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 27766C7619A for ; Mon, 27 Mar 2023 06:30:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231976AbjC0Gae (ORCPT ); Mon, 27 Mar 2023 02:30:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48944 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232259AbjC0Gac (ORCPT ); Mon, 27 Mar 2023 02:30:32 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 43F0D3A9A; Sun, 26 Mar 2023 23:30:28 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id B50CB60FC6; Mon, 27 Mar 2023 06:30:27 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 607DEC433EF; Mon, 27 Mar 2023 06:30:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1679898626; bh=ju/d3q0v2bf5FDc4EUiRscamg6Isw0kzmX3UyI6cgCA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ZYv3p4//3I4ZFnwKiWQ8XJHI7UWl6RiSftpivRsW+GLQ7F2V5s4Ez43RwaO7oRc26 uy+SwxyfKE9r3MNjY7t/6uaTxU9DIfXAUpMqXTlcEHOZEQbvULPcwGA4UVtr3L0GVV AP1JnveRLuIfkOxa6DnQ83R0cIG/DOS+nV90ukKE= Date: Mon, 27 Mar 2023 08:30:24 +0200 From: Greg KH To: Sathyanarayanan Kuppuswamy Cc: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, Shuah Khan , Jonathan Corbet , "H . Peter Anvin" , "Kirill A . Shutemov" , Tony Luck , Wander Lairson Costa , Erdem Aktas , Guorui Yu , Du Fan , linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-doc@vger.kernel.org Subject: Re: [PATCH v1 2/3] virt: tdx-guest: Add Quote generation support Message-ID: References: <20230326062039.341479-1-sathyanarayanan.kuppuswamy@linux.intel.com> <20230326062039.341479-3-sathyanarayanan.kuppuswamy@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On Sun, Mar 26, 2023 at 12:06:26PM -0700, Sathyanarayanan Kuppuswamy wrote: > If usage of DMA APIs / platform device is not acceptable for this use case, It is not ok to use a platform device for this because you just do not have a platform device for it, don't make one up out of thin air please, as that really doesn't even have the correct bindings to the DMA memory that you want here. > an alternative approach is to allocate a fixed number of shared buffers during > the TDX guest driver probe and use it for GetQuote requests. Although it would > limit the amount of memory we can use for GetQuote requests at a time and also > reserve a chunk of memory during the init() time, I think it is an acceptable > tradeoff when compared to alternative choices. The AMD SEV guest driver also > adopts the similar approach. Please let me know if this approach is acceptable. This sounds like a better approach. thanks, greg k-h