linux-kernel - Re: ACPI "Soft-off" power button only rebooting system, not powering off

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Message-Id: <E1KgL3s-0003oM-2a@be1.7eggert.dyndns.org>
Date:	Thu, 18 Sep 2008 17:04:51 +0200
From:	Bodo Eggert <7eggert@....de>
To:	Simon Farnsworth <simon@...nz.org.uk>,
	linux-kernel@...r.kernel.org, Pavel Machek <pavel@...e.cz>,
	Andrew Paprocki <andrew@...iboo.com>,
	LKML <linux-kernel@...r.kernel.org>
Subject: Re: ACPI "Soft-off" power button only rebooting system, not powering    off

Simon Farnsworth <simon@...nz.org.uk> wrote:
>>>>> On Wed 2008-09-17 00:50:03, Andrew Paprocki wrote:

>>>>>> I have an AMD / Award BIOS based system which does not properly shut
>>>>>> off when I hold down the power button for 4 seconds. The BIOS is
>>>>>> configured to have "Soft-off" set to "Delay for 4 seconds" which is
>>>>>> supposed to power the machine off if the button is held that long.

> If you hold it down for 4 or more seconds, the BIOS is supposed to shut
> the machine down without the OS knowing what's happening (no ACPI
> events, just a loss of power). From your problem description, the BIOS
> is noticing *something* about the way Linux sets things up, and
> *choosing* to reboot instead of cutting the power.

Each MB I know takes about eight seconds of pressing the power button to
switch "off". Besides that, having a four-seconds-delay seems rather useless
if you'd switch from "0s -> shutdown, 4 s -> hard shutdown" to "0 s ->
suspend, 4 s -> hard shutdown". I never tried it myself*, but I'd expect
"0 s-> suspend, 4 s -> shutdown, 8 s -> hard shutdown".

If I happen to be correct here, you'd be looking at the wrong side of the
correct tree.


*)I'd fail, because I put in a relais, which would cut the power anyway.


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