seeing this on xenial after this sequence of operations: lxc stop run2 lxc delete run2 lxc copy run1 run2 lxc start run2 <- hangs here, with later dmesg
[337766.146479] unregister_netdevice: waiting for lo to become free. Usage count = 1 [337772.435786] INFO: task lxd:20665 blocked for more than 120 seconds. [337772.435856] Tainted: P OE 4.4.0-47-generic #68-Ubuntu [337772.435922] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [337772.436002] lxd D ffff88006b6cbcb8 0 20665 1 0x00000004 [337772.436006] ffff88006b6cbcb8 ffffffff821d0560 ffff880235aa8000 ffff8801b57d2580 [337772.436009] ffff88006b6cc000 ffffffff81ef5f24 ffff8801b57d2580 00000000ffffffff [337772.436010] ffffffff81ef5f28 ffff88006b6cbcd0 ffffffff81830f15 ffffffff81ef5f20 [337772.436012] Call Trace: [337772.436020] [<ffffffff81830f15>] schedule+0x35/0x80 [337772.436022] [<ffffffff818311be>] schedule_preempt_disabled+0xe/0x10 [337772.436024] [<ffffffff81832df9>] __mutex_lock_slowpath+0xb9/0x130 [337772.436026] [<ffffffff81832e8f>] mutex_lock+0x1f/0x30 [337772.436029] [<ffffffff8171f98e>] copy_net_ns+0x6e/0x120 [337772.436033] [<ffffffff810a148b>] create_new_namespaces+0x11b/0x1d0 [337772.436035] [<ffffffff810a15ad>] copy_namespaces+0x6d/0xa0 [337772.436038] [<ffffffff8107f135>] copy_process+0x905/0x1b70 [337772.436040] [<ffffffff81080530>] _do_fork+0x80/0x360 [337772.436044] [<ffffffff8120bf28>] ? SyS_access+0x1e8/0x230 [337772.436046] [<ffffffff810808b9>] SyS_clone+0x19/0x20 [337772.436048] [<ffffffff81834ff2>] entry_SYSCALL_64_fastpath+0x16/0x71 fwiw, at the time of stop, run2 had an additional IP address on dev lo, and at the time of copy, run1 also was running and had an additional ip address on dev lo -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux-lts-utopic in Ubuntu. https://bugs.launchpad.net/bugs/1403152 Title: unregister_netdevice: waiting for lo to become free. Usage count Status in Linux: Unknown Status in linux package in Ubuntu: Fix Released Status in linux-lts-utopic package in Ubuntu: Confirmed Status in linux-lts-xenial package in Ubuntu: Confirmed Status in linux source package in Trusty: Fix Released Status in linux-lts-utopic source package in Trusty: Fix Released Status in linux-lts-xenial source package in Trusty: Confirmed Status in linux source package in Vivid: Fix Released Bug description: SRU Justification: [Impact] Users of kernels that utilize NFS may see the following messages when shutting down and starting containers: unregister_netdevice: waiting for lo to become free. Usage count = 1 This can cause issues when trying to create net network namespace and thus block a user from creating new containers. [Test Case] Setup multiple containers in parallel to mount and NFS share, create some traffic and shutdown. Eventually you will see the kernel message. Dave's script here: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1403152/comments/24 [Fix] commit de84d89030fa4efa44c02c96c8b4a8176042c4ff upstream -- I currently running trusty latest patches and i get on these hardware and software: Ubuntu 3.13.0-43.72-generic 3.13.11.11 processor : 7 vendor_id : GenuineIntel cpu family : 6 model : 77 model name : Intel(R) Atom(TM) CPU C2758 @ 2.40GHz stepping : 8 microcode : 0x11d cpu MHz : 2400.000 cache size : 1024 KB physical id : 0 siblings : 8 core id : 7 cpu cores : 8 apicid : 14 initial apicid : 14 fpu : yes fpu_exception : yes cpuid level : 11 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm sse4_1 sse4_2 movbe popcnt tsc_deadline_timer aes rdrand lahf_lm 3dnowprefetch arat epb dtherm tpr_shadow vnmi flexpriority ept vpid tsc_adjust smep erms bogomips : 4799.48 clflush size : 64 cache_alignment : 64 address sizes : 36 bits physical, 48 bits virtual power management: somehow reproducable the subjected error, and lxc is working still but not more managable until a reboot. managable means every command hangs. I saw there are alot of bugs but they seams to relate to older version and are closed, so i decided to file a new one? I run alot of machine with trusty an lxc containers but only these kind of machines produces these errors, all other don't show these odd behavior. thx in advance meno To manage notifications about this bug go to: https://bugs.launchpad.net/linux/+bug/1403152/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
