Disabled PCIe devices (sysfs enable==0) carry no data traffic; their
link state has no operational impact. Switchtec PCIe switch management
endpoints on NVIDIA HGX H100 baseboards (and similar fabric controllers)
train at reduced speed intentionally and were producing spurious warnings.
Check is vendor-agnostic: reads enable attribute via existing helper,
no vendor/device ID hardcoding.
Documented in bible-local/decisions/2026-06-12-pcie-disabled-device-link-warning.md.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>