Re: [PATCH v2 15/16] objtool/powerpc: Enable objtool to be built on ppc

[Naveen N. Rao]

Christophe Leroy wrote:
> Le 29/08/2022 à 07:52, Sathvika Vasireddy a écrit :
> > diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
> > index 4c466acdc70d..dc05cd23c233 100644
> > --- a/arch/powerpc/Kconfig
> > +++ b/arch/powerpc/Kconfig
> > @@ -237,6 +237,7 @@ config PPC
> >   	select HAVE_MOD_ARCH_SPECIFIC
> >   	select HAVE_NMI				if PERF_EVENTS || (PPC64 && PPC_BOOK3S)
> >   	select HAVE_OPTPROBES
> > +	select HAVE_OBJTOOL			if PPC32 || MPROFILE_KERNEL
>
> Why restrict it to MPROFILE_KERNEL ? In your RFC it was for all PPC64.
>
> Recent discussion on the list shows new problem with recordmcount, see 
> https://lore.kernel.org/all/MW5PR84MB184250EA1CAE04497C1E7CE9AB769@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/
>
> Those ones are with ppc64 big endian, so objtool would be welcome here 
> as well.

I don't think adding support for objtool on ppc64 elfv1 is a good idea. 
While it might solve the immediate issue with recordmcount, I worry that 
the function descriptors and dot symbols in ppc64 elfv1 might throw up 
issues in the future causing maintenance overhead.


- Naveen