diff --git a/bitbake/lib/bb/utils.py b/bitbake/lib/bb/utils.py
index 992e200641..3a4b29181e 100644
--- a/bitbake/lib/bb/utils.py
+++ b/bitbake/lib/bb/utils.py
@@ -1882,6 +1882,7 @@ def path_is_descendant(descendant, ancestor):
 @contextmanager
 def lock_timeout(lock):
     try:
+        s = signal.pthread_sigmask(signal.SIG_BLOCK, signal.valid_signals())
         held = lock.acquire(timeout=5*60)
         if not held:
             bb.server.process.serverlog("Couldn't get the lock for 5 mins, timed out, exiting.\n%s" % traceback.format_stack())
@@ -1889,3 +1890,4 @@ def lock_timeout(lock):
         yield held
     finally:
         lock.release()
+        signal.pthread_sigmask(signal.SIG_SETMASK, s)