Re: [RFC][PATCH 2/2] first callers of process_deny_checkpoint()

[Ingo Molnar <mingo@elte.hu>]

* Rafael J. Wysocki <rjw@sisk.pl> wrote:

> > > Surely not ACPI-compliant.
> > 
> > what do you mean?
> 
> The ACPI spec says quite specifically what should be done while 
> entering hibernation and during resume from hibernation.  We're not 
> following that in the current code, but we can (gradually) update the 
> code to become ACPI-compilant in that respect.  However, if we go the 
> checkpointing route, I don't think that will be possible any more.

ah, i see. I did not mean to utilize any ACPI paths but simple powerdown 
or reboot.

If we checkpoint all apps to persistent disk areas (which the checkpoint 
patches in this thread are about), then we can just reboot the kernel 
and forget all its state.

That capability can be used to build a really robust hibernation 
implementation IMO: we could "hibernate/kexec" over between different 
kernel versions transparently. (only a small delay will be noticed by 
the user - if we do it smartly with in-kernel modesetting then not even 
the screen contents will be changed over this.)

	Ingo