[master 4/24] Teardown all devices before tearing disk images down

[dashea]

From: Vratislav Podzimek

DM maps cannot be removed while they are in use so in order to make them
removable, we need to teardown all devices "built" on top of them first. Since
we don't support using disk images together with real disks we can safely just
tear all devices down. This makes our examples (and possibly some tests) better
clean after themselves.
---
 blivet/devicetree.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/blivet/devicetree.py b/blivet/devicetree.py
index fe10aa5..953d977 100644
--- a/blivet/devicetree.py
+++ b/blivet/devicetree.py
@@ -1048,6 +1048,9 @@ def setup_disk_images(self):

def teardown_disk_images(self):
         """ Tear down any disk image stacks. """
+        # teardown all devices first so that there's nothing active running on
+        # top of disk images when we try to tear those down
+        self.teardown_all()
         self._populator.teardown_disk_images()

@property