[MODERATED] Re: GPZv4

[Borislav Petkov <bp@suse.de>]

On Tue, Apr 17, 2018 at 05:03:01PM -0400, speck for Jon Masters wrote:
> [my one comment in this email on RHEL, feel free to skip next para]
> Red Hat's perspective is that we need to be "secure by default". I would
> /love/ to be able to leave MD enabled globally on all arches, but in
> order for that to happen, everyone across the industry would have to

I don't think you can do global decisions like that - it should be
per-vendor thing as everything else arch-specific is and we do what the
vendor suggests.

> So we need to close on the following urgently:
> 
> 1). What are we going to refer to this as?
> 	- MDD
> 	- SSB
> 	- something else?
> 
> In the case of "MDD" it's x86 specific and "enabling" it means you
> disable a feature (MD). To me, that seems to be inverted logic. You
> would set it to "on", "off", or "kernel" (MD only in userspace).
> 
> In the case of "SSB" it's more industry wide terminology but it's not
> the Intel term. You would set it to "on", "off", or "userspace".

I for one - and this is just me - see the point of calling it something
vendor- and arch-agnostic so sbb I guess. But whatever, as long as it is
only one name and the logic is spelled out somewhere.

> 2). We need a prctl option for a task to request behavior for SSB. One
> option could be a new PR_SET_MITIGATION where we then have minor
> parameters for additional mitigations that are required later.

I'd look towards other people here for ideas. But prctl() sounds simple
enough to me.

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
--