Re: [libvirt] LXC: autostart feature does set all interfaces to state up.

On 07/10/2013 03:23 PM, Richard Weinberger wrote: > Am 10.07.2013 09:03, schrieb Gao feng: >> On 07/10/2013 02:00 PM, Richard Weinberger wrote: >> >>>> >>>> Yes,actually libvirt did up the veth devices, that's why only veth2& veth5 are down. >>> >>> Where does libvirt up the devices? The debug log does not contain any "ip link set dev XXX up" commands. >>> Also in src/util/virnetdevveth.c I'm unable to find such a ip command. >>> >> >> virLXCProcessSetupInterfaceBridged calls virNetDevSetOnline. > > Ahhhh, it's using an ioctl(). > >>>> I need to know why these two devices are down, I believe they were up, your bridge and default-net >>>> looks good. So please show me your kernel message (dmesg), maybe it can give us some useful information. >>> >>> This time veth4 and 5 are down. >>> >>> ---cut--- >> >>> [ 44.158209] IPv6: ADDRCONF(NETDEV_UP): veth4: link is not ready >>> [ 44.473317] IPv6: ADDRCONF(NETDEV_CHANGE): veth4: link becomes ready >>> [ 44.473400] virbr0: topology change detected, propagating >>> [ 44.473407] virbr0: port 5(veth4) entered forwarding state >>> [ 44.473423] virbr0: port 5(veth4) entered forwarding state >> >> veth4 were up here >> >>> [ 44.566186] device veth5 entered promiscuous mode >>> [ 44.571234] IPv6: ADDRCONF(NETDEV_UP): veth5: link is not ready >>> [ 44.571243] virbr0: topology change detected, propagating >>> [ 44.571250] virbr0: port 6(veth5) entered forwarding state >>> [ 44.571261] virbr0: port 6(veth5) entered forwarding state >>> [ 44.902308] IPv6: ADDRCONF(NETDEV_CHANGE): veth5: link becomes ready >>> [ 45.000580] virbr0: port 5(veth4) entered disabled state >> >> and then it became down. >> >>> [ 45.348548] virbr0: port 6(veth5) entered disabled state >> >> So, Some places disable the veth4 and veth5. >> I don't know in which case these two devices will be disabled. >> >> I still can't reproduce this problem in my test bed :( >> I need more information to analyse why these two device being disabled. >> >> So, can you run kernel with the below debug patch? >> >> diff --git a/net/bridge/br_stp_if.c b/net/bridge/br_stp_if.c >> index d45e760..aed319b 100644 >> --- a/net/bridge/br_stp_if.c >> +++ b/net/bridge/br_stp_if.c >> @@ -103,7 +103,7 @@ void br_stp_disable_port(struct net_bridge_port *p) >> p->state = BR_STATE_DISABLED; >> p->topology_change_ack = 0; >> p->config_pending = 0; >> - >> + dump_stack(); >> br_log_state(p); >> br_ifinfo_notify(RTM_NEWLINK, p); >> >> diff --git a/net/core/dev.c b/net/core/dev.c >> index faebb39..9b1617b 100644 >> --- a/net/core/dev.c >> +++ b/net/core/dev.c >> @@ -1368,6 +1368,7 @@ static int dev_close_many(struct list_head *head) >> >> list_for_each_entry(dev, head, unreg_list) { >> rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING); >> + dump_stack(); >> call_netdevice_notifiers(NETDEV_DOWN, dev); >> } >> >> @@ -4729,8 +4730,10 @@ void __dev_notify_flags(struct net_device *dev, unsigned int old_flags) >> if (changes & IFF_UP) { >> if (dev->flags & IFF_UP) >> call_netdevice_notifiers(NETDEV_UP, dev); >> - else >> + else { >> + dump_stack(); >> call_netdevice_notifiers(NETDEV_DOWN, dev); >> + } >> } >> >> if (dev->flags & IFF_UP && >> >> >> Thanks! >> > > There you go: > Thank you very much. > [ 129.084408] CPU: 1 PID: 4473 Comm: ip Not tainted 3.10.0+ #20 > [ 129.084412] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 > [ 129.084415] ffff88003760d000 ffff88003ce7f798 ffffffff8172b2a6 ffff88003ce7f7b8 > [ 129.084419] ffffffff8154be04 ffff88003760d000 0000000000001103 ffff88003ce7f7e8 > [ 129.084422] ffffffff8154be60 0000000000000010 ffff88003760d000 ffff88003ce7f918 > [ 129.084426] Call Trace: > [ 129.084821] virbr0: port 6(veth5) entered disabled state > I can confirm it's the ip command disable the veth device now. but I still don't know who calls ip and why. I search the libvirt code, there are no codes calling "ip link set xxx down". It's so strange... Give you an advice, modify the code of ip(git://git.kernel.org/pub/scm/linux/kernel/git/shemminger/iproute2.git). use read /proc/<getppid>/comm to trace which command calls ip.