6.x acpi powerbutton

[Stephen Clark]

Nate Lawson wrote:
> Ian Smith wrote:
>> On Fri, 10 Apr 2009, Nate Lawson wrote:
>>  > Andriy Gapon wrote:
>>  > > on 09/04/2009 23:24 Stephen Clark said the following:
>>  > >> Is there a reason it doesn't send and event like Linux that can be acted
>>  > >> upon by user space other
>>  > >> than signaling init? I like to have a message written in
>>  > >> /var/log/messages that someone pressed
>>  > >> the powerbutton.
>>  > > 
>>  > > I think that for all suspend states except S5 userland is notified via
>>  > > devd mechanism and potentially can veto the suspend. S5 (soft-off) is
>>  > > coded to start shutdown immediately. You can try to hack on
>>  > > acpi_ReqSleepState in sys/dev/acpica/acpi.c.
>>  > > 
>>  > > I am not sure what is the reason for this special behavior of S5. But I
>>  > > like it, because it sometimes allows me to perform semi-clean shutdown
>>  > > when X goes crazy. But I also see when it could be useful to have S5
>>  > > request go through userland. So this could be configurable.
>>  > 
>>  > The reason for userland getting into the loop in the first place was to
>>  > run programs to shut down devices and reinit them after resume. This
>>  > isn't necessary in the shutdown case because init already sends a
>>  > signal, as you mention.
>>  > 
>>  > There's already a mechanism for timing out if userland is not
>>  > responding, so a suspend will ultimately happen whether or not it
>>  > answers. However, that waits for a while (1 minute?) and devd used to be
>>  > optional, so I thought it best to keep the existing S5 behavior
>>  > (immediate shutdown).
>>  > 
>>  > It may be ok to enable this for S5 but I don't think it's very useful.
>>
>> Perhaps a silly question, but is it too late at this stage of the game 
>> to try logging S5 events to syslog before dying?  I agree with Stephen, 
>> logging 'shutdown by powerbutton' surely beats what might otherwise 
>> resemble a spontaneous reboot?  Or is something already logged here?
> 
> I'm not resisting this, but I'm having trouble seeing the importance.
> What happens differently than if someone hits CTRL-ALT-DEL on a virtual
> console?
> 
Hi Nate,

We have over 500 units in the field that are used as firewall/vpn/routers. They 
have no console, but they do have a powerbutton. We have had customers say the 
machine turned itself off. It would be nice to know that someone pressed the 
power button.

Thanks,
Steve

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