[3.13] gh-71936: Fix race condition in multiprocessing.Pool (GH-124973) #126869
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…124973) * pythongh-71936: Fix race condition in multiprocessing.Pool Proxes of shared objects register a Finalizer in BaseProxy._incref(), and it will call BaseProxy._decref() when it is GCed. This may cause a race condition with Pool(maxtasksperchild=None) on Windows. A connection would be closed and raised TypeError when a GC occurs between _ConnectionBase._check_writable() and _ConnectionBase._send_bytes() in _ConnectionBase.send() in the second or later task, and a new object is allocated that shares the id() of a previously deleted one. Instead of using the id() of the token (or the proxy), use a unique, non-reusable number. (cherry picked from commit ba088c8) Co-authored-by: Petr Viktorin <encukou@gmail.com> Co-Authored-By: Akinori Hattori <hattya@gmail.com>
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Proxes of shared objects register a Finalizer in BaseProxy._incref(), and it
will call BaseProxy._decref() when it is GCed. This may cause a race condition
with Pool(maxtasksperchild=None) on Windows.
A connection would be closed and raised TypeError when a GC occurs between
_ConnectionBase._check_writable() and _ConnectionBase._send_bytes() in
_ConnectionBase.send() in the second or later task, and a new object
is allocated that shares the id() of a previously deleted one.
Instead of using the id() of the token (or the proxy), use a unique,
non-reusable number.
(cherry picked from commit ba088c8)
Co-authored-by: Petr Viktorin encukou@gmail.com
Co-Authored-By: Akinori Hattori hattya@gmail.com