From 93688e953115cbd32789bd7f8be8ef50a4124748 Mon Sep 17 00:00:00 2001
From: Julia Kreger <juliaashleykreger@gmail.com>
Date: Tue, 23 May 2023 10:39:20 -0700
Subject: [PATCH] Explicitly use a session for DB version check

The db field value version check, which is a preflight to
major upgrades (to detect if a prior upgrade was not completed)
was using model_query, which could orphan an open transaction in
the same process until the python interpretter went and took out
the perverable trash.

We now use an explicit session which structurally ensures we close
any open transactions which allows a metadata lock to be obtained
to perform a schema update..

Change-Id: Id51419bc50af5a756bb7b0ca451df1936dd6f904
---
 ironic/db/sqlalchemy/api.py                           | 11 ++++++-----
 ...ove-model-query-from-upgrade-af227b6c8a5d654a.yaml |  9 +++++++++
 2 files changed, 15 insertions(+), 5 deletions(-)
 create mode 100644 releasenotes/notes/remove-model-query-from-upgrade-af227b6c8a5d654a.yaml

diff --git a/ironic/db/sqlalchemy/api.py b/ironic/db/sqlalchemy/api.py
index 6658a8ef1b..96f2dc45fd 100644
--- a/ironic/db/sqlalchemy/api.py
+++ b/ironic/db/sqlalchemy/api.py
@@ -1798,11 +1798,12 @@ class Connection(api.Connection):
             #             compatible with its (old) DB representation.
             # NOTE(rloo): .notin_ does not handle null:
             # http://docs.sqlalchemy.org/en/latest/core/sqlelement.html#sqlalchemy.sql.operators.ColumnOperators.notin_
-            query = model_query(model.version).filter(
-                sql.or_(model.version == sql.null(),
-                        model.version.notin_(supported_versions)))
-            if query.count():
-                return False
+            with _session_for_read() as session:
+                query = session.query(model.version).filter(
+                    sql.or_(model.version == sql.null(),
+                            model.version.notin_(supported_versions)))
+                if query.count():
+                    return False
 
         return True
 
diff --git a/releasenotes/notes/remove-model-query-from-upgrade-af227b6c8a5d654a.yaml b/releasenotes/notes/remove-model-query-from-upgrade-af227b6c8a5d654a.yaml
new file mode 100644
index 0000000000..270dc85c26
--- /dev/null
+++ b/releasenotes/notes/remove-model-query-from-upgrade-af227b6c8a5d654a.yaml
@@ -0,0 +1,9 @@
+---
+fixes:
+  - |
+    Fixes an issue where the database upgrade can hang on Python 3.10.
+    This was because open transactions could become orphaned awaiting
+    the Python runtime to clean up their memory references due to the
+    way the overall database query was being intiiated to pre-flight
+    check the upgrade. We have structurally changed the behavior
+    to remedy this case.