Re: [lguest build regression fix] Re: 2.6.24-rc8-git1: Reported regressions from 2.6.23

[Adrian Bunk <bunk@kernel.org>]

On Sun, Jan 20, 2008 at 10:24:47AM +1100, Rusty Russell wrote:
> On Sunday 20 January 2008 05:06:04 Ingo Molnar wrote:
> > x86 randconfig testing found the following build failure:
> >
> >  arch/x86/lguest/boot.c: In function 'lazy_hcall':
> >  arch/x86/lguest/boot.c:151: error: implicit declaration of function
> > 'paravirt_get_lazy_mode' arch/x86/lguest/boot.c:151: error:
> > 'PARAVIRT_LAZY_NONE' undeclared (first use in this function)
> >
> > which i bisected down to this very fresh commit:
> >
> >  commit 84f7466ee20cc094aa38617abfa2f3834871f054
> >  Author: Rusty Russell <rusty@rustcorp.com.au>
> >  Date:   Sat Jan 19 07:02:29 2008 +1100
> >
> >      Selecting LGUEST should turn on Guest support, as in 2.6.23.
> >
> > which allows the following .config variation:
> >
> >  # CONFIG_PARAVIRT_GUEST is not set
> >  CONFIG_LGUEST_GUEST=y
> 
> This looks like a "randconfig" bug, to be honest.
> 
> CONFIG_LGUEST_GUEST and CONFIG_LGUEST are within "if PARAVIRT_GUEST" (include 
> is in arch/x86/Kconfig).

According to GNU grep we have two CONFIG_LGUEST_GUEST variables (sic), 
one in arch/x86/lguest/Kconfig and one in drivers/lguest/Kconfig.

And CONFIG_LGUEST (which selects CONFIG_LGUEST_GUEST) is in 
drivers/lguest/Kconfig which gets included from drivers/kvm/Kconfig (sic)
which in turn gets included from drivers/Kconfig which in turn is not 
within the "if PARAVIRT_GUEST".

Rusty, don't blame randconfig for finding bugs in this mess you 
created...

> Rusty.

cu
Adrian

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