| Message ID | 1371352470-3226-1-git-send-email-gaofeng@cn.fujitsu.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
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. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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. > > > Hi, 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? Thanks -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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? It is designed this way. Greetings, Hannes -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 2014/1/2 14:03, 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? > > It is designed this way. > > Greetings, > > Hannes > > > . > Can you give more explanation about this please? Thanks! -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, Jan 02, 2014 at 04:13:40PM +0800, chenweilong wrote:
> Can you give more explanation about this please?
If you look at the routing table for local addresses (ip -6 route list table
local), you see that every address which is RTF_LOCAL (and thus passes up the
packets via ip6_input) has as its device the loopback device.
In case you shutdown loopback you clear all those routes, thus incoming
packets won't find the corresponding rt6_info which directs the packets to
passed up the stack.
I guess it was done to satisfy the scoped architecture of IPv6.
Does this help you?
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On 2014/1/2 16:32, Hannes Frederic Sowa wrote: > On Thu, Jan 02, 2014 at 04:13:40PM +0800, chenweilong wrote: >> Can you give more explanation about this please? > > If you look at the routing table for local addresses (ip -6 route list table > local), you see that every address which is RTF_LOCAL (and thus passes up the > packets via ip6_input) has as its device the loopback device. > > In case you shutdown loopback you clear all those routes, thus incoming > packets won't find the corresponding rt6_info which directs the packets to > passed up the stack. > > I guess it was done to satisfy the scoped architecture of IPv6. > > Does this help you? > > > Yes,thanks very much! -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 1bbf744..77b6261 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -2655,6 +2655,9 @@ static void init_loopback(struct net_device *dev) if (sp_ifa->flags & (IFA_F_DADFAILED | IFA_F_TENTATIVE)) continue; + if (sp_ifa->rt) + continue; + sp_rt = addrconf_dst_alloc(idev, &sp_ifa->addr, 0); /* Failure cases are ignored */
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> --- net/ipv6/addrconf.c | 3 +++ 1 file changed, 3 insertions(+)