From patchwork Sat May 16 08:53:54 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jarkko Sakkinen X-Patchwork-Id: 11553399 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C3B1290 for ; Sat, 16 May 2020 08:54:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AE80E20728 for ; Sat, 16 May 2020 08:54:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726202AbgEPIyg (ORCPT ); Sat, 16 May 2020 04:54:36 -0400 Received: from mga05.intel.com ([192.55.52.43]:44346 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725997AbgEPIyg (ORCPT ); Sat, 16 May 2020 04:54:36 -0400 IronPort-SDR: qDXY6qP8NcBnqrV8WcCkzRK5LPhDk+OGxUgJ/OeuVs0bW2GqYVc44HqcpnF+s6PcqewykNS1J9 xzJNw2aUEurg== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 May 2020 01:54:36 -0700 IronPort-SDR: wjifuI4z9WGGHb3jkaynPAj65Q0mtCCunn4F9mzGMUTtIB5HGUivSp5htRby1Lm61MkmnllhIt RgVomlJcqQOw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,398,1583222400"; d="scan'208";a="465009272" Received: from dbobocel-mobl1.ger.corp.intel.com (HELO localhost) ([10.252.55.115]) by fmsmga005.fm.intel.com with ESMTP; 16 May 2020 01:54:27 -0700 From: Jarkko Sakkinen To: linux-kernel@vger.kernel.org, x86@kernel.org, linux-sgx@vger.kernel.org Cc: Jarkko Sakkinen , Sean Christopherson , 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, josh@joshtriplett.org, 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 Subject: [PATCH] x86/cpu/intel: Add nosgx kernel parameter Date: Sat, 16 May 2020 11:53:54 +0300 Message-Id: <20200516085354.10478-1-jarkko.sakkinen@linux.intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200421215316.56503-1-jarkko.sakkinen@linux.intel.com> References: <20200421215316.56503-1-jarkko.sakkinen@linux.intel.com> MIME-Version: 1.0 Sender: linux-sgx-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org Add kernel parameter to disable Intel SGX kernel support. Tested-by: Sean Christopherson Reviewed-by: Sean Christopherson 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 7bc83f3d9bdf..9f7202a54db6 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -3268,6 +3268,8 @@ 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 c3afcd2e4342..1837df39527f 100644 --- a/arch/x86/kernel/cpu/feat_ctl.c +++ b/arch/x86/kernel/cpu/feat_ctl.c @@ -101,6 +101,15 @@ static void clear_sgx_caps(void) setup_clear_cpu_cap(X86_FEATURE_SGX2); } +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();