Re: [RFC PATCH v4 07/28] x86: Provide general kernel support for memory encryption

[Tom Lendacky]

On 2/20/2017 12:38 PM, Borislav Petkov wrote:
> On Thu, Feb 16, 2017 at 09:43:32AM -0600, Tom Lendacky wrote:
> > Adding general kernel support for memory encryption includes:
> > - Modify and create some page table macros to include the Secure Memory
> >   Encryption (SME) memory encryption mask
> > - Modify and create some macros for calculating physical and virtual
> >   memory addresses
> > - Provide an SME initialization routine to update the protection map with
> >   the memory encryption mask so that it is used by default
> > - #undef CONFIG_AMD_MEM_ENCRYPT in the compressed boot path
> >
> > Signed-off-by: Tom Lendacky <thomas.lendacky@xxxxxxx>
>
> ...
>
> > +#define __sme_pa(x)		(__pa((x)) | sme_me_mask)
> > +#define __sme_pa_nodebug(x)	(__pa_nodebug((x)) | sme_me_mask)
> > +
> >  #else	/* !CONFIG_AMD_MEM_ENCRYPT */
> >
> >  #ifndef sme_me_mask
> > @@ -35,6 +42,13 @@ static inline bool sme_active(void)
> >  }
> >  #endif
> >
> > +static inline void __init sme_early_init(void)
> > +{
> > +}
> > +
> > +#define __sme_pa		__pa
> > +#define __sme_pa_nodebug	__pa_nodebug
>
> One more thing - in the !CONFIG_AMD_MEM_ENCRYPT case, sme_me_mask is 0
> so you don't need to define __sme_pa* again.

Makes sense.  I'll move those macros outside the #ifdef (I'll do the
same for the new __sme_clr() and __sme_set() macros, too).

Thanks,
Tom

>