Only invoke hotplug socket when functionality is enabled (#952)

Alters hotplug hook to have a query mechanism checking if the
functionality is enabled. This allows us to avoid using the hotplug
socket and service when hotplug is disabled.

1 files changed, 7 insertions, 2 deletions

diff --git a/tools/hook-hotplug b/tools/hook-hotplug
index 34e95929..ced268b3 100755
--- a/tools/hook-hotplug
+++ b/tools/hook-hotplug
@@ -8,12 +8,17 @@ is_finished() {
     [ -e /run/cloud-init/result.json ]
 }
 
-if is_finished; then
+hotplug_enabled() {
+    [ "$(cloud-init devel hotplug-hook -s "${SUBSYSTEM}" query)" == "enabled" ]
+}
+
+if is_finished && hotplug_enabled; then
     # open cloud-init's hotplug-hook fifo rw
     exec 3<>/run/cloud-init/hook-hotplug-cmd
     env_params=(
-        --devpath="${DEVPATH}"
         --subsystem="${SUBSYSTEM}"
+        handle
+        --devpath="${DEVPATH}"
         --udevaction="${ACTION}"
     )
     # write params to cloud-init's hotplug-hook fifo