Re: [PATCH v3 5/5] sev/i386: Enable an SEV-ES guest based on SEV policy

[Tom Lendacky]

On 9/17/20 11:07 AM, Tom Lendacky wrote:
> On 9/17/20 10:34 AM, Dr. David Alan Gilbert wrote:
> > * Tom Lendacky (thomas.lendacky@amd.com) wrote:
> > > From: Tom Lendacky <thomas.lendacky@amd.com>
> > >
> > > Update the sev_es_enabled() function return value to be based on the SEV
> > > policy that has been specified. SEV-ES is enabled if SEV is enabled and
> > > the SEV-ES policy bit is set in the policy object.
> > >
> > > Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
> > > ---
> > >   target/i386/sev.c | 4 +++-
> > >   1 file changed, 3 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/target/i386/sev.c b/target/i386/sev.c
> > > index 6ddefc65fa..bcaadaa2f9 100644
> > > --- a/target/i386/sev.c
> > > +++ b/target/i386/sev.c
> > > @@ -70,6 +70,8 @@ struct SevGuestState {
> > >   #define DEFAULT_GUEST_POLICY    0x1 /* disable debug */
> > >   #define DEFAULT_SEV_DEVICE      "/dev/sev"
> > > +#define GUEST_POLICY_SEV_ES_BIT (1 << 2)
> > > +
> >
> > I'm surprised that all the policy bits aren't defined in a header 
> > somewhere.
>
> I have another version to be issued with changes to use QemuUUID, so I can 
> look at moving the bits to a header.

Hmmm... and they already are defined in target/i386/sev_i386.h. I guess I 
was looking for sev.h and didn't notice sev_i386.h. So I'll update to use 
the values in sev_i386.h.

Thanks,
Tom

> Thanks,
> Tom
>
> > But other than that,
> >
> >
> > Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
> >
> > >   /* SEV Information Block GUID = 00f771de-1a7e-4fcb-890e-68c77e2fb44e */
> > >   #define SEV_INFO_BLOCK_GUID \
> > >       "\xde\x71\xf7\x00\x7e\x1a\xcb\x4f\x89\x0e\x68\xc7\x7e\x2f\xb4\x4e"
> > > @@ -375,7 +377,7 @@ sev_enabled(void)
> > >   bool
> > >   sev_es_enabled(void)
> > >   {
> > > -    return false;
> > > +    return sev_enabled() && (sev_guest->policy & 
> > > GUEST_POLICY_SEV_ES_BIT);
> > >   }
> > >   uint64_t
> > > --
> > > 2.28.0