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=-7.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 43792C4360F for ; Fri, 5 Apr 2019 15:18:24 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 11491218D3 for ; Fri, 5 Apr 2019 15:18:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="ZJz+KgkI" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 11491218D3 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date: Message-ID:From:References:To:Subject:Reply-To:Content-ID:Content-Description :Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=sWz92U/bU9wjtLzKMwZ8/hO9uGJxI2EVsK7i6W+cELU=; b=ZJz+KgkI+UUDWP NSufxVucMMH46DWFBk0+eF3NVi9VdPU11e3YpeI/MBhuR/fAM7A1e1vHbkpfcGnVHz+yiZxtfwdVd OsHv3DQiV+trqvuLsgQvfDEIP2iOdJHe8dpVSDU7BwStQ9eBogbAnbJlRXzx8WtCtDJAijeaNUMy/ 1xWXwkNeV0ruK9kPOqjqnA3sutnuiAXwFlCflVz4myb2p1wvevHVqVOSh1Tpwuzl/nTRocZniNsnm 8atbnRXvZLkSzoqoN+sG0zZqVzF4meyrhBcYC5Mub16pU55b89ESkBpvO1fFN/2pxOy1t3N7iRybK +yxXi1TTqqNWxhNXDj/w==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hCQbh-00048x-62; Fri, 05 Apr 2019 15:18:17 +0000 Received: from static-50-53-52-16.bvtn.or.frontiernet.net ([50.53.52.16] helo=midway.dunlab) by bombadil.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1hCQbd-000474-IY; Fri, 05 Apr 2019 15:18:13 +0000 Subject: Re: [PATCH RFC 2/5] x86/speculation: Add support for 'cpu_spec_mitigations=' cmdline options To: Borislav Petkov , Josh Poimboeuf References: <78c63cb08f36f55407f534d49cc2543079e44dbb.1554396090.git.jpoimboe@redhat.com> <20190405135712.GF23348@zn.tnic> From: Randy Dunlap Message-ID: <5ccc7515-33e6-b726-833e-9553ab0f4c6a@infradead.org> Date: Fri, 5 Apr 2019 08:18:09 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.5.1 MIME-Version: 1.0 In-Reply-To: <20190405135712.GF23348@zn.tnic> Content-Language: en-US X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Peter Zijlstra , Benjamin Herrenschmidt , Heiko Carstens , Paul Mackerras , "H . Peter Anvin" , Ingo Molnar , Andrea Arcangeli , linux-s390@vger.kernel.org, Michael Ellerman , x86@kernel.org, Will Deacon , Linus Torvalds , Catalin Marinas , Waiman Long , linux-arch@vger.kernel.org, Jon Masters , Jiri Kosina , Andy Lutomirski , Thomas Gleixner , linux-arm-kernel@lists.infradead.org, Greg Kroah-Hartman , linux-kernel@vger.kernel.org, Tyler Hicks , Martin Schwidefsky , linuxppc-dev@lists.ozlabs.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 4/5/19 6:57 AM, Borislav Petkov wrote: > On Thu, Apr 04, 2019 at 11:44:12AM -0500, Josh Poimboeuf wrote: >> Configure x86 runtime CPU speculation bug mitigations in accordance with >> the 'cpu_spec_mitigations=' cmdline options. This affects Meltdown, >> Spectre v2, Speculative Store Bypass, and L1TF. >> >> The default behavior is unchanged. >> >> Signed-off-by: Josh Poimboeuf >> --- >> .../admin-guide/kernel-parameters.txt | 15 +++++++++ >> arch/x86/include/asm/processor.h | 1 + >> arch/x86/kernel/cpu/bugs.c | 32 ++++++++++++++++--- >> arch/x86/kvm/vmx/vmx.c | 2 ++ >> arch/x86/mm/pti.c | 4 ++- >> 5 files changed, 49 insertions(+), 5 deletions(-) >> >> diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt >> index ac42e510bd6e..29dc03971630 100644 >> --- a/Documentation/admin-guide/kernel-parameters.txt >> +++ b/Documentation/admin-guide/kernel-parameters.txt >> @@ -2552,6 +2552,11 @@ >> >> off >> Disable all speculative CPU mitigations. >> + Equivalent to: nopti [x86] >> + nospectre_v2 [x86] >> + spectre_v2_user=off [x86] >> + spec_store_bypass_disable=off [x86] >> + l1tf=off [x86] >> >> auto (default) >> Mitigate all speculative CPU vulnerabilities, >> @@ -2560,12 +2565,22 @@ >> surprised by SMT getting disabled across kernel >> upgrades, or who have other ways of avoiding >> SMT-based attacks. >> + Equivalent to: pti=auto [x86] >> + spectre_v2=auto [x86] >> + spectre_v2_user=auto [x86] >> + spec_store_bypass_disable=auto [x86] >> + l1tf=flush [x86] >> >> auto,nosmt >> Mitigate all speculative CPU vulnerabilities, >> disabling SMT if needed. This is for users who >> always want to be fully mitigated, even if it >> means losing SMT. >> + Equivalent to: pti=auto [x86] >> + spectre_v2=auto [x86] >> + spectre_v2_user=auto [x86] >> + spec_store_bypass_disable=auto [x86] >> + l1tf=flush,nosmt [x86] >> >> mminit_loglevel= >> [KNL] When CONFIG_DEBUG_MEMORY_INIT is set, this > > Yap, those sets look ok. nit: s/x86/X86/g according to Documentation/admin-guide/kernel-parameters.rst -- ~Randy _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel