Re: EFI reboot vs. ACPI reboot (was: Re: [tip:x86/urgent] x86/reboot, efi: Use EFI reboot for Acer TravelMate X514-51T)

From: Ingo Molnar
Date: Wed Apr 17 2019 - 15:17:09 EST



* Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> wrote:

> On Wed, 17 Apr 2019 at 11:23, Ingo Molnar <mingo@xxxxxxxxxx> wrote:
> >
> >
> > * Prakhya, Sai Praneeth <sai.praneeth.prakhya@xxxxxxxxx> wrote:
> >
> > > I will ask around internally to check if it is a good idea to make EFI
> > > reboot the default method when the machine is booted in EFI mode.
> >
> > Or whether there's some robust signature that indicates "modern EFI
> > system where EFI reboot is the primary method"?
> >
> > Major EFI version or ACPI version or such?
> >
>
> I am actually at Microsoft right now, and I managed to get
> clarification on how Windows deals with this: Windows will attempt to
> use ACPI reboot first, and will only attempt to use anything else if
> that fails. EFI reset is actually its least preferred option, and so
> it is highly likely that it is untested on most of the shipping x86
> hardware if any of the other methods work.
>
> So let's not touch this.

Agreed and that's really useful information, thanks!

Ingo