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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 94A44C433EF for ; Tue, 19 Jul 2022 22:02:32 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 2F7626B0073; Tue, 19 Jul 2022 18:02:32 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 2A6046B0074; Tue, 19 Jul 2022 18:02:32 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 16E7C6B0075; Tue, 19 Jul 2022 18:02:32 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 0971A6B0073 for ; Tue, 19 Jul 2022 18:02:32 -0400 (EDT) Received: from smtpin14.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id D125412037F for ; Tue, 19 Jul 2022 22:02:31 +0000 (UTC) X-FDA: 79705224102.14.92B2318 Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by imf20.hostedemail.com (Postfix) with ESMTP id D4CB41C009C for ; Tue, 19 Jul 2022 22:02:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1658268150; x=1689804150; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=zqYQJv/XFExUA8Fi57QQgZNmV5/oX/XVpYLW9fg17RU=; b=lQF3KKA+Tdyq0QfYKVVgYdRzerFavtSmHCX9c1u30LIk1Cg3hJi/5PQf ZoDxQZQvb5RGqGmDJb5S8L5+elATR4tryCC4Z6HEl/391Lt6xHBYNSs/g xeXjx/hJTf0SIKWidBnvN6nj0cUhUCKyv7rSFiW4IqPMPQ1kzaTdUlSyB P5VDTw/IG2owvBW5I9Xp6Bap32hxubpnFCqTQQAyWpZWY58YIolXrb+5F VGpcx6jAiGMp5QcsOkRtsOpyGbK2/rjh6y5USj94sn7dsbzOPH/rgWEkK FgcqG3hTUQGGwcsdqsU0VRiRC+J7RisdmEIHdPEoLKtRWNFzHFOnZXRck g==; X-IronPort-AV: E=McAfee;i="6400,9594,10413"; a="273454515" X-IronPort-AV: E=Sophos;i="5.92,285,1650956400"; d="scan'208";a="273454515" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Jul 2022 15:02:29 -0700 X-IronPort-AV: E=Sophos;i="5.92,285,1650956400"; d="scan'208";a="687279751" Received: from twliston-mobl1.amr.corp.intel.com (HELO [10.212.132.190]) ([10.212.132.190]) by fmsmga003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Jul 2022 15:02:27 -0700 Message-ID: <22d54786-bc12-ecc5-2b37-cbaa56090aa8@intel.com> Date: Tue, 19 Jul 2022 15:02:26 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.9.1 Subject: Re: [PATCHv7 00/14] mm, x86/cc: Implement support for unaccepted memory Content-Language: en-US To: Borislav Petkov Cc: Ard Biesheuvel , Dionna Amalie Glaze , "Kirill A. Shutemov" , Peter Gonda , Andy Lutomirski , Sean Christopherson , Andrew Morton , Joerg Roedel , Andi Kleen , Kuppuswamy Sathyanarayanan , David Rientjes , Vlastimil Babka , Tom Lendacky , Thomas Gleixner , Peter Zijlstra , Paolo Bonzini , Ingo Molnar , Varad Gautam , Dario Faggioli , Mike Rapoport , David Hildenbrand , Marcelo Cerri , tim.gardner@canonical.com, Khalid ElMously , philip.cox@canonical.com, the arch/x86 maintainers , Linux Memory Management List , linux-coco@lists.linux.dev, linux-efi , LKML , "Yao, Jiewen" References: <20220627223808.ihgy3epdx6ofll43@black.fi.intel.com> <20220718172159.4vwjzrfthelovcty@black.fi.intel.com> From: Dave Hansen In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1658268151; a=rsa-sha256; cv=none; b=xTuCNOFhXHSsxDiVlnhHJizBtvHZd6GSKzO0Q4c5hOCukpACAVtv7ogM+KJT6SxRMWCRFv pibjfJlaBmnXlaKTzyRfXsfh9b/AI9ywB/nNUi99HtsSUt4xQN/4qWncTCkuqimKst3ypq EbKvO2oSQFQyML3ifdExGRgAAO4jfdE= ARC-Authentication-Results: i=1; imf20.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=lQF3KKA+; spf=none (imf20.hostedemail.com: domain of dave.hansen@intel.com has no SPF policy when checking 134.134.136.20) smtp.mailfrom=dave.hansen@intel.com; dmarc=pass (policy=none) header.from=intel.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1658268151; h=from:from:sender: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:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=ianiz0+RScUIH5f4Ql9Zk9SAn7GAWXK67vWDT+OhWlc=; b=vUaxYPyufgNyJiXqxBaEgEvcEy/4+fUtszPJDz2ekVYEY8iUo5xlcG4WbNlXXAAJVId9SC 42yb95aI/QExoG7lPQrj2IwS3s9K5Beg6xVI5+pOD6PTN1o3z8tdoggxlXPmbKSr30nKd/ kQ9RWAeO6zYCtfi59x+kbSsFbtSUm04= X-Stat-Signature: a9m7x37m76pgw8mce4w8jjx8u4yxt8g3 X-Rspamd-Queue-Id: D4CB41C009C Authentication-Results: imf20.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=lQF3KKA+; spf=none (imf20.hostedemail.com: domain of dave.hansen@intel.com has no SPF policy when checking 134.134.136.20) smtp.mailfrom=dave.hansen@intel.com; dmarc=pass (policy=none) header.from=intel.com X-Rspam-User: X-Rspamd-Server: rspam10 X-HE-Tag: 1658268150-720193 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 7/19/22 14:50, Borislav Petkov wrote: > On Tue, Jul 19, 2022 at 02:35:45PM -0700, Dave Hansen wrote: >> They're trying to design something that can (forever) handle guests that >> might not be able to accept memory. > Wait, what? > > If you can't modify those guests to teach them to accept memory, how do > you add TDX or SNP guest support to them? Mainline today, for instance, doesn't have unaccepted memory support for TDX or SEV-SNP guests. But, they both still boot fine because folks either configure it on the host side not to *have* any unaccepted memory. Or, they just live with the small (4GB??) amount of pre-accepted memory, which is fine for testing things.