From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758055AbcDHKkq (ORCPT ); Fri, 8 Apr 2016 06:40:46 -0400 Received: from mail.skyhub.de ([78.46.96.112]:57583 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757550AbcDHKko (ORCPT ); Fri, 8 Apr 2016 06:40:44 -0400 Date: Fri, 8 Apr 2016 12:40:40 +0200 From: Borislav Petkov To: Andy Lutomirski Cc: security@kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org, Linus Torvalds , Rudolf Marek Subject: Re: [PATCH v3 0/7] x86: Pile o' FS/GS changes Message-ID: <20160408104039.GF29522@pd.tnic> References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Apr 07, 2016 at 05:31:43PM -0700, Andy Lutomirski wrote: > Hi all- > > This whole mess is intended for x86/urgent. It fixes several bugs. > > It's probably a tiny performance regression on some workloads on > Intel CPUs. It's probably varies between a less tiny regression and > a small speedup on newer AMD CPUs. It's a bigger regression on AMD > K8. > > The AMD code could be further sped up by adding a new 'clear_gs' > pvop with a better native implementation. I don't particularly want > to deal with a backported new pvop, so I didn't do that. Maybe I'll > do it later on for new kernels, though. > > (For people who care about such things, there are probably three > bugs in here depending how you count. Somewhere between one and two > of them were independently discovered by Rudolf Marek.) > > Andy Lutomirski (5): > selftests/x86: Test the FSBASE/GSBASE API and context switching > x86/arch_prctl: Fix ARCH_GET_FS and ARCH_GET_GS > x86/cpu: Probe the behavior of nulling out a segment at boot time > x86/switch_to: Rewrite the FS and GS context switch code > x86/cpu: Move X86_BUG_ESPFIX initialization to generic_identify > > Borislav Petkov (2): > x86/cpu: Add Erratum 88 detection on AMD > x86/entry: Make gs_change a local label > > arch/x86/entry/entry_64.S | 12 +- > arch/x86/include/asm/cpufeatures.h | 3 + > arch/x86/kernel/cpu/amd.c | 1 + > arch/x86/kernel/cpu/common.c | 71 ++++-- > arch/x86/kernel/process_64.c | 167 ++++++++------ > tools/testing/selftests/x86/Makefile | 1 + > tools/testing/selftests/x86/fsgsbase.c | 398 +++++++++++++++++++++++++++++++++ > 7 files changed, 560 insertions(+), 93 deletions(-) > create mode 100644 tools/testing/selftests/x86/fsgsbase.c Forgot to add: Reviewed-by: Borislav Petkov -- Regards/Gruss, Boris. ECO tip #101: Trim your mails when you reply.