Re: [PATCH] Enhance checkpoint/restart Kconfig options

[Dave Hansen <dave-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>]

On Thu, 2009-06-04 at 15:01 -0500, Nathan Lynch wrote:
> Dave Hansen <dave-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org> writes:
> > diff -puN checkpoint/Kconfig~cr-kconfig-fixup checkpoint/Kconfig
> > --- linux-2.6.git/checkpoint/Kconfig~cr-kconfig-fixup	2009-06-04 11:38:57.000000000 -0700
> > +++ linux-2.6.git-dave/checkpoint/Kconfig	2009-06-04 11:38:57.000000000 -0700
> > @@ -7,9 +7,14 @@ config DEFERQUEUE
> >  	default n
> >  
> >  config CHECKPOINT
> > -	bool "Enable checkpoint/restart (EXPERIMENTAL)"
> > +	bool "Checkpoint/restart (EXPERIMENTAL)"
> >  	depends on CHECKPOINT_SUPPORT && EXPERIMENTAL
> >  	select DEFERQUEUE
> > +	select UTS_NS
> > +	select IPC_NS
> > +	select NET_NS
> > +	select PID_NS
> > +	select USER_NS
> 
> *_NS all depend on NAMESPACES at the very least; some have additional
> dependencies.  Selecting a symbol without ensuring its dependencies are
> enabled is one way to break a build.

Ahh, but there *isn't* a strict build dependency on them.  We just want
to make sure that if they're available that we enable them.  If we have
CONFIG_NET=n, then we certainly don't want to make CHECKPOINT depends on
it.  

> Also - checkpoint is useful without *_NS, no?  Forcing these things on
> seems a little user-hostile..

I think the hostile thing is trying to completely unshare all the
namespaces without checking to see which ones are enabled, first. ;)

-- Dave