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 68607C43334 for ; Fri, 24 Jun 2022 11:22:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230474AbiFXLWI (ORCPT ); Fri, 24 Jun 2022 07:22:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48938 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229584AbiFXLWG (ORCPT ); Fri, 24 Jun 2022 07:22:06 -0400 Received: from mga18.intel.com (mga18.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8342079465; Fri, 24 Jun 2022 04:22:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1656069725; x=1687605725; h=message-id:subject:from:to:cc:date:in-reply-to: references:content-transfer-encoding:mime-version; bh=TqMaSYDiPwgOdjjOGF2zwrDO0PbjQMwjiYFS1UhbBm8=; b=YVEF//9tOZFfUAV97m8kEdPf0nsVz1FR/n50agr9aZjl/jTRk3rtl6jU y2nMqoYF5s9s2G96gaOmiMrukfyXGcCuuRRDp4O8Iy3frU1RaT6hGYmYU u6MsF9pbsDHkUepzYAPbTe3JAf+5ZPu0KkihJhCsfDrYGGRnHDZJRVU1l NFHklGs2zrsMBKY/mDBxYSKAShYn4BesjhEovVwL9xxnysgiMoki6gkUj e0sG0aGWx9LUcqf0qpuDwzJ7Vqzzxe+Rdv5CBkRm9V9cgjimf0P8SUnnh MJ8zsHFvWanREunyzN9c0VxL4pGb41cmzg9BEDQxnWU5nRleuHiE6uC46 A==; X-IronPort-AV: E=McAfee;i="6400,9594,10387"; a="264019964" X-IronPort-AV: E=Sophos;i="5.92,218,1650956400"; d="scan'208";a="264019964" Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Jun 2022 04:22:05 -0700 X-IronPort-AV: E=Sophos;i="5.92,218,1650956400"; d="scan'208";a="835089568" Received: from jvrobert-mobl.amr.corp.intel.com (HELO khuang2-desk.gar.corp.intel.com) ([10.212.99.67]) by fmsmga006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Jun 2022 04:22:01 -0700 Message-ID: <951da5eeb4214521635602ce3564246ad49018f5.camel@intel.com> Subject: Re: [PATCH v5 04/22] x86/virt/tdx: Prevent ACPI CPU hotplug and ACPI memory hotplug From: Kai Huang To: Chao Gao Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, seanjc@google.com, pbonzini@redhat.com, dave.hansen@intel.com, len.brown@intel.com, tony.luck@intel.com, rafael.j.wysocki@intel.com, reinette.chatre@intel.com, dan.j.williams@intel.com, peterz@infradead.org, ak@linux.intel.com, kirill.shutemov@linux.intel.com, sathyanarayanan.kuppuswamy@linux.intel.com, isaku.yamahata@intel.com, thomas.lendacky@amd.com, Tianyu.Lan@microsoft.com Date: Fri, 24 Jun 2022 23:21:59 +1200 In-Reply-To: <20220624014112.GA15566@gao-cwp> References: <3a1c9807d8c140bdd550cd5736664f86782cca64.1655894131.git.kai.huang@intel.com> <20220624014112.GA15566@gao-cwp> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.44.2 (3.44.2-1.fc36) MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2022-06-24 at 09:41 +0800, Chao Gao wrote: > On Wed, Jun 22, 2022 at 11:16:07PM +1200, Kai Huang wrote: > > -static bool intel_cc_platform_has(enum cc_attr attr) > > +#ifdef CONFIG_INTEL_TDX_GUEST > > +static bool intel_tdx_guest_has(enum cc_attr attr) > > { > > switch (attr) { > > case CC_ATTR_GUEST_UNROLL_STRING_IO: > > @@ -28,6 +31,33 @@ static bool intel_cc_platform_has(enum cc_attr attr) > > return false; > > } > > } > > +#endif > > + > > +#ifdef CONFIG_INTEL_TDX_HOST > > +static bool intel_tdx_host_has(enum cc_attr attr) > > +{ > > + switch (attr) { > > + case CC_ATTR_ACPI_CPU_HOTPLUG_DISABLED: > > + case CC_ATTR_ACPI_MEMORY_HOTPLUG_DISABLED: > > + return true; > > + default: > > + return false; > > + } > > +} > > +#endif > > + > > +static bool intel_cc_platform_has(enum cc_attr attr) > > +{ > > +#ifdef CONFIG_INTEL_TDX_GUEST > > + if (boot_cpu_has(X86_FEATURE_TDX_GUEST)) > > + return intel_tdx_guest_has(attr); > > +#endif > > +#ifdef CONFIG_INTEL_TDX_HOST > > + if (platform_tdx_enabled()) > > + return intel_tdx_host_has(attr); > > +#endif > > + return false; > > +} >=20 > how about: >=20 > static bool intel_cc_platform_has(enum cc_attr attr) > { > switch (attr) { > /* attributes applied to TDX guest only */ > case CC_ATTR_GUEST_UNROLL_STRING_IO: > ... > return boot_cpu_has(X86_FEATURE_TDX_GUEST); >=20 > /* attributes applied to TDX host only */ > case CC_ATTR_ACPI_CPU_HOTPLUG_DISABLED: > case CC_ATTR_ACPI_MEMORY_HOTPLUG_DISABLED: > return platform_tdx_enabled(); >=20 > default: > return false; > } > } >=20 > so that we can get rid of #ifdef/endif. Personally I don't quite like this way. To me having separate function for= host and guest is more clear and more flexible. And I don't think having #ifdef/endif has any problem. I would like to leave to maintainers. --=20 Thanks, -Kai