I strongly suspect that this is a High Sierra bug but really I don't know. I hope to fix this myself but I don't have a clue.
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Edit: I now think this a bug in User-Approved Kernel Extension Loading. The kexts will load when permission is granted in Security Preferences, but they won't load after a reboot.
I filed a bug which Apple people may find in Radar
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My driver stack has three kernel extensions. Normally two of them always load while the third loads when my USB dongle is attached.
If I install this product on a totally clean High Sierra install, then none of them will load after rebooting. This persists through many reboots.
Forcing a kext cache rebuild has no effect:
$ sudo touch /System/Library/Extensions
However if High Sierra has been used for a while, or if High Sierra is installed on top of Sierra, then the kernel extensions load just fine.
My client is a fabless semiconductor firm; their customers are all peripherals manufacturers. This bug was found by a customer in a product that until now had been working really, really well.
Please help me, O Obi Wan K'Stackoverflow'i. You're my only hope!
Dumbfoundedly,
Mike
