From 29474a993e9ef0b50a25cab943beaf853d1ef0b6 Mon Sep 17 00:00:00 2001 From: Kumar Aditya Date: Thu, 13 Mar 2025 00:11:52 +0530 Subject: [PATCH] gh-131141: fix data race in instrumentation while registering callback (#131142) --- .../2025-03-12-11-19-46.gh-issue-131141.tQz594.rst | 1 + Python/instrumentation.c | 7 ++++--- 2 files changed, 5 insertions(+), 3 deletions(-) create mode 100644 Misc/NEWS.d/next/Core_and_Builtins/2025-03-12-11-19-46.gh-issue-131141.tQz594.rst diff --git a/Misc/NEWS.d/next/Core_and_Builtins/2025-03-12-11-19-46.gh-issue-131141.tQz594.rst b/Misc/NEWS.d/next/Core_and_Builtins/2025-03-12-11-19-46.gh-issue-131141.tQz594.rst new file mode 100644 index 00000000000000..c1ea679864fb15 --- /dev/null +++ b/Misc/NEWS.d/next/Core_and_Builtins/2025-03-12-11-19-46.gh-issue-131141.tQz594.rst @@ -0,0 +1 @@ +Fix data race in :data:`sys.monitoring` instrumentation while registering callback. diff --git a/Python/instrumentation.c b/Python/instrumentation.c index 3481b5df14288b..d4bca27f22cd74 100644 --- a/Python/instrumentation.c +++ b/Python/instrumentation.c @@ -1399,9 +1399,10 @@ _PyMonitoring_RegisterCallback(int tool_id, int event_id, PyObject *obj) PyInterpreterState *is = _PyInterpreterState_GET(); assert(0 <= tool_id && tool_id < PY_MONITORING_TOOL_IDS); assert(0 <= event_id && event_id < _PY_MONITORING_EVENTS); - PyObject *callback = _Py_atomic_exchange_ptr(&is->monitoring_callables[tool_id][event_id], - Py_XNewRef(obj)); - + _PyEval_StopTheWorld(is); + PyObject *callback = is->monitoring_callables[tool_id][event_id]; + is->monitoring_callables[tool_id][event_id] = Py_XNewRef(obj); + _PyEval_StartTheWorld(is); return callback; }