Re: [RFC 09/10] x86/enter: Create macros to restrict/unrestrict Indirect Branch Speculation

[Linus Torvalds]

On Fri, Jan 26, 2018 at 1:11 AM, David Woodhouse <dwmw2@xxxxxxxxxxxxx> wrote:
>
> Do we need to look again at the fact that we've disabled the RSB-
> stuffing for SMEP?

Absolutely. SMEP helps make people a lot less worried about things,
but it doesn't fix the "BTB only contains partial addresses" case.

But did we do that "disable stuffing with SMEP"? I'm not seeing it. In
my tree, it's only conditional on X86_FEATURE_RETPOLINE.

                   Linus