From 8b9049d8c66160eeb3b7ea60be3c34a752b5fce2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marek=20Marczykowski-G=C3=B3recki?=
 <marmarek@invisiblethingslab.com>
Date: Mon, 11 Jan 2016 21:53:33 +0100
Subject: [PATCH] core/hvm: create `root-cow.img` if it's missing

It should be created at VM creation time (or template changes commit).
But for example for HVM templates created before implementing
QubesOS/qubes-issues#1573, there would be no such image. So create it
when needed, just before VM startup

Fixes QubesOS/qubes-issues#1602
---
 core/storage/xen.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/core/storage/xen.py b/core/storage/xen.py
index 3edf0f22..9ea7ba73 100644
--- a/core/storage/xen.py
+++ b/core/storage/xen.py
@@ -226,6 +226,8 @@ class XenStorage(QubesVmStorage):
                     raise QubesException(
                         "VM '{}' holding '{}' does not exists".format(
                             drive_domain, drive_path))
+        if self.rootcow_img and not os.path.exists(self.rootcow_img):
+            self.commit_template_changes()
 
 
 class XenPool(Pool):