Noryungi's Journal: Installing OpenBSD 4.3 on an HP machine : ACPI workaround

I have been asked to make a (really) small Jabber server on a small HP machine.

Installing OpenBSD 4.3 on the machine was fairly simple and uneventful, but the fecal matter hit the rotating oscillator when I first rebooted the machine.

Almost as soon as the machine was starting, the OpenBSD kernel crashed and dropped me into its integrated debugger (with a ddb> prompt).

Not good.

Thankfully, Google is your friend, and entering "OpenBSD HP PC crash kernel" immediately gives you the correct answer. By the way, do read the entire page, as it contains a fairly nice explanation on how to recover from a crash, not just an ACPI-related one.

So, if you install OpenBSD 4.3 on an HP machine, and the kernel crashes almost immediately, try the following, it worked for me:

1. Once at the ddb> prompt, type boot reboot (Try typing help for more information on the functions of the integrated debugger).
2. Once the machine has rebooted, you have a few seconds to type -c at the boot> prompt. The kernel itself is booted very fast, so hurry up as soon as the boot> prompt appears!
3. The OpenBSD kernel is then launched, but does not probe the hardware. Instead, it stops and displays a UKC>/ (User Kernel Configuration) prompt.
4. On the UKC> prompt, type disable 426 or disable acpiprt*. The kernel should then respond "426 acpiprt* disabled".
5. Type quit to quit the UKC> prompt and save your changes temporarily. You can try list to see all the drivers contained in the OpenBSD kernel or help for more information on the functions of the UKC.
6. The kernel should then boot normally.
7. To make this change permanent, and avoid having to do this every time you reboot the machine, make sure you read the excellent OpenBSD FAQ, and enter config -u -f -e /bsd as root.
8. Your OpenBSD kernel is now in activity and should avoid crashes at the next reboot.

That's it! Hope this helps someone...

Once again: OpenBSD rocks and its documentation really is top-notch.

Doing this under Linux would require passing boot arguments (disable acpi?) at the LILO or GRUB prompt, but this is pure speculation on my part.