From patchwork Wed Nov 4 14:54:14 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jarkko Sakkinen X-Patchwork-Id: 11880843 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=-12.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 10582C388F9 for ; Wed, 4 Nov 2020 14:55:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BBE192236F for ; Wed, 4 Nov 2020 14:55:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730245AbgKDOz3 (ORCPT ); Wed, 4 Nov 2020 09:55:29 -0500 Received: from mail.kernel.org ([198.145.29.99]:49230 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730399AbgKDOz2 (ORCPT ); Wed, 4 Nov 2020 09:55:28 -0500 Received: from suppilovahvero.lan (83-245-197-237.elisa-laajakaista.fi [83.245.197.237]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 46FB521527; Wed, 4 Nov 2020 14:55:22 +0000 (UTC) From: Jarkko Sakkinen To: x86@kernel.org, linux-sgx@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Jarkko Sakkinen , Sean Christopherson , Darren Kenny , akpm@linux-foundation.org, andriy.shevchenko@linux.intel.com, asapek@google.com, bp@alien8.de, cedric.xing@intel.com, chenalexchen@google.com, conradparker@google.com, cyhanish@google.com, dave.hansen@intel.com, haitao.huang@intel.com, kai.huang@intel.com, kai.svahn@intel.com, kmoy@google.com, ludloff@google.com, luto@kernel.org, nhorman@redhat.com, npmccallum@redhat.com, puiterwijk@redhat.com, rientjes@google.com, tglx@linutronix.de, yaozhangx@google.com, mikko.ylinen@intel.com Subject: [PATCH v40 08/24] x86/cpu/intel: Add nosgx kernel parameter Date: Wed, 4 Nov 2020 16:54:14 +0200 Message-Id: <20201104145430.300542-9-jarkko.sakkinen@linux.intel.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20201104145430.300542-1-jarkko.sakkinen@linux.intel.com> References: <20201104145430.300542-1-jarkko.sakkinen@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org Add kernel parameter to disable Intel SGX kernel support, along with supporting Documentation. Tested-by: Sean Christopherson Reviewed-by: Sean Christopherson Reviewed-by: Darren Kenny Signed-off-by: Jarkko Sakkinen --- Documentation/admin-guide/kernel-parameters.txt | 2 ++ arch/x86/kernel/cpu/feat_ctl.c | 9 +++++++++ 2 files changed, 11 insertions(+) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index bd1a5b87a5e2..4684611edf09 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -3385,6 +3385,8 @@ nosep [BUGS=X86-32] Disables x86 SYSENTER/SYSEXIT support. + nosgx [X86-64,SGX] Disables Intel SGX kernel support. + nosmp [SMP] Tells an SMP kernel to act as a UP kernel, and disable the IO APIC. legacy for "maxcpus=0". diff --git a/arch/x86/kernel/cpu/feat_ctl.c b/arch/x86/kernel/cpu/feat_ctl.c index d38e97325018..3b1b01f2b248 100644 --- a/arch/x86/kernel/cpu/feat_ctl.c +++ b/arch/x86/kernel/cpu/feat_ctl.c @@ -99,6 +99,15 @@ static void clear_sgx_caps(void) setup_clear_cpu_cap(X86_FEATURE_SGX_LC); } +static int __init nosgx(char *str) +{ + clear_sgx_caps(); + + return 0; +} + +early_param("nosgx", nosgx); + void init_ia32_feat_ctl(struct cpuinfo_x86 *c) { bool tboot = tboot_enabled();