On Friday, 14 October 2016 15:48:47 CEST Mark Kettenis wrote:
> > Date: Fri, 14 Oct 2016 16:49:31 +0900 (JST)
> > From: YASUOKA Masahiko <yasu...@openbsd.org>
> > Hi,
> > I'm working on NEC Express5800/R110h-1 (dmesg is attached). On this
> > machine, our kernel panics with following message.
> > cpu0 at mainbus0panic: cpu at apic id 0 already attached?
> > This seems to happen since x2APIC on the machine is enabled by BIOS
> > and the kernel doesn't assume that. The diff makes the kernel use
> > x2APIC if it is enabled by BIOS.
> > ok?
> is the APICBASE msr available on all amd64 machines? If not, it will
> need to be protected with a CPUID check.
Yes. I have looked that up before, for its use in the suspend/resume code.