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,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 D73BCC43215 for ; Wed, 20 Nov 2019 15:40:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AB53920709 for ; Wed, 20 Nov 2019 15:40:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729659AbfKTPkP (ORCPT ); Wed, 20 Nov 2019 10:40:15 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:52506 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729401AbfKTPkO (ORCPT ); Wed, 20 Nov 2019 10:40:14 -0500 Received: from [167.98.27.226] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1iXS5T-0004Yy-9V; Wed, 20 Nov 2019 15:40:11 +0000 Received: from ben by deadeye with local (Exim 4.93-RC1) (envelope-from ) id 1iXS5S-0004G4-NF; Wed, 20 Nov 2019 15:40:10 +0000 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Denis Kirjanov , "Zhenzhong Duan" , "Thomas Gleixner" Date: Wed, 20 Nov 2019 15:37:18 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 08/83] x86/speculation/mds: Apply more accurate check on hypervisor platform In-Reply-To: X-SA-Exim-Connect-IP: 167.98.27.226 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.78-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Zhenzhong Duan commit 517c3ba00916383af6411aec99442c307c23f684 upstream. X86_HYPER_NATIVE isn't accurate for checking if running on native platform, e.g. CONFIG_HYPERVISOR_GUEST isn't set or "nopv" is enabled. Checking the CPU feature bit X86_FEATURE_HYPERVISOR to determine if it's running on native platform is more accurate. This still doesn't cover the platforms on which X86_FEATURE_HYPERVISOR is unsupported, e.g. VMware, but there is nothing which can be done about this scenario. Fixes: 8a4b06d391b0 ("x86/speculation/mds: Add sysfs reporting for MDS") Signed-off-by: Zhenzhong Duan Signed-off-by: Thomas Gleixner Link: https://lkml.kernel.org/r/1564022349-17338-1-git-send-email-zhenzhong.duan@oracle.com [bwh: Backported to 3.16: The old hypervisor check looked a bit different here.] Signed-off-by: Ben Hutchings --- --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -1349,12 +1349,10 @@ static ssize_t itlb_multihit_show_state( static ssize_t mds_show_state(char *buf) { -#ifdef CONFIG_HYPERVISOR_GUEST - if (x86_hyper) { + if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) { return sprintf(buf, "%s; SMT Host state unknown\n", mds_strings[mds_mitigation]); } -#endif if (boot_cpu_has(X86_BUG_MSBDS_ONLY)) { return sprintf(buf, "%s; SMT %s\n", mds_strings[mds_mitigation],