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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 10982C433EF for ; Sun, 13 Mar 2022 10:52:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234416AbiCMKxP (ORCPT ); Sun, 13 Mar 2022 06:53:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43736 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234429AbiCMKwx (ORCPT ); Sun, 13 Mar 2022 06:52:53 -0400 Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A829E4AE1F; Sun, 13 Mar 2022 03:51:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1647168686; x=1678704686; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=9l+LPMkLtqeMSWP1b4SOmyqedQ8aVLN9kIwR5ZjsVQI=; b=FPIY3K61Wm18luhGAlMcGtML5U1+CJz/pJI+pPfM1iaov/ABZwJ4Wd5D FzJ6SLL1ejjxNAWRa3ZLQb2TdrPm9NlqxS9cxf/6+7bOyy47Fb8jQJ5oI uUOAPVhZvZbFMYorxjOI4o1Z6BxqNC3GXW9eowZVudogx9hr7zwHc/Nsq XFK6waO/bUo3AksjjSGbRp2BJj1tL118fHWsLZvoiQxvQxIGp3yUTLwms ItjT77AN5MHcgIvCoqjzMAb02XbjIyC3/lP3/8s7G24Rk2Qnulod25KZo X0xwan0a4hDMEjwV+wcoM+oRQ5BYSz8blTzzc7MMTbuMH04KnGRkgRr2v Q==; X-IronPort-AV: E=McAfee;i="6200,9189,10284"; a="255590723" X-IronPort-AV: E=Sophos;i="5.90,178,1643702400"; d="scan'208";a="255590723" Received: from orsmga004.jf.intel.com ([10.7.209.38]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Mar 2022 03:51:15 -0700 X-IronPort-AV: E=Sophos;i="5.90,178,1643702400"; d="scan'208";a="645448251" Received: from mvideche-mobl1.amr.corp.intel.com (HELO khuang2-desk.gar.corp.intel.com) ([10.251.130.249]) by orsmga004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Mar 2022 03:51:12 -0700 From: Kai Huang To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: dave.hansen@intel.com, seanjc@google.com, pbonzini@redhat.com, kirill.shutemov@linux.intel.com, sathyanarayanan.kuppuswamy@linux.intel.com, peterz@infradead.org, tony.luck@intel.com, ak@linux.intel.com, dan.j.williams@intel.com, isaku.yamahata@intel.com, kai.huang@intel.com Subject: [PATCH v2 20/21] x86/virt/tdx: Add kernel command line to opt-in TDX host support Date: Sun, 13 Mar 2022 23:50:00 +1300 Message-Id: <97c3539843a2c9cfdfd4a4ba2786be9b76afdd78.1647167475.git.kai.huang@intel.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Enabling TDX consumes additional memory (used by TDX as metadata) and additional initialization time. Introduce a kernel command line to allow to opt-in TDX host kernel support when user truly wants to use TDX. Signed-off-by: Kai Huang --- Documentation/admin-guide/kernel-parameters.txt | 6 ++++++ arch/x86/virt/vmx/tdx.c | 14 ++++++++++++++ 2 files changed, 20 insertions(+) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index f5a27f067db9..9f85cafd0c2d 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -5707,6 +5707,12 @@ tdfx= [HW,DRM] + tdx_host= [X86-64, TDX] + Format: {on|off} + on: Enable TDX host kernel support + off: Disable TDX host kernel support + Default is off. + test_suspend= [SUSPEND][,N] Specify "mem" (for Suspend-to-RAM) or "standby" (for standby suspend) or "freeze" (for suspend type freeze) diff --git a/arch/x86/virt/vmx/tdx.c b/arch/x86/virt/vmx/tdx.c index d9ad8dc7111e..2022f9c019b8 100644 --- a/arch/x86/virt/vmx/tdx.c +++ b/arch/x86/virt/vmx/tdx.c @@ -116,6 +116,16 @@ static struct tdsysinfo_struct tdx_sysinfo; /* TDX global KeyID to protect TDX metadata */ static u32 tdx_global_keyid; +static bool enable_tdx_host; + +static int __init tdx_host_setup(char *s) +{ + if (!strcmp(s, "on")) + enable_tdx_host = true; + return 1; +} +__setup("tdx_host=", tdx_host_setup); + static bool __seamrr_enabled(void) { return (seamrr_mask & SEAMRR_ENABLED_BITS) == SEAMRR_ENABLED_BITS; @@ -501,6 +511,10 @@ static int detect_p_seamldr(void) static int __tdx_detect(void) { + /* Disabled by kernel command line */ + if (!enable_tdx_host) + goto no_tdx_module; + /* The TDX module is not loaded if SEAMRR is disabled */ if (!seamrr_enabled()) { pr_info("SEAMRR not enabled.\n"); -- 2.35.1