Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752248AbdGaOQg (ORCPT ); Mon, 31 Jul 2017 10:16:36 -0400 Received: from mail.kernel.org ([198.145.29.99]:54930 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750987AbdGaOQf (ORCPT ); Mon, 31 Jul 2017 10:16:35 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A4AAA22C92 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=luto@kernel.org MIME-Version: 1.0 In-Reply-To: <20170731105540.tovjhththy2u2dtb@node.shutemov.name> References: <20170731105540.tovjhththy2u2dtb@node.shutemov.name> From: Andy Lutomirski Date: Mon, 31 Jul 2017 07:16:13 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: FSGSBASE ABI considerations To: "Kirill A. Shutemov" Cc: Andy Lutomirski , "Bae, Chang Seok" , X86 ML , "linux-kernel@vger.kernel.org" , Linus Torvalds , Borislav Petkov , Brian Gerst , Stas Sergeev Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 788 Lines: 20 On Mon, Jul 31, 2017 at 3:55 AM, Kirill A. Shutemov wrote: > On Sun, Jul 30, 2017 at 08:05:43PM -0700, Andy Lutomirski wrote: >> Hi all- >> >> Chang wants to get the FSGSBASE patches in. Here's a bit on a brain >> dump on what I think the relevant considerations are and why I haven't >> sent out my patches. > > I'm not sure if it would be relevant input for the descussion, but there's > another issue with FSGSBASE vs LA57: > > http://lkml.kernel.org/r/9ddf602b-6c8b-8c1e-ab46-07ed12366593@redhat.com Clearly we should support FSGSBASE on Linux, have Paolo blacklist it on LA57 machines, and get Java to start using it just to pressure Intel to clean up this mess. Sigh, the degree to which CPU engineers don't understand software is sometimes mind-boggling.