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client/allocrunner/taskrunner/lifecycle.go

@@ -78,7 +78,9 @@ func (tr *TaskRunner) Kill(ctx context.Context, event *structs.TaskEvent) error
 	tr.EmitEvent(event)
 
 	// Check if the Run method has started yet. If it hasn't we return early,
-	// since the task hasn't even started so there is nothing to wait for
+	// since the task hasn't even started so there is nothing to wait for. This
+	// is still correct since the Run method no-op since the kill context has
+	// already been cancelled.
 	if !tr.hasRunLaunched() {
 		return nil
 	}

client/allocrunner/taskrunner/service_hook.go

@@ -199,6 +199,8 @@ func (h *serviceHook) getTaskServices() *agentconsul.TaskServices {
 // interpolateServices returns an interpolated copy of services and checks with
 // values from the task's environment.
 func interpolateServices(taskEnv *taskenv.TaskEnv, services []*structs.Service) []*structs.Service {
+	// Guard against not having a valid taskEnv. This can be the case if the
+	// Killing or Exited hook is run before post-run.
 	if taskEnv == nil || len(services) == 0 {
 		return nil
 	}