diff --git a/server/montytest/api.py b/server/montytest/api.py
index e465c165..24e0b7ff 100644
--- a/server/montytest/api.py
+++ b/server/montytest/api.py
@@ -34,7 +34,7 @@
 according to the route/URL mapping defined in `__init__.py`.
 """
 
-WORKER_VERSION = 11
+WORKER_VERSION = 12
 
 
 @exception_view_config(HTTPException)
diff --git a/worker/sri.txt b/worker/sri.txt
index b2f6a693..76c1162b 100644
--- a/worker/sri.txt
+++ b/worker/sri.txt
@@ -1 +1 @@
-{"__version": 11, "updater.py": "gSJX/HbsPwsZnUZaFbAgF0zwWPWXv+LEw9jBhJkxFOrCH9CZS0+4U4nE2fJdeNze", "worker.py": "5H/vhWvrKp34ehp12ppQWXr0lYOQT1lHs8qjHg2XX02oLHZtMkO9iyK1IgVCwVqa", "games.py": "SOlAX95oLMYwCKNm/XkK5Uf1WPw1PGeIPzvgZqZ04AHNF2+MQ1vc+blTGu5F0JUZ"}
+{"__version": 12, "updater.py": "gSJX/HbsPwsZnUZaFbAgF0zwWPWXv+LEw9jBhJkxFOrCH9CZS0+4U4nE2fJdeNze", "worker.py": "0fvv6AahgRpu9pjF/xgjdVWjRujuecreJJ9Pyw8yyqfLY8aQ+nhZQlLll4/fWj/k", "games.py": "SOlAX95oLMYwCKNm/XkK5Uf1WPw1PGeIPzvgZqZ04AHNF2+MQ1vc+blTGu5F0JUZ"}
diff --git a/worker/worker.py b/worker/worker.py
index 57648ed8..92277ad0 100644
--- a/worker/worker.py
+++ b/worker/worker.py
@@ -65,7 +65,7 @@
 MIN_CARGO_MAJOR = 1
 MIN_CARGO_MINOR = 77
 
-WORKER_VERSION = 11
+WORKER_VERSION = 12
 FILE_LIST = ["updater.py", "worker.py", "games.py"]
 HTTP_TIMEOUT = 30.0
 INITIAL_RETRY_TIME = 15.0
@@ -1172,7 +1172,7 @@ def utcoffset():
     return "{}{:02d}:{:02d}".format("+" if utcoffset >= 0 else "-", hh, mm)
 
 
-def verify_worker_version(remote, username, password):
+def verify_worker_version(remote, username, password, worker_lock):
     # Returns:
     # True: we are the right version and have the correct credentials
     # False: incorrect credentials (the user may have been blocked in the meantime)
@@ -1191,6 +1191,7 @@ def verify_worker_version(remote, username, password):
         print("Updating worker version to {}".format(req["version"]))
         backup_log()
         try:
+            worker_lock.release()
             update()
         except Exception as e:
             print(
@@ -1211,6 +1212,7 @@ def fetch_and_handle_task(
     current_state,
     clear_binaries,
     global_cache,
+    worker_lock,
 ):
     # This function should normally not raise exceptions.
     # Unusual conditions are handled by returning False.
@@ -1225,7 +1227,7 @@ def fetch_and_handle_task(
     )
 
     # Check the worker version and upgrade if necessary
-    ret = verify_worker_version(remote, worker_info["username"], password)
+    ret = verify_worker_version(remote, worker_info["username"], password, worker_lock)
     if ret is False:
         current_state["alive"] = False
     if not ret:
@@ -1464,7 +1466,12 @@ def worker():
 
     # Check the worker version and upgrade if necessary
     try:
-        if verify_worker_version(remote, options.username, options.password) is False:
+        if (
+            verify_worker_version(
+                remote, options.username, options.password, worker_lock
+            )
+            is False
+        ):
             return 1
     except Exception as e:
         print("Exception verifying worker version:\n", e, sep="", file=sys.stderr)
@@ -1562,6 +1569,7 @@ def worker():
             current_state,
             clear_binaries,
             options.global_cache,
+            worker_lock,
         )
         if not current_state["alive"]:  # the user may have pressed Ctrl-C...
             break