criu doesn't save permissions on all cgroups visible to the container

[Mark Gavalda]

I tried the same live migration that I described in https://bugs.launchpad.net/ubuntu/+source/criu/+bug/1605664 but this time with CRIU 2.4 compiled from source code on both machines, now it failed with the following:

//Sending VM
error: Error transferring container data: migration restore failed
(00.669220) 1: Error (files-reg.c:1509): File sys/fs/cgroup/systemd has bad mode 040755 (expect 040775)
(00.723370) Error (cr-restore.c:991): 28507 exited, status=1
(00.764229) Error (cr-restore.c:1857): Restoring FAILED.

//Receiving VM syslog:
Jul 22 15:37:57 instance-4 lxd[4040]: t=2016-07-22T15:37:57+0000 lvl=eror msg="Error during migration sink" err="migration restore failed\n(00.669220) 1: Error (files-reg.c:1509): File sys/fs/cgroup/systemd has bad mode 040755 (expect 040775)\n(00.723370) Error (cr-restore.c:991): 28507 exited, status=1\n(00.764229) Error (cr-restore.c:1857): Restoring FAILED."

Ubuntu 16.04, CRIU version 2.4

[Tycho Andersen (tycho-s)]

Hi,

Sorry for the delay. As I mentioned here: https://github.com/xemul/criu/issues/210 I've got patches that fix this for CRIU and liblxc, and I'm waiting on comments from upstream.

[Tycho Andersen (tycho-s)]

The CRIU and liblxc patches have been merged, now we need releases for both :)

[Tycho Andersen (tycho-s)]

I believe all the necessary fixes for this are in 2.7 and liblxc 2.0.5; CRIU 2.7 isn't in the archive yet, but hopefully will be soon.

[Ed McDonagh (ed-mcdonagh)]

Is CRIU going to be updated in xenial? It is still at 2.0 vs 2.6 in yakkety. And by implication is live migration never going to work reliably in xenial without PPAs?