From 4394e0db24f38250d487adcbd8b85f314cb86829 Mon Sep 17 00:00:00 2001 From: Antoine Pitrou Date: Wed, 27 Apr 2011 19:20:48 +0200 Subject: =?UTF-8?q?Issue=20#10517:=20After=20fork(),=20reinitialize=20the?= =?UTF-8?q?=20TLS=20used=20by=20the=20PyGILState=5F*=20APIs,=20to=20avoid?= =?UTF-8?q?=20a=20crash=20with=20the=20pthread=20implementation=20in=20RHE?= =?UTF-8?q?L=205.=20=20Patch=20by=20Charles-Fran=C3=A7ois=20Natali.?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- Include/pystate.h | 1 + Misc/NEWS | 4 ++++ Modules/signalmodule.c | 1 + Python/pystate.c | 17 +++++++++++++++++ 4 files changed, 23 insertions(+) diff --git a/Include/pystate.h b/Include/pystate.h index b9fe61e..729342c 100644 --- a/Include/pystate.h +++ b/Include/pystate.h @@ -111,6 +111,7 @@ PyAPI_FUNC(void) PyThreadState_Clear(PyThreadState *); PyAPI_FUNC(void) PyThreadState_Delete(PyThreadState *); #ifdef WITH_THREAD PyAPI_FUNC(void) PyThreadState_DeleteCurrent(void); +PyAPI_FUNC(void) _PyGILState_Reinit(void); #endif PyAPI_FUNC(PyThreadState *) PyThreadState_Get(void); diff --git a/Misc/NEWS b/Misc/NEWS index 4c57348..3850505 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -61,6 +61,10 @@ Core and Builtins Library ------- +- Issue #10517: After fork(), reinitialize the TLS used by the PyGILState_* + APIs, to avoid a crash with the pthread implementation in RHEL 5. Patch + by Charles-François Natali. + - Issue #11763: don't use difflib in TestCase.assertMultiLineEqual if the strings are too long. diff --git a/Modules/signalmodule.c b/Modules/signalmodule.c index f306bba..6f021e7 100644 --- a/Modules/signalmodule.c +++ b/Modules/signalmodule.c @@ -976,6 +976,7 @@ void PyOS_AfterFork(void) { #ifdef WITH_THREAD + _PyGILState_Reinit(); PyEval_ReInitThreads(); main_thread = PyThread_get_thread_ident(); main_pid = getpid(); diff --git a/Python/pystate.c b/Python/pystate.c index ddb7d42..3eefa36 100644 --- a/Python/pystate.c +++ b/Python/pystate.c @@ -537,6 +537,23 @@ _PyGILState_Fini(void) autoInterpreterState = NULL; } +/* Reset the TLS key - called by PyOS_AfterFork. + * This should not be necessary, but some - buggy - pthread implementations + * don't flush TLS on fork, see issue #10517. + */ +void +_PyGILState_Reinit(void) +{ + PyThreadState *tstate = PyGILState_GetThisThreadState(); + PyThread_delete_key(autoTLSkey); + if ((autoTLSkey = PyThread_create_key()) == -1) + Py_FatalError("Could not allocate TLS entry"); + + /* re-associate the current thread state with the new key */ + if (PyThread_set_key_value(autoTLSkey, (void *)tstate) < 0) + Py_FatalError("Couldn't create autoTLSkey mapping"); +} + /* When a thread state is created for a thread by some mechanism other than PyGILState_Ensure, it's important that the GILState machinery knows about it so it doesn't try to create another thread state for the thread (this is -- cgit v0.12