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It said "the TPM as an entropy source" without condition. In 6.18, tpm_crb sets TPM_CHIP_FLAG_HWRNG_DISABLED on every AMD firmware TPM that is not Pluton (tpm_crb.c:887-892, AMD's PA-410), and tpm_add_hwrng then registers nothing (tpm-chip.c:536-556). A discrete TPM, as tpm_tis drives, and Pluton keep their hwrng.
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Docs only: one sentence in docs/hardening.md. The base is zbook-batch-3 (#641), which also edits this file. It retargets when #641 lands.
The file said "the TPM as an entropy source" without condition. At v6.18.56:
tpm_crb.c:887-892setsTPM_CHIP_FLAG_HWRNG_DISABLEDon every AMD machine whose CRB TPM is not Pluton ("A quirk for https://www.amd.com/en/support/kb/faq/pa-410").tpm_is_hwrng_enabled()andtpm_add_hwrng()(tpm-chip.c:536-556) then register notpm-rng-N.A discrete TPM (tpm_tis) and Pluton keep it. The ZBook 8 G1ak's Nuvoton chip is expected to be discrete; the hardware report's
tpm:line (#634) shows which hwrng is current.This is the audit's tpm-report:6. Its other half is the comment at
build/config/kernel/hardening.fragment:192("The TPM, as an entropy source."), which is the integrator's file. It is left for whenever the fragment next changes, as a comment-only edit would still change the kernel's inputs.