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

[Tycho Andersen]

Hi Dietmar,

On Sun, Aug 09, 2015 at 12:35:03PM +0200, Dietmar Maurer wrote:
> Hi all,
> 
> I am testing criu with latest lxc/criu code from git, and the
> ubuntu 4.1 kernel. I use the following lxc config:
> 
> # cat /var/lib/lxc/500/config
> lxc.arch = amd64
> lxc.include = /usr/share/lxc/config/centos.common.conf
> lxc.tty = 0
> lxc.utsname = CT500
> lxc.cgroup.memory.limit_in_bytes = 536870912
> lxc.cgroup.memory.memsw.limit_in_bytes = 1073741824
> lxc.cgroup.cpu.shares = 1024
> lxc.rootfs = loop:/var/lib/vz/images/500/vm-500-rootfs.raw
> lxc.console = none
> lxc.cgroup.devices.deny = c 5:1 rwm
> lxc.network.type = empty
> 
> but criu fails:
> 
> # strace lxc-checkpoint -s -v -D /tmp/checkpoint -n 500
> 
> clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD,
> child_tidptr=0x7fcf28886a50) = 1591
> close(4)                                = 0
> wait4(1591, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], 0, NULL) = 1591
> --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=1591, si_uid=0,
> si_status=0, si_utime=0, si_stime=0} ---
> fcntl(3, F_GETFL)                       = 0 (flags O_RDONLY)
> fstat(3, {st_mode=S_IFIFO|0600, st_size=0, ...}) = 0
> mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) =
> 0x7fcf288a3000
> lseek(3, 0, SEEK_CUR)                   = -1 ESPIPE (Illegal seek)
> read(3, "Version: 1.6\nGitID: v1.6-175-g4a"..., 4096) = 38
> close(3)                                = 0
> munmap(0x7fcf288a3000, 4096)            = 0
> geteuid()                               = 0
> write(2, "lxc-checkpoint: ", 16lxc-checkpoint: )        = 16
> write(2, "criu.c: criu_ok: 308 ", 21criu.c: criu_ok: 308 )   = 21
> write(2, "Found network that is not VETH o"..., 39Found network that is not VETH
> or NONE
> ) = 39
> write(2, "\n", 1
> )                       = 1
> write(2, "Checkpointing 500 failed.\n", 26Checkpointing 500 failed.
> ) = 26
> exit_group(1)                           = ?
> 
> 
> Is that expected?

No, it's just an oversight. Unfortunately it's not as simple as adding
empty networks to the whitelist for LXC, but I'll work on a patch and
try and send it today.

Tycho