Re: 2.6.25-rc2 System no longer powers off after suspend-to-disk. Screen becomes green.

Rafael J. Wysocki
2008-02-22T17:46:24Z

On Friday, 22 of February 2008, Mark Lord wrote:
> Rafael J. Wysocki wrote:
> > On Friday, 22 of February 2008, Mark Lord wrote:
> >> david@lang.hm wrote:
> >> ..
> >>> I've been watching for kexec hibernate for a little while now, and the
> >>> last I saw was that acpi was incompatible with the kexec hibernate (but
> >>> the suspend folks were still claiming that devices needed to be put in
> >>> the 'right mode' not just powered off. I've been waiting to see this
> >>> resolved.
> >> ..
> >>
> >> Yeah, exactly. What's so special about poweroff on hibernation?
> >> Why even bother with the special "S4" state there?
> >
> > (1) To be able to wake up with the help of devices that can't wake
> > the system up from S5 (power off)
> > (2) To handle some platform devices appropriately over the cycle
> ..
>
> That's the theory. I've read about it, but have yet to imagine
> any real-life situation where it applies.
>
> But this isn't my speciality, so.. do you have experience with any real examples?

Yup. The fan in my notebook behaves incorrectly after a resume from
hibernation if S5 is entered instead of S4 during it.

I don't know why exactly it happens, but that's how it goes.

Also, some machines are reported to behave incorrectly after a "shutdown"
mode hibernation, while the same machines work just fine after a "platform"
mode hibernation. So at least for these machines it seems to matter.

Thanks,
Rafael