From: chenweilong <chenweilong@huawei•com>
To: David Miller <davem@davemloft•net>, <gaofeng@cn•fujitsu.com>,
<kumaran.4353@gmail•com>, <netdev@vger•kernel.org>,
Hannes Frederic Sowa <hannes@stressinduktion•org>
Subject: Re: [PATCH] ipv6: don't call addrconf_dst_alloc again when enable lo
Date: Thu, 2 Jan 2014 15:58:22 +0800 [thread overview]
Message-ID: <52C51C1E.9040603@huawei.com> (raw)
In-Reply-To: <20140102065429.GB22494@order.stressinduktion.org>
On 2014/1/2 14:54, Hannes Frederic Sowa wrote:
> On Thu, Jan 02, 2014 at 01:48:46PM +0800, chenweilong wrote:
>> On 2013/12/31 11:57, Hannes Frederic Sowa wrote:
>>> On Wed, Jun 19, 2013 at 11:05:32PM -0700, David Miller wrote:
>>>> From: Gao feng <gaofeng@cn•fujitsu.com>
>>>> Date: Sun, 16 Jun 2013 11:14:30 +0800
>>>>
>>>>> If we disable all of the net interfaces, and enable
>>>>> un-lo interface before lo interface, we already allocated
>>>>> the addrconf dst in ipv6_add_addr. So we shouldn't allocate
>>>>> it again when we enable lo interface.
>>>>>
>>>>> Otherwise the message below will be triggered.
>>>>> unregister_netdevice: waiting for sit1 to become free. Usage count = 1
>>>>>
>>>>> This problem is introduced by commit 25fb6ca4ed9cad72f14f61629b68dc03c0d9713f
>>>>> "net IPv6 : Fix broken IPv6 routing table after loopback down-up"
>>>>>
>>>>> Signed-off-by: Gao feng <gaofeng@cn•fujitsu.com>
>>>>
>>>> This is the second such regression added by that commit :-/
>>>>
>>>> Applied and queue up for -stable, thanks.
>>>
>>> Hmm, and this change also has a regression and breaks the original fix. :/
>>>
>>> https://bugzilla.kernel.org/show_bug.cgi?id=67951
>>>
>>> I tried to track it down but it seems pretty complicated. Maybe we have to
>>> special-case the take-down of the loopback device.
>>>
>>>
>>>
>>
>> When I did the tests,If 'ifconfig lo down',all IPv6 connection broken,
>> but IPv4 connection were still OK.
>>
>> Is it designed like that or a bug?
>
> This seems to solve the loopback up/down problem, but there are still
> some issues with up/down of interfaces and routing table interactions.
>
> We enable routes over interfaces when interface is actually down and
> kick manually specified on-link routes when we actually should try to
> keep them and just disable them.
>
> diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
> index 6c16345..61d752a 100644
> --- a/net/ipv6/addrconf.c
> +++ b/net/ipv6/addrconf.c
> @@ -2629,8 +2629,10 @@ static void init_loopback(struct net_device *dev)
> if (sp_ifa->flags & (IFA_F_DADFAILED | IFA_F_TENTATIVE))
> continue;
>
> - if (sp_ifa->rt)
> + if (sp_ifa->rt) {
> + ip6_ins_rt(sp_ifa->rt);
> continue;
> + }
>
> sp_rt = addrconf_dst_alloc(idev, &sp_ifa->addr, false);
>
>
> .
>
I test the patch,it has the problem Gao feng reported.
How about this:
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index d5fa5b8..5e2db6e 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -2609,10 +2609,13 @@ static void init_loopback(struct net_device *dev)
if (sp_ifa->flags & (IFA_F_DADFAILED | IFA_F_TENTATIVE))
continue;
- if (sp_ifa->rt)
- continue;
+ if (sp_ifa->rt && sp_ifa->rt->dst.dev == dev){
+ ip6_del_rt(sp_ifa->rt);
+ }
sp_rt = addrconf_dst_alloc(idev, &sp_ifa->addr, false);
/* Failure cases are ignored */
next prev parent reply other threads:[~2014-01-02 7:58 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-06-16 3:14 [PATCH] ipv6: don't call addrconf_dst_alloc again when enable lo Gao feng
2013-06-20 6:05 ` David Miller
2013-12-31 3:57 ` Hannes Frederic Sowa
2014-01-02 5:48 ` chenweilong
2014-01-02 6:03 ` Hannes Frederic Sowa
2014-01-02 8:13 ` chenweilong
2014-01-02 8:32 ` Hannes Frederic Sowa
2014-01-02 9:08 ` chenweilong
2014-01-02 6:54 ` Hannes Frederic Sowa
2014-01-02 7:58 ` chenweilong [this message]
2014-01-02 8:23 ` Hannes Frederic Sowa
2014-01-02 9:33 ` chenweilong
2014-01-03 6:53 ` Hannes Frederic Sowa
2014-01-08 7:50 ` Gao feng
2014-01-08 8:05 ` Hannes Frederic Sowa
2014-01-08 8:42 ` Gao feng
2014-01-08 8:55 ` Hannes Frederic Sowa
2014-01-17 2:02 ` chenweilong
2014-01-17 4:09 ` Hannes Frederic Sowa
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