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 99C3EC43217 for ; Mon, 28 Nov 2022 15:22:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229961AbiK1PWi (ORCPT ); Mon, 28 Nov 2022 10:22:38 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59386 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230057AbiK1PWg (ORCPT ); Mon, 28 Nov 2022 10:22:36 -0500 Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2CF0CCCF; Mon, 28 Nov 2022 07:22:35 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1669648955; x=1701184955; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=a/sB1/393ytlRa8eYq2hsxfrWcpUuWZKXU8+lFf1uQE=; b=acDRL2OuxWUAKbYxt1n4S0z0n05IchgwpVhelNBySGQnwgS8uF9+xjJe Re3nvklAPBjKqBfCG0DO0Skt/WP1H4Ea+GTIASG/v7eocirdJZ30/y57I bc985sBimgevpfRVtkQQNaDHtuQFmarYIDcQ0qwyyhWfBG4ZTLr3604c5 edsWeIZAxqkg3VAD2BvyOvHoXi9dcYw+7VaaKHAp9xkpzLKAZ1o22QQg4 R+8bnJUBVsPHmseKceUf9+RQTGT5xJGPURxG5BBjoD7y5BORL4OPxHcyz EQddhk/tdJKiej/tcEHxp9FgkryniYXKszvZQhS/r3bVKX4g5gayLqMvG g==; X-IronPort-AV: E=McAfee;i="6500,9779,10545"; a="302440513" X-IronPort-AV: E=Sophos;i="5.96,200,1665471600"; d="scan'208";a="302440513" Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Nov 2022 07:22:29 -0800 X-IronPort-AV: E=McAfee;i="6500,9779,10545"; a="621086442" X-IronPort-AV: E=Sophos;i="5.96,200,1665471600"; d="scan'208";a="621086442" Received: from nroy-mobl1.amr.corp.intel.com (HELO [10.212.209.4]) ([10.212.209.4]) by orsmga006-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Nov 2022 07:22:28 -0800 Message-ID: Date: Mon, 28 Nov 2022 07:22:27 -0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.2.2 Subject: Re: [PATCH 5/6] x86/hyperv: Support hypercalls for TDX guests Content-Language: en-US To: Dexuan Cui , "Michael Kelley (LINUX)" , "ak@linux.intel.com" , "arnd@arndb.de" , "bp@alien8.de" , "brijesh.singh@amd.com" , "Williams, Dan J" , "dave.hansen@linux.intel.com" , Haiyang Zhang , "hpa@zytor.com" , "jane.chu@oracle.com" , "kirill.shutemov@linux.intel.com" , KY Srinivasan , "linux-arch@vger.kernel.org" , "linux-hyperv@vger.kernel.org" , "luto@kernel.org" , "mingo@redhat.com" , "peterz@infradead.org" , "rostedt@goodmis.org" , "sathyanarayanan.kuppuswamy@linux.intel.com" , "seanjc@google.com" , "tglx@linutronix.de" , "tony.luck@intel.com" , "wei.liu@kernel.org" , "x86@kernel.org" Cc: "linux-kernel@vger.kernel.org" References: <20221121195151.21812-1-decui@microsoft.com> <20221121195151.21812-6-decui@microsoft.com> From: Dave Hansen In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-hyperv@vger.kernel.org On 11/27/22 16:58, Dexuan Cui wrote: > +u64 hv_tdx_hypercall(u64 control, u64 input_addr, u64 output_addr) > +{ > + struct tdx_hypercall_args args = { }; > + > + if (!(control & HV_HYPERCALL_FAST_BIT)) { > + if (input_addr) > + input_addr += ms_hyperv.shared_gpa_boundary; > + > + if (output_addr) > + output_addr += ms_hyperv.shared_gpa_boundary; > + } This: > https://learn.microsoft.com/en-us/virtualization/hyper-v-on-windows/tlfs/hypercall-interface makes it sound like HV_HYPERCALL_FAST_BIT says whether arguments go in registers (fast) or memory (slow). But this hv_tdx_hypercall() function looks like it takes addresses only. *Is* there a register based calling convention to make Hyper-V hypercalls when running under TDX? Also, is this the output address manipulation fundamentally different from: output_addr = cc_mkdec(output_addr); ? Decrypted addresses are the shared ones, right?