Re: [PATCH] PM: Fix dependencies of CONFIG_SUSPEND and CONFIG_HIBERNATION (updated 2x)

["Rafael J. Wysocki" <rjw@sisk.pl>]

On Thursday, 9 August 2007 00:03, Andrew Morton wrote:
> On Tue, 7 Aug 2007 00:23:26 +0200
> "Rafael J. Wysocki" <rjw@sisk.pl> wrote:
> 
> > Dependencies of CONFIG_SUSPEND and CONFIG_HIBERNATION introduced by commit
> > 296699de6bdc717189a331ab6bbe90e05c94db06 "Introduce CONFIG_SUSPEND for
> > suspend-to-Ram and standby" are incorrect, as they don't cover the facts that
> > (1) not all architectures support suspend and (2) SMP hibernation is only
> > possible on X86 and PPC64 (if CONFIG_PPC64_SWSUSP is set).
> > 
> > Moreover, SMP suspend and hibernation are only possible if CONFIG_HOTPLUG is
> > set, because they select HOTPLUG_CPU that depends on it. __Also, since suspend
> > and hibernation don't depend on EXPERIMENTAL, arrange things so that CPU
> > hotplug can be selected if it is not set.
> 
> The version of this which I have (version eighty eight, afaict :),
> reproduced below) breaks ia64 allmodconfig:
> 
> init/Kconfig:416:error: found recursive dependency: HOTPLUG -> SUSPEND_SMP_POSSIBLE -> PM_SLEEP_SMP -> HOTPLUG_CPU -> HOTPLUG
>  -> PCCARD -> PCMCIA -> USB_ARCH_HAS_HCD -> MOUSE_APPLETOUCH -> USB -> USB_SISUS

Well, I have no idea how this is even possible.

On ia64 HOTPLUG_CPU depends only on SMP && EXPERIMENTAL and the patch doesn't
change that.  Moreover, SUSPEND_SMP_POSSIBLE cannot be set on ia64, either with the
patch or without it.

Anyway, I'm going to drop the "HOTPLUG depends on PM_SLEEP_SMP" bits and retest
with allmodconfig on everyting I can test.

BTW, the patch is needed to fix compilation problems on PPC.

Greetings,
Rafael


-- 
"Premature optimization is the root of all evil." - Donald Knuth