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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,USER_AGENT_GIT autolearn=no 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 A730DC433DF for ; Tue, 26 May 2020 04:35:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9022D207ED for ; Tue, 26 May 2020 04:35:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725775AbgEZEfV (ORCPT ); Tue, 26 May 2020 00:35:21 -0400 Received: from out30-131.freemail.mail.aliyun.com ([115.124.30.131]:36090 "EHLO out30-131.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725891AbgEZEfR (ORCPT ); Tue, 26 May 2020 00:35:17 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R911e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04357;MF=laijs@linux.alibaba.com;NM=1;PH=DS;RN=6;SR=0;TI=SMTPD_---0TzgjMIS_1590467711; Received: from localhost(mailfrom:laijs@linux.alibaba.com fp:SMTPD_---0TzgjMIS_1590467711) by smtp.aliyun-inc.com(127.0.0.1); Tue, 26 May 2020 12:35:12 +0800 From: Lai Jiangshan To: linux-kernel@vger.kernel.org Cc: Lai Jiangshan , Andy Lutomirski , Peter Zijlstra , Thomas Gleixner , x86@kernel.org Subject: [PATCH 0/2] x86/entry: simplify RESTORE_CR3 Date: Tue, 26 May 2020 04:35:05 +0000 Message-Id: <20200526043507.51977-1-laijs@linux.alibaba.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When I searched percpu data touched by entry code for #DB protection[1], it seems to me RESTORE_CR3() does too much work, this patchset simplifies it. Patch 1 enhances 21e944591102("x86/mm: Optimize RESTORE_CR3") for kernel CR3. Patch 2 *reverts* 21e944591102("x86/mm: Optimize RESTORE_CR3") for User CR3. Cc: Andy Lutomirski Cc: Peter Zijlstra (Intel) Cc: Thomas Gleixner Cc: x86@kernel.org Link: https://lore.kernel.org/lkml/20200525145102.122557-1-laijs@linux.alibaba.com Lai Jiangshan (2): x86/entry: Don't write to CR3 when restoring to kernel CR3 x86/entry: always flush user CR3 in RESTORE_CR3 arch/x86/entry/calling.h | 36 ++++++++---------------------------- arch/x86/entry/entry_64.S | 6 +++--- 2 files changed, 11 insertions(+), 31 deletions(-) -- 2.20.1