From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dilip Daya Subject: Re: Network namespace and bonding WARNING at fs/proc/generic.c remove_proc_entry Date: Fri, 06 Jul 2012 14:01:47 -0400 Message-ID: <1341597707.2829.23.camel@pro6455b.example.com> References: <1340900320.3441.88.camel@pro6455b.example.com> <20120705220749.GA11255@mail.hallyn.com> <87ehopu3e5.fsf@xmission.com> <20120706170538.GA31679@mail.hallyn.com> Reply-To: dilip.daya-VXdhtT5mjnY@public.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, "Eric W. Biederman" , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: "Serge E. Hallyn" Return-path: In-Reply-To: <20120706170538.GA31679-7LNsyQBKDXoIagZqoN9o3w@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org List-Id: netdev.vger.kernel.org Hi Serge, On Fri, 2012-07-06 at 17:05 +0000, Serge E. Hallyn wrote: > Quoting Eric W. Biederman (ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org): > > "Serge E. Hallyn" writes: > > > > > Quoting Dilip Daya (dilip.daya-VXdhtT5mjnY@public.gmane.org): > > >> Hi, > > >> > > >> I'd discussed the following with Serge Hallyn. > > >> > > >> => Environment based on 3.2.18 / x86_64 kernel. > > >> => WARNING: at fs/proc/generic.c:808 remove_proc_entry+0xdb/0x21f() > > >> => WARNING: at fs/proc/generic.c:849 remove_proc_entry+0x208/0x21f() > > > > > > Hi, > > > > > > thanks much for sending this. I'm still getting this error on > > > 3.5.0-2-generic (today's ubuntu quantal kernel) > > > > > >> network namespace and bonding > > >> ----------------------------- > > >> > > >> * Migrate two phy nics from host to netns (netns0). > > >> - ip link set ethX netns netns0 > > >> > > >> * In host environment: > > >> - load bonding module, /sbin/modprobe -v bonding mode=1 miimon=100 > > >> - /sys/class/net/bond0 exists. > > >> - /proc/net/bonding/bond0 exists. > > >> - /sys/class/net/bonding_masters has bond0. > > >> > > >> * Migrate bond0 to netns (netns0): > > >> - ip link set bond0 netns netns0. > > >> > > >> * Within netns (netns0): > > >> - /sys/class/net/bonding_masters is empty. > > >> - /sys/class/net/bond0 exist. > > >> - configure bond0 and ifenslave with two phy nics. > > >> - /proc/net/bonding/bond0 does not exist within netns0, but does > > >> exist in the host environment. > > >> - /sys/class/net/bonding_masters is empty. > > > > > > mine is not empty, fwiw. However > > > > > >> - ping to remote end of bond0 works. > > >> > > >> * Within netns (netns0), flushing ethX and bondY: > > >> - down bond0 and its phy nic interfaces: > > >> - ip link set ... down > > >> - ip addr flush dev [bond0 | eth#] > > >> - deleting bond0, /sbin/ip link del dev bond0 > > > > > > Yup I still get a remove_proc_entry WARNING at fs/proc/generic.c:808, > > > which is the warning when (!de) > > > > It looks like Dilip is running an old kernel. There should have been > > some version of /sys/class/net/bonding_masters in every network > > namespace since sometime in 2009. > > > > >From the warning it looks like the proc files are being added/removed > > to the wrong network namespace. So in one namespace we get an error > > when we delete the moved device and in the other network namespace > > we get an error when we remove the /proc/directory. > > > > An old kernel without proper network namespace support is the only > > reason I can imagine someone would be moving an existing bond device > > between network namespaces. > > > > If there are other reasons for wanting to move a bonding device between > > network namespaces it is possible to catch the NETDEV_UNREGISTER and > > NETDEV_REGISTER events to remove/add the per device proc files at the > > appropriate time. > > > > However since moving bonding devices appears to be an unneded operation > > let's just do things simply and forbid moving bonding devices between > > network namespaces. Serge, Dilip can you two test the patch below > > and see if it fixes the warnings. > > > > Eric > > > > > > diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c > > index 2ee8cf9..818ed64 100644 > > --- a/drivers/net/bonding/bond_main.c > > +++ b/drivers/net/bonding/bond_main.c > > @@ -4345,6 +4345,9 @@ static void bond_setup(struct net_device *bond_dev) > > bond_dev->priv_flags |= IFF_BONDING; > > bond_dev->priv_flags &= ~(IFF_XMIT_DST_RELEASE | IFF_TX_SKB_SHARING); > > > > + /* Don't allow bond devices to change network namespaces. */ > > + bond_dev->features |= NETIF_F_LOCAL; > > I believe this needs to be NETIF_F_NETNS_LOCAL. Test build still going with > that change. Correct, I made that change and rebuilt bonding driver: # modinfo bonding | head filename: /lib/modules/3.2.18-clim-3-amd64/kernel/drivers/net/bonding/bonding.ko alias: rtnl-link-bond author: Thomas Davis, tadavis-/3juihCSby0@public.gmane.org and many others description: Ethernet Channel Bonding Driver, v3.7.1-netns version: 3.7.1-netns ... My results with the above bonding driver: (1) Migrating bond0 from host to netns: # ip link set bond0 netns netns0 RTNETLINK answers: Invalid argument => cannot migrate bond0 from host to netns. => No warnings. (2) Loading bonding module in host environment and unloading bonding module from within netns: # modprobe -v -r bonding # rmmod /lib/modules/3.2.18-clim-3-amd64/kernel/drivers/net/bonding/bonding.ko # lsmod | grep bond <<< bonding module does not exist >>> # ll /sys/class/net/ total 0 lrwxrwxrwx 1 root root 0 Jul 6 11:00 lo -> ../../devices/virtual/net/lo/ lrwxrwxrwx 1 root root 0 Jul 6 11:00 eth7 -> ../../devices/pci0000:00/0000:00:05.0/0000:14:00.1/net/eth7/ lrwxrwxrwx 1 root root 0 Jul 6 11:00 eth6 -> ../../devices/pci0000:00/0000:00:05.0/0000:14:00.0/net/eth6/ => No warnings. -DilipD.