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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 1C8FBC33CAF for ; Thu, 16 Jan 2020 03:51:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E3C1C207E0 for ; Thu, 16 Jan 2020 03:51:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730342AbgAPDvb (ORCPT ); Wed, 15 Jan 2020 22:51:31 -0500 Received: from ZXSHCAS2.zhaoxin.com ([203.148.12.82]:26363 "EHLO ZXSHCAS2.zhaoxin.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1728925AbgAPDva (ORCPT ); Wed, 15 Jan 2020 22:51:30 -0500 Received: from zxbjmbx1.zhaoxin.com (10.29.252.163) by ZXSHCAS2.zhaoxin.com (10.28.252.162) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1261.35; Thu, 16 Jan 2020 11:51:28 +0800 Received: from [10.32.64.11] (10.32.64.11) by zxbjmbx1.zhaoxin.com (10.29.252.163) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1261.35; Thu, 16 Jan 2020 11:51:27 +0800 Subject: Re: [PATCH] x86/cpu: clear X86_BUG_SPECTRE_V2 on Zhaoxin family 7 CPUs To: Thomas Gleixner , , , , , CC: , , , References: <1579075500-7065-1-git-send-email-TonyWWang-oc@zhaoxin.com> <87h80wxsze.fsf@nanos.tec.linutronix.de> From: Tony W Wang-oc Message-ID: Date: Thu, 16 Jan 2020 11:51:39 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <87h80wxsze.fsf@nanos.tec.linutronix.de> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.32.64.11] X-ClientProxiedBy: zxbjmbx1.zhaoxin.com (10.29.252.163) To zxbjmbx1.zhaoxin.com (10.29.252.163) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 16/01/2020 06:19, Thomas Gleixner wrote: > Tony W Wang-oc writes: > >> These CPUs are not affected by spectre_v2, so clear spectre_v2 bug flag >> in their specific initialization code. >> >> if (cpu_has(c, X86_FEATURE_VMX)) >> centaur_detect_vmx_virtcap(c); >> + >> + if (c->x86 == 7) { >> + setup_clear_cpu_cap(X86_BUG_SPECTRE_V2); >> + clear_bit(X86_BUG_SPECTRE_V2, (unsigned long *)cpu_caps_set); > > No. Please use cpu_vuln_whitelist. It exists for exactly this > purpose. You just need to extend it with a NO_SPECTRE_V2 bit. Got, done. Sincerely TonyWWang-oc