RELENG_6 power button ignored after halt if ACPI enabled

Bruno Ducrot ducrot at poupinou.org
Sat Sep 23 10:02:51 PDT 2006


On Thu, Sep 21, 2006 at 03:28:55PM -0700, Nate Lawson wrote:
> Wilkinson, Alex wrote:
> >    0n Sun, Sep 17, 2006 at 10:29:26PM -0700, Nate Lawson wrote: 
> >
> >    >Try setting this sysctl:
> >    >sysctl hw.acpi.disable_on_reboot=1
> >    >
> >    >It may be that you need acpi to stop managing your power button after 
> >    halt.
> >
> >I dont get it ? I thought you needed ACPI to do the actual shutdown ?
> 
> He isn't doing halt -p, he's doing "halt", then hitting the power 
> button.  If acpi is still enabled, it intercepts the button event but 
> can't do anything because the OS is halted (i.e. no shutdown() 
> available).  If ACPI is disabled by that point, the BIOS handles it and 
> powers off the system.
> 
> This only applies to his system, it's not necessarily true in general. 
> Some systems won't work if ACPI is disabled during this process, hence 
> the sysctl.
> 
> Just goes to show how complicated this all is, but it's not MY fault.  :)
> 

When ACPI mode is enabled, the system should power off after 4 seconds IIRC.

-- 
Bruno Ducrot

--  Which is worse:  ignorance or apathy?
--  Don't know.  Don't care.


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