Arm backend: Pin pybind11 version when installing tosa_serialization

[tom-arm]

• To account for potential edge cases of pybind11 drifting
• Will be removed when tosa-tools is installed from pypi

Change-Id: I197d3c141bd8918a8debaba55adcdc9fb296ba17

cc @digantdesai @freddan80 @per @zingo @oscarandersson8218 @mansnils @Sebastian-Larsson @robell

[pytorch-bot]

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❌ 5 New Failures, 1 Cancelled Job, 1 Pending, 1 Unrelated Failure

As of commit 48d0a73 with merge base e458023 ():

NEW FAILURES - The following jobs have failed:

• pull / test-llama-runner-qnn-linux (fp32, qnn_16a16w, qnn) / linux-job (gh)
  RuntimeError: Command docker exec -t 7f9d977f97b2e6a2e1aa0ad3f4b309ea8a2b46a6e855330d9e36e09d2088af46 /exec failed with exit code 92
• pull / test-samsung-models-linux / linux-job (gh)
  RuntimeError: Command docker exec -t a5ea91af40fa84592b261d0dce8b81b6424188b9ea7a628250ef6cc3dec190fe /exec failed with exit code 1
• pull / test-samsung-quantmodels-linux / linux-job (gh)
  RuntimeError: Command docker exec -t 9ae55e39fa89033d89fd73f06a3de05203ad9a3ff6ace3ea8dd5624b420b87ae /exec failed with exit code 1
• trunk / test-qnn-model (fp32, vit) / linux-job (gh)
  RuntimeError: Command docker exec -t 87e235c3b395b3716aabcd034232e1004937e73e7798b66fe03aa36bc9c10d30 /exec failed with exit code 92
• trunk / test-qnn-optimum-model (fp32, albert) / linux-job (gh)
  RuntimeError: Command docker exec -t 284499d0c53672c8bb365d17ecb6d9af3f3d45a4ccac4bffd5c16da588dafe36 /exec failed with exit code 92

CANCELLED JOB - The following job was cancelled. Please retry:

• trunk / test-mcu-cortex-m-backend / linux-job (gh)
  ##[error]The operation was canceled.

FLAKY - The following job failed but was likely due to flakiness present on trunk:

• pull / test-models-linux (add, xnnpack-quantization-delegation, linux.2xlarge) / linux-job (gh) (matched linux rule in flaky-rules.json)
  The process '/usr/bin/git' failed with exit code 1

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[Copilot]

Pull request overview

Pins pybind11 to a specific version to make local/CI installation of tosa_serialization more deterministic and avoid issues from dependency drift until tosa-tools can be installed from PyPI.

Changes:

• Add pybind11==2.10.4 to the ARM TOSA requirements file.
• Explicitly install pybind11==2.10.4 in the Linux CMake unit test CI script before installing tosa_serialization.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
backends/arm/requirements-arm-tosa.txt	Pins pybind11 for ARM/TOSA dependency installs.
.ci/scripts/unittest-linux-cmake.sh	Installs pinned pybind11 in CI prior to building/installing tosa_serialization.

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[Copilot]

The pybind11 version is pinned here, but the same version is also hard-coded in .ci/scripts/unittest-linux-cmake.sh. This duplication is easy to let drift and can create CI vs local setup mismatches. Consider centralizing the pin (e.g., a shared constraints file or having CI install from this requirements file) or add an explicit note that the CI script must be kept in sync.

Suggested change

	ai-edge-model-explorer >= 0.1.16
	ai-edge-model-explorer >= 0.1.16
	# NOTE: pybind11 version must be kept in sync with .ci/scripts/unittest-linux-cmake.sh

[Copilot]

This pybind11 pin duplicates the version in backends/arm/requirements-arm-tosa.txt. To reduce the chance of the two pins diverging, consider deriving the version from a single source (e.g., install -r backends/arm/requirements-arm-tosa.txt/a shared constraints file, or define a single variable that both paths use).

Suggested change

	python -m pip install pybind11==2.10.4
	python -m pip install -r backends/arm/requirements-arm-tosa.txt

[tom-arm]

This will install unnecessary dependencies, so I will not take this suggestion

[zingo]

This reverts a previous fix we had the we remove last week but it is still needed so we are putting it back again. Sorry for the pingponging with this.

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated no new comments.

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