Re: [RFC PATCH v6 01/26] Documentation/x86: Add CET description

Yu-cheng Yu
2018-11-20T20:36:38Z

On Tue, 2018-11-20 at 10:52 +0100, Ingo Molnar wrote:
> * Yu-cheng Yu <yu-cheng.yu@intel.com> wrote:
>
> > +X86 Documentation
> > [...]
> > +
> > +At run time, /proc/cpuinfo shows the availability of SHSTK and IBT.
>
> What is the rough expected performance impact of CET on average function
> call frequency user applications and the kernel itself?

I don't have any conclusive numbers yet; but since currently only user-mode
protection is implemented, I suspect any impact would be most likely to the
application. The kernel would spend some small amount of time on the setup of
CET.

Yu-cheng