
>
> addrconf_ifdown() calls neigh_ifdown(nd_tbl) which locks nd_tbl.lock for
> writing and calls
>
> pneigh_ifdown
> pndisc_destructor
> ipv6_dev_mc_dec
> __ipv6_dev_mc_dec
> igmp6_group_dropped
> igmp6_leave_group
> igmp6_send
> icmp6_dst_alloc
> ip6_neigh_lookup
> neigh_create
>
> and neigh_create() locks nd_tbl.lock for writing again resulting in a
> deadlock.
It seems a deadlock is possible indeed, good catch !
next prev parent reply other threads:[~2012-06-06 15:53 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-06-06 14:49 Possible deadlock in ipv6? Vladimir Davydov
2012-06-06 15:53 ` Eric Dumazet [this message]
2012-06-06 15:58 ` Eric Dumazet
2012-06-06 16:01 ` Vladimir Davydov
2012-06-06 17:02 ` Eric Dumazet
2012-06-12 6:54 ` David Miller
2012-06-12 9:09 ` Eric Dumazet
2012-06-21 4:05 ` David Miller
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