Re: [PATCH, RFC 57/62] x86/mktme: Overview of Multi-Key Total Memory Encryption

From: Kirill A. Shutemov
Date: Mon Jul 15 2019 - 05:02:55 EST


On Sun, Jul 14, 2019 at 06:16:49PM +0000, Randy Dunlap wrote:
> On 5/8/19 7:44 AM, Kirill A. Shutemov wrote:
> > From: Alison Schofield <alison.schofield@xxxxxxxxx>
> >
> > Provide an overview of MKTME on Intel Platforms.
> >
> > Signed-off-by: Alison Schofield <alison.schofield@xxxxxxxxx>
> > Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
> > ---
> > Documentation/x86/mktme/index.rst | 8 +++
> > Documentation/x86/mktme/mktme_overview.rst | 57 ++++++++++++++++++++++
> > 2 files changed, 65 insertions(+)
> > create mode 100644 Documentation/x86/mktme/index.rst
> > create mode 100644 Documentation/x86/mktme/mktme_overview.rst
>
>
> > diff --git a/Documentation/x86/mktme/mktme_overview.rst b/Documentation/x86/mktme/mktme_overview.rst
> > new file mode 100644
> > index 000000000000..59c023965554
> > --- /dev/null
> > +++ b/Documentation/x86/mktme/mktme_overview.rst
> > @@ -0,0 +1,57 @@
> > +Overview
> > +=========
> ...
> > +--
> > +1. https://software.intel.com/sites/default/files/managed/a5/16/Multi-Key-Total-Memory-Encryption-Spec.pdf
> > +2. The MKTME architecture supports up to 16 bits of KeyIDs, so a
> > + maximum of 65535 keys on top of the âTME keyâ at KeyID-0. The
> > + first implementation is expected to support 5 bits, making 63
>
> Hi,
> How do 5 bits make 63 keys available?

Yep, typo. It has to be 6 bits.

Alison, please correct this.

--
Kirill A. Shutemov