nspawn: move payload to sub-cgroup first, then sync cgroup trees

if we sync the legacy and unified trees before moving to the right
subcgroup then ultimately the cgroup paths in the hierarchies will be
out-of-sync... Hence, let's move the payload first, and sync then.

Addresses: https://github.com/systemd/systemd/pull/9762#issuecomment-441187979

diff --git a/src/nspawn/nspawn.c b/src/nspawn/nspawn.c
index 5cb049e5f734fe4ac6dd2e32405388182976f93a..64a30a5b9a800bce23932b4488fcae1b949fc998 100644 (file)
--- a/src/nspawn/nspawn.c
+++ b/src/nspawn/nspawn.c
@@ -3962,11 +3962,11 @@ static int run(int master,
         } else if (arg_slice || arg_property)
                 log_notice("Machine and scope registration turned off, --slice= and --property= settings will have no effect.");
 
-        r = sync_cgroup(*pid, arg_unified_cgroup_hierarchy, arg_uid_shift);
+        r = create_subcgroup(*pid, arg_keep_unit, arg_unified_cgroup_hierarchy);
         if (r < 0)
                 return r;
 
-        r = create_subcgroup(*pid, arg_keep_unit, arg_unified_cgroup_hierarchy);
+        r = sync_cgroup(*pid, arg_unified_cgroup_hierarchy, arg_uid_shift);
         if (r < 0)
                 return r;