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Date: Mon, 1 Jul 2013 13:50:57 +0200
From: Stefan Hajnoczi <stefanha@gmail.com>
Message-ID: <20130701115057.GC5543@stefanha-thinkpad.redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v2 3/6] net: make netclient re-entrant with
 refcnt
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To: liu ping fan <qemulist@gmail.com>
Cc: qemu-devel@nongnu.org, Stefan Hajnoczi <stefanha@redhat.com>, mdroth <mdroth@linux.vnet.ibm.com>

On Thu, Jun 20, 2013 at 05:14:56PM +0800, liu ping fan wrote:
> On Tue, Jun 18, 2013 at 8:41 PM, Stefan Hajnoczi <stefanha@gmail.com> wrote:
> > On Thu, Jun 13, 2013 at 05:03:03PM +0800, Liu Ping Fan wrote:
> >> @@ -1109,6 +1146,7 @@ void net_cleanup(void)
> >>              qemu_del_net_client(nc);
> >>          }
> >>      }
> >> +    qemu_mutex_destroy(&net_clients_lock);
> >
> > Why is it okay to iterate over net_clients here without the lock?
> 
>  atexit(&net_cleanup); So no other racers exist.

What about dataplane?  The device may not be reset when net_cleanup runs.

It's best not to make assumptions, taking the lock is easy.

Stefan