Re: [PATCH] hyperv: fix build if KEXEC not enabled

[Ingo Molnar <mingo@kernel.org>]

* Vitaly Kuznetsov <vkuznets@redhat.com> wrote:

> Stephen Hemminger <stephen@networkplumber.org> writes:
> 
> > Fixes regression 4.3 mergw window in my config 
> > where hyperv is enable but CONFIG_KEXEC not enabled.
> >
> > arch/x86/kernel/cpu/mshyperv.c:112: undefined reference to `native_machine_crash_shutdown'
> >
> > Introduced by:
> >    commit b4370df2b1f5158de028e167974263c5757b34a6
> >    Author: Vitaly Kuznetsov <vkuznets@redhat.com>
> >    Date:   Sat Aug 1 16:08:09 2015 -0700
> >
> >        Drivers: hv: vmbus: add special crash handler
> >
> > Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
> >
> > --- a/arch/x86/kernel/cpu/mshyperv.c	2015-09-07 10:11:24.994885115 -0700
> > +++ b/arch/x86/kernel/cpu/mshyperv.c	2015-09-07 10:14:20.995698615 -0700
> > @@ -109,7 +109,9 @@ static void hv_machine_crash_shutdown(st
> >  {
> >  	if (hv_crash_handler)
> >  		hv_crash_handler(regs);
> > +#ifdef CONFIG_KEXEC
> >  	native_machine_crash_shutdown(regs);
> > +#endif
> >  }
> 
> Greg in particular was against #ifdefs in C code and I sent the
> following patch to fix the issue:
> 
> https://lkml.org/lkml/2015/8/11/417

Note that this is still somewhat buggy, the whole hv_machine_crash_shutdown() 
should be conditional - like in kvmclock.c.

Thanks,

	Ingo