From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43)
	id 1Lu50G-0005jg-2V
	for qemu-devel@nongnu.org; Wed, 15 Apr 2009 09:18:12 -0400
Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43)
	id 1Lu50B-0005h6-Bb
	for qemu-devel@nongnu.org; Wed, 15 Apr 2009 09:18:11 -0400
Received: from [199.232.76.173] (port=44434 helo=monty-python.gnu.org)
	by lists.gnu.org with esmtp (Exim 4.43) id 1Lu50B-0005h2-57
	for qemu-devel@nongnu.org; Wed, 15 Apr 2009 09:18:07 -0400
Received: from mx2.redhat.com ([66.187.237.31]:56872)
	by monty-python.gnu.org with esmtp (Exim 4.60)
	(envelope-from <markmc@redhat.com>) id 1Lu50A-0007eB-Nj
	for qemu-devel@nongnu.org; Wed, 15 Apr 2009 09:18:07 -0400
Received: from int-mx2.corp.redhat.com (int-mx2.corp.redhat.com [172.16.27.26])
	by mx2.redhat.com (8.13.8/8.13.8) with ESMTP id n3FDI6Xh029356
	for <qemu-devel@nongnu.org>; Wed, 15 Apr 2009 09:18:06 -0400
Received: from ns3.rdu.redhat.com (ns3.rdu.redhat.com [10.11.255.199])
	by int-mx2.corp.redhat.com (8.13.1/8.13.1) with ESMTP id n3FDI5ME005648
	for <qemu-devel@nongnu.org>; Wed, 15 Apr 2009 09:18:05 -0400
Received: from [127.0.0.1] (file.rdu.redhat.com [10.11.255.147])
	by ns3.rdu.redhat.com (8.13.8/8.13.8) with ESMTP id n3FDI4pw008227
	for <qemu-devel@nongnu.org>; Wed, 15 Apr 2009 09:18:04 -0400
Subject: Re: [Qemu-devel] [PATCH 4/7] net: Prevent multiple slirp instances
From: Mark McLoughlin <markmc@redhat.com>
In-Reply-To: <20090414172954.15035.41102.stgit@mchn012c.ww002.siemens.net>
References: <20090414172954.15035.73053.stgit@mchn012c.ww002.siemens.net>
	<20090414172954.15035.41102.stgit@mchn012c.ww002.siemens.net>
Content-Type: text/plain
Date: Wed, 15 Apr 2009 14:09:52 +0100
Message-Id: <1239800992.4431.130.camel@blaa>
Mime-Version: 1.0
Content-Transfer-Encoding: 7bit
Reply-To: Mark McLoughlin <markmc@redhat.com>, qemu-devel@nongnu.org
List-Id: qemu-devel.nongnu.org
List-Unsubscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.gnu.org/pipermail/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: qemu-devel@nongnu.org

On Tue, 2009-04-14 at 19:29 +0200, Jan Kiszka wrote:
> The slirp stack is full of global variables which prevents instantiating
> it more than once. Catch this during net_slirp_init to prevent more harm
> later on.
> 
> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
> ---
> 
>  net.c |   14 +++++++++++++-
>  1 files changed, 13 insertions(+), 1 deletions(-)
> 
> diff --git a/net.c b/net.c
> index 787f249..0486f7c 100644
> --- a/net.c
> +++ b/net.c
> @@ -519,15 +519,27 @@ static void slirp_receive(void *opaque, const uint8_t *buf, int size)
>      slirp_input(buf, size);
>  }
>  
> +static int slirp_in_use;
> +
> +static void net_slirp_cleanup(void *opaque)
> +{
> +    slirp_in_use = 0;
> +}
> +
>  static int net_slirp_init(VLANState *vlan, const char *model, const char *name)
>  {
> +    if (slirp_in_use) {
> +        /* slirp only supports a single instance so far */
> +        return -1;
> +    }
>      if (!slirp_inited) {
>          slirp_inited = 1;
>          slirp_init(slirp_restrict, slirp_ip);
>      }
>      slirp_vc = qemu_new_vlan_client(vlan, model, name,
> -                                    slirp_receive, NULL, NULL, NULL);
> +                                    slirp_receive, NULL, net_slirp_cleanup, NULL);
>      slirp_vc->info_str[0] = '\0';
> +    slirp_in_use = 1;
>      return 0;

Yeah, it's ugly but probably the best we can do right now.

Acked-by: Mark McLoughlin <markmc@redhat.com>

Cheers,
Mark.