[lxc-users] CRIU with lxc.network.type empty fails

[Tycho Andersen]

Hi Dietmar,

On Wed, Aug 12, 2015 at 05:27:03PM +0200, Dietmar Maurer wrote:
> Here is the requested info:
> 
> # cat /proc/22373/mountinfo
> ...
> 130 225 0:9 / /sys/kernel/debug/tracing rw,relatime - tracefs tracefs rw

Looks like the container has tracefs, which CRIU doesn't understand
natively,

> # cat /proc/self/mountinfo
> 19 24 0:18 / /sys rw,nosuid,nodev,noexec,relatime shared:7 - sysfs sysfs rw
> 20 24 0:4 / /proc rw,nosuid,nodev,noexec,relatime shared:12 - proc proc rw
> 21 24 0:6 / /dev rw,relatime shared:2 - devtmpfs udev
> rw,size=10240k,nr_inodes=4109801,mode=755
> 22 21 0:14 / /dev/pts rw,nosuid,noexec,relatime shared:3 - devpts devpts
> rw,gid=5,mode=620,ptmxmode=000
> 23 24 0:19 / /run rw,nosuid,relatime shared:5 - tmpfs tmpfs
> rw,size=6581364k,mode=755
> 24 0 8:33 / / rw,relatime shared:1 - ext4 /dev/sdc1
> rw,errors=remount-ro,data=ordered
> 25 19 0:12 / /sys/kernel/security rw,nosuid,nodev,noexec,relatime shared:8 -
> securityfs securityfs rw
> 26 21 0:20 / /dev/shm rw,nosuid,nodev shared:4 - tmpfs tmpfs rw
> 27 23 0:21 / /run/lock rw,nosuid,nodev,noexec,relatime shared:6 - tmpfs tmpfs
> rw,size=5120k
> 28 19 0:22 / /sys/fs/cgroup rw shared:9 - tmpfs tmpfs rw,mode=755
> 29 28 0:23 / /sys/fs/cgroup/systemd rw,nosuid,nodev,noexec,relatime shared:10 -
> cgroup cgroup
> rw,xattr,release_agent=/lib/systemd/systemd-cgroups-agent,name=systemd
> 30 19 0:24 / /sys/fs/pstore rw,nosuid,nodev,noexec,relatime shared:11 - pstore
> pstore rw
> 31 28 0:25 / /sys/fs/cgroup/cpuset rw,nosuid,nodev,noexec,relatime shared:13 -
> cgroup cgroup rw,cpuset,clone_children
> 32 28 0:26 / /sys/fs/cgroup/cpu,cpuacct rw,nosuid,nodev,noexec,relatime
> shared:14 - cgroup cgroup rw,cpu,cpuacct
> 33 28 0:27 / /sys/fs/cgroup/blkio rw,nosuid,nodev,noexec,relatime shared:15 -
> cgroup cgroup rw,blkio
> 34 28 0:28 / /sys/fs/cgroup/memory rw,nosuid,nodev,noexec,relatime shared:16 -
> cgroup cgroup rw,memory
> 35 28 0:29 / /sys/fs/cgroup/devices rw,nosuid,nodev,noexec,relatime shared:17 -
> cgroup cgroup rw,devices
> 36 28 0:30 / /sys/fs/cgroup/freezer rw,nosuid,nodev,noexec,relatime shared:18 -
> cgroup cgroup rw,freezer
> 37 28 0:31 / /sys/fs/cgroup/net_cls,net_prio rw,nosuid,nodev,noexec,relatime
> shared:19 - cgroup cgroup rw,net_cls,net_prio
> 38 28 0:32 / /sys/fs/cgroup/perf_event rw,nosuid,nodev,noexec,relatime shared:20
> - cgroup cgroup
> rw,perf_event,release_agent=/run/cgmanager/agents/cgm-release-agent.perf_event
> 39 28 0:33 / /sys/fs/cgroup/hugetlb rw,nosuid,nodev,noexec,relatime shared:21 -
> cgroup cgroup
> rw,hugetlb,release_agent=/run/cgmanager/agents/cgm-release-agent.hugetlb
> 40 20 0:34 / /proc/sys/fs/binfmt_misc rw,relatime shared:22 - autofs systemd-1
> rw,fd=22,pgrp=1,timeout=300,minproto=5,maxproto=5,direct
> 41 21 0:17 / /dev/mqueue rw,relatime shared:23 - mqueue mqueue rw
> 43 19 0:7 / /sys/kernel/debug rw,relatime shared:24 - debugfs debugfs rw
> 42 21 0:35 / /dev/hugepages rw,relatime shared:25 - hugetlbfs hugetlbfs rw
> 44 19 0:36 / /sys/fs/fuse/connections rw,relatime shared:26 - fusectl fusectl rw
> 103 23 0:45 / /run/rpc_pipefs rw,relatime shared:83 - rpc_pipefs rpc_pipefs rw
> 107 23 0:47 / /run/cgmanager/fs rw,relatime shared:87 - tmpfs cgmfs
> rw,size=100k,mode=755
> 111 24 0:49 / /var/lib/lxcfs rw,nosuid,nodev,relatime shared:89 - fuse.lxcfs
> lxcfs rw,user_id=0,group_id=0,allow_other
> 113 23 0:50 / /run/user/0 rw,nosuid,nodev,relatime shared:91 - tmpfs tmpfs
> rw,size=3290684k,mode=700

..and it's not bind mounted from the host, which is why it's not being
autodetected as a bind mount. When I start both trusty and wily
containers I don't see anything mounting tracefs, do you know what is
mounting it?

Unmounting it should allow you to c/r. We could add c/r to CRIU for
tracefs, although I've never used it, so I'll have to read about it a
bit.

Tycho