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get_minimal_required_cuda_ver_from_ptx_ver rejects PTX ISA 9.4 (CUDA 13.4) #3336
Description
Is this a duplicate?
- I confirmed there appear to be no duplicate issues for this bug and that I agree to the Code of Conduct
Type of Bug
Runtime Error
Component
cuda.bindings
Describe the bug
cuda.bindings.utils.get_minimal_required_cuda_ver_from_ptx_ver raises for PTX produced by the CUDA 13.4 toolchain, because _ptx_to_cuda in cuda/bindings/utils/_ptx_utils.py ends at "9.3": (13, 3). The PTX ISA release history lists PTX ISA 9.4 with CUDA 13.4 (driver r615).
How to Reproduce
cuda-bindings 13.4.4 with nvidia-cuda-nvrtc 13.4 (no GPU needed):
from cuda.bindings import nvrtc
from cuda.bindings.utils import get_ptx_ver, get_minimal_required_cuda_ver_from_ptx_ver
err, prog = nvrtc.nvrtcCreateProgram(b'extern "C" __global__ void k(){}', b"k.cu", 0, [], [])
nvrtc.nvrtcCompileProgram(prog, 1, [b"-arch=compute_90"])
err, n = nvrtc.nvrtcGetPTXSize(prog)
buf = b" " * n
nvrtc.nvrtcGetPTX(prog, buf)
ver = get_ptx_ver(buf.decode()) # "9.4"
get_minimal_required_cuda_ver_from_ptx_ver(ver)ValueError: Unknown or unsupported PTX ISA version: 9.4
Expected behavior
13040.
Operating System
Ubuntu 24.04, aarch64
nvidia-smi output
Not GPU-specific; NVRTC only, no GPU needed.
Proposed fix
I have a fix ready: the "9.4": (13, 4) entry, a 9.4 case in test_ptx_utils and a release note. The same line would be needed on the 13.4.x branch. Happy to open a PR if you assign this to me.
Activity
leofang commentedon Nov 3, 2026
@rwgk @mdboom we missed this during 13.4 bring-up. I believe updating the table is documented in Ralf's (internal) bring-up manual.
rwgk commentedon Nov 3, 2026
Yes. It just easily falls through the cracks. Not sure what to do about it. I think we need a minimal reminder on the public side, to inspect the internal documentation as part of release preparation.
rwgk commentedon Nov 3, 2026
I assigned this issue to myself: I created PR #3348 already. In hindsight, it's a super obvious and simple way to ensure this doesn't happen again in the future. (Excuses omitted.)
leofang commentedon Nov 3, 2026
No worries, I suppose we can add an item to the release checklist. Future ourselves and agents should be able to pick it up :)