Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932913AbdC2VlP (ORCPT ); Wed, 29 Mar 2017 17:41:15 -0400 Received: from mail-it0-f66.google.com ([209.85.214.66]:34136 "EHLO mail-it0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754287AbdC2VlB (ORCPT ); Wed, 29 Mar 2017 17:41:01 -0400 MIME-Version: 1.0 In-Reply-To: References: <20170329203908.GA39222@beast> From: Linus Torvalds Date: Wed, 29 Mar 2017 14:41:00 -0700 X-Google-Sender-Auth: xsk79wgv0qNe58hE0aJPwm9YTDI Message-ID: Subject: Re: [PATCH] x86/fpu: move FPU state into separate cache To: Andy Lutomirski Cc: Kees Cook , "H. Peter Anvin" , LKML , Rik van Riel , Andy Lutomirski , Thomas Gleixner , Ingo Molnar , "x86@kernel.org" , Paolo Bonzini , =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , Peter Zijlstra , Dave Hansen , Yu-cheng Yu , Masahiro Yamada , Borislav Petkov , Christian Borntraeger , Thomas Garnier , Brian Gerst , He Chen , Mathias Krause , Fenghua Yu , Piotr Luc , Kyle Huey , Len Brown , KVM , "kernel-hardening@lists.openwall.com" 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: 478 Lines: 12 On Wed, Mar 29, 2017 at 2:35 PM, Andy Lutomirski wrote: > > Randomization also needs to leave thread_info at the beginning. Can it do that? Good point, and good question. No idea if the gcc extension can do, but yes, it clearly needs a "you can't move this entry". I assume it has some such capability already, because it's fairly common to have that kind of "beginning of structure if fixed" due to unions of structures anyway. Linus