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 4742FEB64D8 for ; Wed, 21 Jun 2023 14:31:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229755AbjFUObi (ORCPT ); Wed, 21 Jun 2023 10:31:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44490 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229513AbjFUObh (ORCPT ); Wed, 21 Jun 2023 10:31:37 -0400 Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6279612E; Wed, 21 Jun 2023 07:31:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1687357895; x=1718893895; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=O64wJ4h2FjMBRHsbamypZL1GWJNUE5Ay/zmz6Kb6Fbw=; b=QhJVop2jENEPwjbKZntHyZiGNSZuKE3HfYuEE0+NAvFXXjcyocIRV88t vZplUd9p33m6ayvnl9Lb1hBdc+VfbcbD92jJBsxXK6nKwId7LAzjXfgnc ZdSdnmcy/KmnUWb7Mtc+HZvfvNBbnUlj/6uqmYhmy4/LUrByzEjmagPRo MADNBAjNYtp5lQBdom4io7OSJVfsgLsX7TF4wY9pWCczkKP/wLmvgLvY3 T1H7T78oenkkDqvuwC9wljseueIpAdp8NOy1Ti1F2sAE6dAT62AAVWWfD btQUaoxXudpNtliBp1xYMKcG+fpOAM5E/JHNAw/6jL0G+XEZ8Jy/NT40t g==; X-IronPort-AV: E=McAfee;i="6600,9927,10748"; a="349921498" X-IronPort-AV: E=Sophos;i="6.00,260,1681196400"; d="scan'208";a="349921498" Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Jun 2023 07:31:34 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10748"; a="714507270" X-IronPort-AV: E=Sophos;i="6.00,260,1681196400"; d="scan'208";a="714507270" Received: from rmathew-mobl2.amr.corp.intel.com (HELO [10.212.134.235]) ([10.212.134.235]) by orsmga002-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Jun 2023 07:31:34 -0700 Message-ID: <23f400bc-9a62-be4a-6a24-0e2149d4491c@intel.com> Date: Wed, 21 Jun 2023 07:31:34 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.11.0 Subject: Re: [PATCH RFC v9 07/51] x86/sev: Add the host SEV-SNP initialization support Content-Language: en-US To: Borislav Petkov Cc: Michael Roth , kvm@vger.kernel.org, linux-coco@lists.linux.dev, linux-mm@kvack.org, linux-crypto@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org, tglx@linutronix.de, mingo@redhat.com, jroedel@suse.de, thomas.lendacky@amd.com, hpa@zytor.com, ardb@kernel.org, pbonzini@redhat.com, seanjc@google.com, vkuznets@redhat.com, jmattson@google.com, luto@kernel.org, dave.hansen@linux.intel.com, slp@redhat.com, pgonda@google.com, peterz@infradead.org, srinivas.pandruvada@linux.intel.com, rientjes@google.com, dovmurik@linux.ibm.com, tobin@ibm.com, vbabka@suse.cz, kirill@shutemov.name, ak@linux.intel.com, tony.luck@intel.com, marcorr@google.com, sathyanarayanan.kuppuswamy@linux.intel.com, alpergun@google.com, dgilbert@redhat.com, jarkko@kernel.org, ashish.kalra@amd.com, nikunj.dadhania@amd.com, liam.merwick@oracle.com, zhi.a.wang@intel.com, Brijesh Singh References: <20230612042559.375660-1-michael.roth@amd.com> <20230612042559.375660-8-michael.roth@amd.com> <12f95b38-427c-6810-373a-ba2062c43882@intel.com> <20230621091541.GEZJK/veTnfhOnX8ci@fat_crate.local> From: Dave Hansen In-Reply-To: <20230621091541.GEZJK/veTnfhOnX8ci@fat_crate.local> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On 6/21/23 02:15, Borislav Petkov wrote: > On Mon, Jun 12, 2023 at 08:34:02AM -0700, Dave Hansen wrote: >> On 6/11/23 21:25, Michael Roth wrote: >>> + /* >>> + * Calculate the amount the memory that must be reserved by the BIOS to >>> + * address the whole RAM, including the bookkeeping area. The RMP itself >>> + * must also be covered. >>> + */ >>> + max_rmp_pfn = max_pfn; >>> + if (PHYS_PFN(rmp_end) > max_pfn) >>> + max_rmp_pfn = PHYS_PFN(rmp_end); >> Could you say a little here about how this deals with memory hotplug? > Does SNP hw even support memory hotplug? > > I think in order to support that, you'd need some special dance because > of the RMP table etc... Yep, there's the hardware side and then there are fun nuggets like using mem= and then doing a software-only hot-add later after boot. Also, if the hardware doesn't support any kind of hotplug, it would be great to point to the place in the spec where it says that.