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 9D1D8C4332F for ; Tue, 29 Nov 2022 08:40:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230041AbiK2Ikw (ORCPT ); Tue, 29 Nov 2022 03:40:52 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50884 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229457AbiK2Ikt (ORCPT ); Tue, 29 Nov 2022 03:40:49 -0500 Received: from mail.skyhub.de (mail.skyhub.de [IPv6:2a01:4f8:190:11c2::b:1457]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A28092D4; Tue, 29 Nov 2022 00:40:48 -0800 (PST) Received: from zn.tnic (p5de8e9fe.dip0.t-ipconnect.de [93.232.233.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id 2F66B1EC04AD; Tue, 29 Nov 2022 09:40:47 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1669711247; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=LtafUuhoGhuxiOxEKxOMOok0bCWTN1htaAAgYkWpfmw=; b=i5XWBIBr7fytFgs7Uf48RLs5dWMHp5K+KK9mvmX6p+c/f8RiFg1SkSTuEH3YhFg2LUJpue 0Xgl2zSKsATfHJFPsmiZbVgMxftc/Rlo/tFBkhM3/tkfCFrnhCPpLzT8jsQEis6ic4I2KS Ai7bkeoFc5//t614TyupdVgfKsrswu4= Date: Tue, 29 Nov 2022 09:40:46 +0100 From: Borislav Petkov To: "Michael Kelley (LINUX)" Cc: "hpa@zytor.com" , KY Srinivasan , Haiyang Zhang , "wei.liu@kernel.org" , Dexuan Cui , "luto@kernel.org" , "peterz@infradead.org" , "davem@davemloft.net" , "edumazet@google.com" , "kuba@kernel.org" , "pabeni@redhat.com" , "lpieralisi@kernel.org" , "robh@kernel.org" , "kw@linux.com" , "bhelgaas@google.com" , "arnd@arndb.de" , "hch@infradead.org" , "m.szyprowski@samsung.com" , "robin.murphy@arm.com" , "thomas.lendacky@amd.com" , "brijesh.singh@amd.com" , "tglx@linutronix.de" , "mingo@redhat.com" , "dave.hansen@linux.intel.com" , Tianyu Lan , "kirill.shutemov@linux.intel.com" , "sathyanarayanan.kuppuswamy@linux.intel.com" , "ak@linux.intel.com" , "isaku.yamahata@intel.com" , "Williams, Dan J" , "jane.chu@oracle.com" , "seanjc@google.com" , "tony.luck@intel.com" , "x86@kernel.org" , "linux-kernel@vger.kernel.org" , "linux-hyperv@vger.kernel.org" , "netdev@vger.kernel.org" , "linux-pci@vger.kernel.org" , "linux-arch@vger.kernel.org" , "iommu@lists.linux.dev" Subject: Re: [Patch v3 07/14] x86/hyperv: Change vTOM handling to use standard coco mechanisms Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Nov 29, 2022 at 01:15:39AM +0000, Michael Kelley (LINUX) wrote: > So that's why I'm suggesting CC_VENDOR_AMD_VTOM. There's no CC_VENDOR_AMD_VTOM. How many times do I need to explain this?! CC_VENDOR is well the CC vendor - not some special case. IOW, the goal here is for generic SNP functionality to be the same for *all* SNP guests. We won't do the AMD's version of vTOM enablement, Hyper-V's version of vTOM enablement and so on. It must be a single vTOM feature which works on *all* hypervisors as vTOM is a generic SNP feature - not Hyper-V feature. > Of course, when you go from N=1 hypervisors (i.e., KVM) to N=2 (KVM > and Hyper-V, you find some places where incorrect assumptions were > made or some generalizations are needed. Dexuan Cui's patch set for > TDX support is fixing those places that he has encountered. But with > those fixes, the TDX support will JustWork(tm) for Linux guests on > Hyper-V. That sounds like the right direction to take. > I haven't gone deeply into the situation with AMD C-bit support on > Hyper-V. Tianyu Lan's set of patches for that support is a bit bigger, > and I'm planning to look closely to understand whether it's also just > fixing incorrect assumptions and such, or whether they really are > some differences with Hyper-V. If there are differences, I want to > understand why. You and me too. So I guess we should look at Tianyu's set first. Thx. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette