user-sessions: rely on PID 1 to kill sessions

As we want to centralized cgroup access we should stop killing the user
sessions directly from the systemd-user-sessions service. Instead, rely
on PID 1 doing this by adding the right ordering dependencies to the
session scope units.

1 files changed, 15 insertions, 0 deletions

diff --git a/src/login/logind-dbus.c b/src/login/logind-dbus.c
index ec46fdc232..39af637d1b 100644
--- a/src/login/logind-dbus.c
+++ b/src/login/logind-dbus.c
@@ -2518,6 +2518,7 @@ int manager_start_scope(
                 pid_t pid,
                 const char *slice,
                 const char *description,
+                const char *after,
                 DBusError *error,
                 char **job) {
 
@@ -2575,6 +2576,20 @@ int manager_start_scope(
                         return log_oom();
         }
 
+        if (!isempty(after)) {
+                const char *after_property = "After";
+
+                if (!dbus_message_iter_open_container(&sub, DBUS_TYPE_STRUCT, NULL, &sub2) ||
+                    !dbus_message_iter_append_basic(&sub2, DBUS_TYPE_STRING, &after_property) ||
+                    !dbus_message_iter_open_container(&sub2, DBUS_TYPE_VARIANT, "as", &sub3) ||
+                    !dbus_message_iter_open_container(&sub3, DBUS_TYPE_ARRAY, "s", &sub4) ||
+                    !dbus_message_iter_append_basic(&sub4, DBUS_TYPE_STRING, &after) ||
+                    !dbus_message_iter_close_container(&sub3, &sub4) ||
+                    !dbus_message_iter_close_container(&sub2, &sub3) ||
+                    !dbus_message_iter_close_container(&sub, &sub2))
+                        return log_oom();
+        }
+
         /* cgroup empty notification is not available in containers
          * currently. To make this less problematic, let's shorten the
          * stop timeout for sessions, so that we don't wait