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Subject: Re: unregister_netdevice: waiting for DEV to become free (2)
To:     Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>,
        David Ahern <dsahern@gmail.com>,
        "David S. Miller" <davem@davemloft.net>
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        syzkaller-bugs@googlegroups.com
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From:   Eric Dumazet <eric.dumazet@gmail.com>
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Date:   Sat, 27 Apr 2019 16:52:31 -0700
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On 4/27/19 3:33 PM, Tetsuo Handa wrote:
> 
> I'm waiting for davem why it is safe to move the dst entry from
> "a device to unregister" to "a loopback device in that namespace".
> I'm waiting for an explanation how the dst entry which was moved to
> "a loopback device in that namespace" is released (i.e. what the
> expected shutdown sequence is).

The most probable explanation is that we make sure the loopback device
is the last one to be dismantled at netns deletion,
and this would obviously happen after all dst have been released.