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=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 AD7D2C2B9F4 for ; Tue, 22 Jun 2021 18:56:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 90ABE61166 for ; Tue, 22 Jun 2021 18:56:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232629AbhFVS6t (ORCPT ); Tue, 22 Jun 2021 14:58:49 -0400 Received: from mga01.intel.com ([192.55.52.88]:50414 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230146AbhFVS6s (ORCPT ); Tue, 22 Jun 2021 14:58:48 -0400 IronPort-SDR: +HPSTLvYc+ib9cucg8igwtI+0opHBez6/eiotZZ0ss0Blxksu0LWmXEhNsDvg/AM4wOVpB5U61 7JXUbvNc1xvg== X-IronPort-AV: E=McAfee;i="6200,9189,10023"; a="228680950" X-IronPort-AV: E=Sophos;i="5.83,292,1616482800"; d="scan'208";a="228680950" Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Jun 2021 11:56:32 -0700 IronPort-SDR: hEhYUuZ3uflNZGVhO8COvCa5nt9rhyBUml8ltHiOsVRWrFwErddQ6j/elc5QSOl7coyQdssxfP pR2Zmg/LKxfw== X-IronPort-AV: E=Sophos;i="5.83,292,1616482800"; d="scan'208";a="444703154" Received: from meghadey-mobl1.amr.corp.intel.com (HELO [10.251.74.37]) ([10.251.74.37]) by orsmga007-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Jun 2021 11:56:29 -0700 Subject: Re: [patch V3 00/66] x86/fpu: Spring cleaning and PKRU sanitizing To: Thomas Gleixner , LKML Cc: Andy Lutomirski , Dave Hansen , Fenghua Yu , Tony Luck , Yu-cheng Yu , Sebastian Andrzej Siewior , Borislav Petkov , Peter Zijlstra , Kan Liang References: <20210618141823.161158090@linutronix.de> From: "Dey, Megha" Message-ID: Date: Wed, 23 Jun 2021 00:26:14 +0530 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <20210618141823.161158090@linutronix.de> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Thomas, On 6/18/2021 7:48 PM, Thomas Gleixner wrote: > The main parts of this series are: > > - Yet more bug fixes > > - Simplification and removal/replacement of redundant and/or > overengineered code. > > - Name space cleanup as the existing names were just a permanent source > of confusion. > > - Clear seperation of user ABI and kernel internal state handling. > > - Removal of PKRU from being XSTATE managed in the kernel because PKRU > has to be eagerly restored on context switch and keeping it in sync > in the xstate buffer is just pointless overhead and fragile. > > The kernel still XSAVEs PKRU on context switch but the value in the > buffer is not longer used and never restored from the buffer. > > This still needs to be cleaned up, but the series is already 40+ > patches large and the cleanup of this is not a functional problem. > > The functional issues of PKRU management are fully addressed with the > series as is. > > - Cleanup of fpu signal restore > > - Make the fast path self contained. Handle #PF directly and skip > the slow path on any other exception as that will just end up > with the same result that the frame is invalid. This allows > the compiler to optimize the slow path out for 64bit kernels > w/o ia32 emulation. > > - Reduce code duplication and unnecessary operations > > > It applies on top of > > git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git master > > and is also available via git: > > git://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git x86/fpu > > This is a follow up to V2 which can be found here: > > https://lore.kernel.org/r/20210614154408.673478623@linutronix.de I tested the x86/fpu branch using both AVX2(intree) and AVX512(out of tree) crypto code. I used the tcrypt test module in the kernel and ran the prime95 workload (which finds prime numbers using AVX2 or AVX512) as a background process to make sure that the AVX states don't get screwed up after we run the crypto in kernel. I did not see any issues with this branch and all tcrypt tests run as expected. I tested using the SHA1/256, AES-CTR, AES-GCM, camelia and crc32t10diff crypto algorithms. Thanks, Megha > > Changes vs. V2: > > - Fixed the testing fallout (Dave, Kan) > > - Fixed a few issues found by myself when going through the lot > with a fine comb, especially MXCSR handling > > - Drop the FNSAVE optimizations > > - Cleanup of signal restore > > - Addressed review comments, mostly comments and a hopefully better > naming scheme which now just uses the instruction names and > consolidates everything else on save/restore so it's close to the way > how the hardware works. > > - A few cleanups and simplifications on the way (mostly regset related). > > - Picked up tags > > With the above I'm not intending to do any further surgery on that > code at the moment, though there is still room for improvement which > can and has to be worked on when new bits are added. > > Thanks, > > tglx > --- > arch/x86/events/intel/lbr.c | 6 > arch/x86/include/asm/fpu/internal.h | 211 +++------- > arch/x86/include/asm/fpu/xstate.h | 70 ++- > arch/x86/include/asm/pgtable.h | 57 -- > arch/x86/include/asm/pkeys.h | 9 > arch/x86/include/asm/pkru.h | 62 +++ > arch/x86/include/asm/processor.h | 9 > arch/x86/include/asm/special_insns.h | 14 > arch/x86/kernel/cpu/common.c | 34 - > arch/x86/kernel/fpu/core.c | 276 +++++++------ > arch/x86/kernel/fpu/init.c | 15 > arch/x86/kernel/fpu/regset.c | 220 ++++++----- > arch/x86/kernel/fpu/signal.c | 423 +++++++++------------ > arch/x86/kernel/fpu/xstate.c | 693 ++++++++++++++--------------------- > arch/x86/kernel/process.c | 22 - > arch/x86/kernel/process_64.c | 28 + > arch/x86/kernel/traps.c | 5 > arch/x86/kvm/svm/sev.c | 1 > arch/x86/kvm/x86.c | 56 +- > arch/x86/mm/extable.c | 2 > arch/x86/mm/fault.c | 2 > arch/x86/mm/pkeys.c | 22 - > include/linux/pkeys.h | 4 > 23 files changed, 1060 insertions(+), 1181 deletions(-) > >