It is not an error to fail to register the Docker factory on a system
running only rkt, and vice-versa, so these failures are downgraded from
an Error to a Warning. The raw handler should always be registered.
This ensures each goroutine is given its own Netlink connection, and
presumably avoids having a message destined for one goroutine read by
another goroutine.
If in getCgroupPath in cgroups we have some other hierarchies after
"devices" using ".*" sometimes will cause matching wrong string as
a container path so we need negated character class here: "[^:]*".
e.g.
If cgroups string is
"153:name=systemd:/system.slice/docker-f55e7cad1fcc02f992e0c33c210ecdc6d641858a665f28370523c27c05bdde0e.scope,4:freezer,devices,name=container:/system.slice/docker-f55e7cad1fcc02f992e0c33c210ecdc6d641858a665f28370523c27c05bdde0e.scope,3:cpuacct,cpu,cpuset,name=fairsched:/system.slice/docker-f55e7cad1fcc02f992e0c33c210ecdc6d641858a665f28370523c27c05bdde0e.scope,2:memory:/system.slice/docker-f55e7cad1fcc02f992e0c33c210ecdc6d641858a665f28370523c27c05bdde0e.scope,1:blkio,name=beancounter:/system.slice/docker-f55e7cad1fcc02f992e0c33c210ecdc6d641858a665f28370523c27c05bdde0e.scope"
match[1] will be "blkio" but not:
/system.slice/docker-f55e7cad1fcc02f992e0c33c210ecdc6d641858a665f28370523c27c05bdde0e.scope
These fixes the commit:
4cbd91c761 Make getCgroupPath work in case of named or multi- hierarchies
v2: use negated character class, correct the example, remove .* on
either end as they don't do anything in FindSubmatch.
In case we have devices hierarchies mounted in named cgroup
or together with other hierarchy regexp parse will fail.
So after "devices" and before ":" can be name of cgroup or
other hierarchies names.
E.g.:
1) remount cgroups:
umount /sys/fs/cgroup/devices
mkdir /sys/fs/cgroup/named_cgroup
mount -n -t cgroup -o devices,name=named_cgroup cgroup
/sys/fs/cgroup/named_cgroup
2) add some task to nested device cgroup and check ps output
mkdir /sys/fs/cgroup/named_cgroup/test.slice
sleep 1000 &
[1] 22734
echo 22734 > /sys/fs/cgroup/named_cgroup/test.slice/tasks
ps -ao pid,cgroup | grep 22734
22734
14:devices,name=named_cgroup:/test.slice,1:name=systemd:/user.slice/user-1000.slice/session-1.scope
Signed-off-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
