The code for rebooting an SMP machine doesn't always work (still)

Billy Newsom billy at
Wed Feb 21 19:14:52 UTC 2007

Kris Kennaway wrote:
> On Tue, Feb 20, 2007 at 06:21:52PM -0600, Billy Newsom wrote:
>> When a SMP machine does not have an AT keyboard controller, there needs 
>> to be a way to reboot the machine under FreeBSD!
> Like the sysctl that was added in 6.2?
> hw.acpi.handle_reboot=1
> Kris

Well, what do you know? That works for this machine! I will probably 
blog this information sometime. That is excellent. Finally, the ACPI 
code has come up to standard in FreeBSD. It seems like it was lacking 
for a number of years.

As for the old reboot code, I still think it could use some help. I 
happen to think that the code which tries to reboot the machine using 
the triple fault should work if it was adjusted somehow. But since we 
are fully ACPI compliant, this hack works great.

In any case, the Mac Pro needs that sysctl variable under FreeBSD 6.2 or 
  we get that awful trap 12 doing a reboot.

With this change, I think we have an acceptable server platform, made by 
Apple, run by free software. Pretty slick system. Maybe I will post my 
dmesg now.

Thanks community!

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