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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 BF7E5C43441 for ; Sun, 11 Nov 2018 19:59:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 896A5214E0 for ; Sun, 11 Nov 2018 19:59:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 896A5214E0 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=decadent.org.uk Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730948AbeKLFs6 (ORCPT ); Mon, 12 Nov 2018 00:48:58 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:51416 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730900AbeKLFsk (ORCPT ); Mon, 12 Nov 2018 00:48:40 -0500 Received: from [192.168.4.242] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1gLvst-0000oF-Gl; Sun, 11 Nov 2018 19:59:03 +0000 Received: from ben by deadeye with local (Exim 4.91) (envelope-from ) id 1gLvsV-0001fU-Bc; Sun, 11 Nov 2018 19:58:39 +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, andrew.cooper3@citrix.com, "H. Peter Anvin" , "David Woodhouse" , "Kees Cook" , "Konrad Rzeszutek Wilk" , "Borislav Petkov" , "KarimAllah Ahmed" , kvm@vger.kernel.org, "Thomas Gleixner" Date: Sun, 11 Nov 2018 19:49:05 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 222/366] x86/bugs: Switch the selection of mitigation from CPU vendor to CPU features In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.242 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 3.16.61-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Konrad Rzeszutek Wilk commit 108fab4b5c8f12064ef86e02cb0459992affb30f upstream. Both AMD and Intel can have SPEC_CTRL_MSR for SSBD. However AMD also has two more other ways of doing it - which are !SPEC_CTRL MSR ways. Signed-off-by: Konrad Rzeszutek Wilk Signed-off-by: Thomas Gleixner Cc: Kees Cook Cc: kvm@vger.kernel.org Cc: KarimAllah Ahmed Cc: andrew.cooper3@citrix.com Cc: "H. Peter Anvin" Cc: Borislav Petkov Cc: David Woodhouse Link: https://lkml.kernel.org/r/20180601145921.9500-4-konrad.wilk@oracle.com Signed-off-by: Ben Hutchings --- arch/x86/kernel/cpu/bugs.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -573,17 +573,12 @@ static enum ssb_mitigation __init __ssb_ * Intel uses the SPEC CTRL MSR Bit(2) for this, while AMD may * use a completely different MSR and bit dependent on family. */ - switch (boot_cpu_data.x86_vendor) { - case X86_VENDOR_INTEL: - case X86_VENDOR_AMD: - if (!static_cpu_has(X86_FEATURE_MSR_SPEC_CTRL)) { - x86_amd_ssb_disable(); - break; - } + if (!static_cpu_has(X86_FEATURE_MSR_SPEC_CTRL)) + x86_amd_ssb_disable(); + else { x86_spec_ctrl_base |= SPEC_CTRL_SSBD; x86_spec_ctrl_mask |= SPEC_CTRL_SSBD; wrmsrl(MSR_IA32_SPEC_CTRL, x86_spec_ctrl_base); - break; } }