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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <16a0261fbe4b31e2f42b552d6a991a1116d398c2.camel@intel.com>
Date:   Tue, 20 Nov 2018 12:36:38 -0800
From:   Yu-cheng Yu <yu-cheng.yu@...el.com>
To:     Ingo Molnar <mingo@...nel.org>
Cc:     x86@...nel.org, "H. Peter Anvin" <hpa@...or.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>, linux-kernel@...r.kernel.org,
        linux-doc@...r.kernel.org, linux-mm@...ck.org,
        linux-arch@...r.kernel.org, linux-api@...r.kernel.org,
        Arnd Bergmann <arnd@...db.de>,
        Andy Lutomirski <luto@...capital.net>,
        Balbir Singh <bsingharora@...il.com>,
        Cyrill Gorcunov <gorcunov@...il.com>,
        Dave Hansen <dave.hansen@...ux.intel.com>,
        Eugene Syromiatnikov <esyr@...hat.com>,
        Florian Weimer <fweimer@...hat.com>,
        "H.J. Lu" <hjl.tools@...il.com>, Jann Horn <jannh@...gle.com>,
        Jonathan Corbet <corbet@....net>,
        Kees Cook <keescook@...omium.org>,
        Mike Kravetz <mike.kravetz@...cle.com>,
        Nadav Amit <nadav.amit@...il.com>,
        Oleg Nesterov <oleg@...hat.com>, Pavel Machek <pavel@....cz>,
        Peter Zijlstra <peterz@...radead.org>,
        Randy Dunlap <rdunlap@...radead.org>,
        "Ravi V. Shankar" <ravi.v.shankar@...el.com>,
        Vedvyas Shanbhogue <vedvyas.shanbhogue@...el.com>
Subject: Re: [RFC PATCH v6 01/26] Documentation/x86: Add CET description

On Tue, 2018-11-20 at 10:52 +0100, Ingo Molnar wrote:
> * Yu-cheng Yu <yu-cheng.yu@...el.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