From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alan Cox <alan@linux.intel.com>
Subject: Re: [PATCH bpf] bpf: prevent out-of-bounds speculation
Date: Wed, 17 Jan 2018 14:47:50 +0000
Message-ID: <1516200470.4184.26.camel@linux.intel.com>
References: <20180105042811.1590965-1-ast@fb.com>
         <20180108170553.yrs46fawfpr62wtr@lakrids.cambridge.arm.com>
         <CA+55aFz0tsreoa=5Ud2noFCpng-dizLBhT9WU9asyhpLfjdcYA@mail.gmail.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 7bit
Cc: Alexei Starovoitov <ast@fb.com>,
        "David S . Miller" <davem@davemloft.net>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Jann Horn <jannh@google.com>,
        Dan Williams <dan.j.williams@intel.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Elena Reshetova <elena.reshetova@intel.com>,
        Network Development <netdev@vger.kernel.org>,
        kernel-team <kernel-team@fb.com>,
        Will Deacon <will.deacon@arm.com>
To: Linus Torvalds <torvalds@linux-foundation.org>,
        Mark Rutland <mark.rutland@arm.com>
Return-path: <netdev-owner@vger.kernel.org>
Received: from mga14.intel.com ([192.55.52.115]:57595 "EHLO mga14.intel.com"
        rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
        id S1753168AbeAQOsT (ORCPT <rfc822;netdev@vger.kernel.org>);
        Wed, 17 Jan 2018 09:48:19 -0500
In-Reply-To: <CA+55aFz0tsreoa=5Ud2noFCpng-dizLBhT9WU9asyhpLfjdcYA@mail.gmail.com>
Sender: netdev-owner@vger.kernel.org
List-ID: <netdev.vger.kernel.org>

>  (c) isn't actually done in any real CPU's today that I'm aware of
> (unless you want to call the return stack data speculation).

There are processors out there today that data speculate.

For Intel family 6 Core, Knights and Atom today all is good.

Alan