Feedback on Releases — 23.01 New Features and Changes - Errata/Known Hardware Issues for 4860 & 8860
The errata notes Devices based on “ADI” or “RCC” hardware, such as the 4860, 8860, and potentially other similar models, may have issues with the ichsmb0 and/or ehci0 devices encountering an interrupt loop, leading to higher than usual CPU usage (NG 8916). This can typically be worked around by disabling the affected device.
Advice in this forum post [https://forum.netgate.com/post/1084616] is that disabling ichsmb0 only disables the LED status indicator which is considered non-critical.
Also in this forum post [https://forum.netgate.com/post/1088752] advice is that disabling ehci0 disables the eMMC drive which is considered critical unless the user has another drive on the system as the system will not boot.
This forum post [https://forum.netgate.com/post/1088800] advises to only disable the ichsmb0 as it should resolve the problem.
The current wording of the errata indicates that either device can be disabled, but make no mention of the impacts of disabling either device. A user could therefore proceed to disable the ehci0 device without realising the consequences. The errata should be updated to note the consequences of disabling either device, with a clear warning of the impact of disabling the ehci0 device given the potentially critical outcome if it is disabled.
If disabling the ehci0 device is not considered necessary to resolve the issue, then reference to the ehci0 device should be removed from the errata to avoid ambiguity and confusion.