gh-159462: Relax the thread check in _PyMem_mi_page_reclaimed() (gh-159807)

Author: corona10

Lib/test/test_free_threading/test_interpreters.py

@@ -1,6 +1,7 @@
 import textwrap
 import unittest
 
+from test import support
 from test.support import import_helper, script_helper
 
 
@@ -24,6 +25,19 @@ def test_destroy_subinterpreter_does_not_abort(self):
         """)
         script_helper.assert_python_ok('-c', script)
 
+    @support.requires_resource('cpu')
+    def test_destroy_subinterpreter_with_abandoned_pages_does_not_abort(self):
+        # gh-159462: Py_EndInterpreter() clears a non-current thread state.
+        script = textwrap.dedent("""
+            import _testinternalcapi
+
+            interpid = _testinternalcapi.create_interpreter()
+            _testinternalcapi.exec_interpreter(
+                interpid, "objs = [[i] for i in range(400_000)]; del objs")
+            _testinternalcapi.destroy_interpreter(interpid, basic=True)
+        """)
+        script_helper.assert_python_ok('-c', script)
+
 
 if __name__ == "__main__":
     unittest.main()

Objects/obmalloc.c

@@ -212,7 +212,10 @@ _PyMem_mi_page_reclaimed(mi_page_t *page)
         if (mi_page_all_free(page)) {
             assert(page->qsbr_node.next == NULL);
             _PyThreadStateImpl *tstate = tstate_from_heap(mi_page_heap(page));
-            assert(tstate == (_PyThreadStateImpl *)_PyThreadState_GET());
+            // gh-159462: the owning tstate may differ from the current
+            // one, but the heap is always owned by the current OS thread,
+            // so the page list is not shared with other OS threads.
+            assert(mi_page_heap(page)->thread_id == _Py_ThreadId());
             page->retire_expire = 0;
             llist_insert_tail(&tstate->mimalloc.page_list, &page->qsbr_node);
         }