From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 141C0C43441 for ; Sun, 25 Nov 2018 18:59:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DE83120868 for ; Sun, 25 Nov 2018 18:59:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DE83120868 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linutronix.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727658AbeKZFvS (ORCPT ); Mon, 26 Nov 2018 00:51:18 -0500 Received: from Galois.linutronix.de ([146.0.238.70]:52684 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725838AbeKZFsz (ORCPT ); Mon, 26 Nov 2018 00:48:55 -0500 Received: from localhost ([127.0.0.1] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtp (Exim 4.80) (envelope-from ) id 1gQzac-0003O2-OM; Sun, 25 Nov 2018 19:57:06 +0100 Message-Id: <20181125183328.318175777@linutronix.de> User-Agent: quilt/0.65 Date: Sun, 25 Nov 2018 19:33:28 +0100 From: Thomas Gleixner To: LKML Cc: x86@kernel.org, Peter Zijlstra , Andy Lutomirski , Linus Torvalds , Jiri Kosina , Tom Lendacky , Josh Poimboeuf , Andrea Arcangeli , David Woodhouse , Tim Chen , Andi Kleen , Dave Hansen , Casey Schaufler , Asit Mallick , Arjan van de Ven , Jon Masters , Waiman Long , Greg KH , Dave Stewart , Kees Cook Subject: [patch V2 00/28] x86/speculation: Remedy the STIBP/IBPB overhead Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Thats hopefully the final version of this. Changes since V1: - Renamed the command line option and related code to spectre_v2_user= as suggested by Josh. - Thought more about the back to back optimization and finally left the IBPB code in switch_mm(). It still removes the ptrace check for the always IBPB case. That's substantial overhead for dubious value now that the default is conditional (prctl/seccomp) IBPB. - Added two options which allow conditional STIBP and IBPB always mode. - Addressed the review comments Documentation is still work in progress. Thanks Andi for providing the first draft for it. Still based on tip.git x86/pti as it has been discussed to remove the minimal RETPOLINE bandaid from stable kernels as well. It's avaiable from git: git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git WIP.x86/pti Thanks, tglx 8<------------------------ Documentation/admin-guide/kernel-parameters.txt | 56 ++ Documentation/userspace-api/spec_ctrl.rst | 9 arch/x86/Kconfig | 8 arch/x86/include/asm/msr-index.h | 5 arch/x86/include/asm/nospec-branch.h | 14 arch/x86/include/asm/spec-ctrl.h | 18 arch/x86/include/asm/switch_to.h | 3 arch/x86/include/asm/thread_info.h | 18 arch/x86/include/asm/tlbflush.h | 8 arch/x86/kernel/cpu/bugs.c | 520 ++++++++++++++++++------ arch/x86/kernel/process.c | 79 ++- arch/x86/kernel/process.h | 39 + arch/x86/kernel/process_32.c | 10 arch/x86/kernel/process_64.c | 10 arch/x86/mm/tlb.c | 109 +++-- include/linux/ptrace.h | 17 include/linux/sched.h | 9 include/linux/sched/smt.h | 20 include/uapi/linux/prctl.h | 1 kernel/cpu.c | 15 kernel/ptrace.c | 10 kernel/sched/core.c | 19 kernel/sched/sched.h | 4 tools/include/uapi/linux/prctl.h | 1 24 files changed, 745 insertions(+), 257 deletions(-)