diff --git a/src/calibre/utils/test_lock.py b/src/calibre/utils/test_lock.py
index 2e73653fcf..0bf23e2428 100644
--- a/src/calibre/utils/test_lock.py
+++ b/src/calibre/utils/test_lock.py
@@ -136,6 +136,10 @@ class IPCLockTest(unittest.TestCase):
         tdirs = []
         while not tdirs:
             tdirs = list(tdirs_in('t', check_for_lock=True))
+        for i in range(5):
+            if is_tdir_locked(tdirs[0]):
+                break
+            time.sleep(1)
         self.assertTrue(is_tdir_locked(tdirs[0]))
         c2 = run_worker('calibre.utils.test_lock', 'other5')
         c2.wait()