Use C++ shared_ptr for IPC file descriptor cleanup#1832
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Andy-Jost merged 4 commits intoNVIDIA:mainfrom Mar 30, 2026
Merged
Use C++ shared_ptr for IPC file descriptor cleanup#1832Andy-Jost merged 4 commits intoNVIDIA:mainfrom
Andy-Jost merged 4 commits intoNVIDIA:mainfrom
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Replace Python-level os.close() in IPCAllocationHandle with a C++ shared_ptr custom deleter that calls POSIX close() directly, avoiding unraisable exception errors during late interpreter shutdown. Made-with: Cursor
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Made-with: Cursor
Made-with: Cursor
create_fd_handle and create_fd_handle_ref throw std::runtime_error on Windows since POSIX file descriptors are Linux-only. Made-with: Cursor
rwgk
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Mar 30, 2026
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Looks good to me (manual review + Cursor).
Cursor GPT-5.3 Codex High flagged: I don’t see a dedicated automated test for the specific regression (“late interpreter shutdown / unraisable os.close path”).
I think that's fine to ignore. I've seen the "Error in sys.excepthook" messages many times, we definitely have plenty of indirect coverage.
cpcloud
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The C++ fd-handle cleanup approach looks correct and preserves the IPC ownership model while avoiding late-interpreter-shutdown issues.
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Summary
When a
DeviceMemoryResourceis destroyed after Python finalization has begun, its IPC allocation handle (a POSIX file descriptor on Linux) must still be closed. Previously,IPCAllocationHandle.__dealloc__calledos.close()to do this, but during late interpreter shutdown theosmodule may already be partially torn down, producing cryptic "Error in sys.excepthook" messages about unraisable exceptions.This PR fixes the problem by managing the file descriptor through a C++
shared_ptrwith a custom deleter that calls POSIXclose()directly, bypassing Python entirely. The newFileDescriptorHandlefollows the same pattern as other handle types in theresource_handlesmodule.Changes
resource_handles.hpp/cpp— addFileDescriptorHandletypedef,create_fd_handle(owning, calls::close),create_fd_handle_ref(non-owning),as_intptrandas_pyoverloads_resource_handles.pxd/pyx— declare and expose the new handle type and factory functions_ipc.pxd/pyx— replaceint _handlewithFileDescriptorHandle _h_fd;close()becomesreset(); remove__dealloc__Test Plan
sys.excepthookerrors after test runMade with Cursor