HP P420i HBA mode missing drives

From: Andreas Kempe <kempe_at_lysator.liu.se>
Date: Sat, 16 Dec 2023 17:19:58 UTC

We are using an HPE SL4540 with an HP P420i raid controller with 60 HP
branded SAS drives. When configuring the raid controller for HBA mode,
i.e. passthrough of the drives to the OS, we only get 56 drives, with
four missing. The missing drives are drives 27 through 30 in bay 1.
Booting Linux on the machine instead of FreeBSD gives us all 60 drives
visible to Linux.

I've attached the output of camcontrol devlist.

Does anyone have any clue what could cause this?

Best regards,
Andreas Kempe