Re: [PATCH RFC v9 05/51] x86/coco: move CONFIG_HAS_CC_PLATFORM check down into coco/Makefile

[Tom Lendacky]

On 7/9/23 22:05, Sathyanarayanan Kuppuswamy wrote:
> Hi,
>
> On 6/11/23 9:25 PM, Michael Roth wrote:
> > Currently CONFIG_HAS_CC_PLATFORM is a prereq for building anything in
> > arch/x86/coco, but that is generally only applicable for guest support.>
> > For SEV-SNP, helpers related purely to host support will also live in
> > arch/x86/coco. To allow for CoCo-related host support code in
> > arch/x86/coco, move that check down into the Makefile and check for it
> > specifically when needed.
>
>
> I think CONFIG_HAS_CC_PLATFORM is not meant to be guest specific (otherwise,

Correct, it is used in bare-metal for SME support, so that needs to 
continue to work.

Thanks,
Tom

> we could have named it CONFIG_HAS_CC_GUEST). Will it create any issue if
> we enable it in host?
>
> > Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
> > Suggested-by: Tom Lendacky <thomas.lendacky@xxxxxxx>
> > Signed-off-by: Michael Roth <michael.roth@xxxxxxx>
> > ---
> >   arch/x86/Kbuild        | 2 +-
> >   arch/x86/coco/Makefile | 2 +-
> >   2 files changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/arch/x86/Kbuild b/arch/x86/Kbuild
> > index 5a83da703e87..1889cef48b58 100644
> > --- a/arch/x86/Kbuild
> > +++ b/arch/x86/Kbuild
> > @@ -1,5 +1,5 @@
> >   # SPDX-License-Identifier: GPL-2.0
> > -obj-$(CONFIG_ARCH_HAS_CC_PLATFORM) += coco/
> > +obj-y += coco/
> >   
> >   obj-y += entry/
> >   
> > diff --git a/arch/x86/coco/Makefile b/arch/x86/coco/Makefile
> > index c816acf78b6a..6aa52e719bf5 100644
> > --- a/arch/x86/coco/Makefile
> > +++ b/arch/x86/coco/Makefile
> > @@ -3,6 +3,6 @@ CFLAGS_REMOVE_core.o	= -pg
> >   KASAN_SANITIZE_core.o	:= n
> >   CFLAGS_core.o		+= -fno-stack-protector
> >   
> > -obj-y += core.o
> > +obj-$(CONFIG_ARCH_HAS_CC_PLATFORM) += core.o
> >   
> >   obj-$(CONFIG_INTEL_TDX_GUEST)	+= tdx/