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 63821C7EE24 for ; Mon, 5 Jun 2023 19:19:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235590AbjFETTk (ORCPT ); Mon, 5 Jun 2023 15:19:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40528 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235672AbjFETTZ (ORCPT ); Mon, 5 Jun 2023 15:19:25 -0400 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 70A411AD; Mon, 5 Jun 2023 12:18:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1685992723; x=1717528723; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=Kt8UwcbAWIHbjuRkCIkoTQ1Kj/ybAb+bYpOZY2j+aQA=; b=Sr9XK2l6EeD6MuNr2ZQRiR151Rg0jugohDppNKl3CQ65CBHdzpiwgjgG n5K7WiJ/ERg5p1Ug0oZKT3mlSOubjloTa5/puepjXHSDy+odxltzroH5z PyZ1lkE6LCQAWHKmdTWBSVybk/aKk1hbpslSRrYcIBX4j31AuMhtGZYkB KBZIPe6qU+W9+yOjXk0hX+Q9VFD7Vn5gW7hGDmn9113qK+nkRNm+YmCQ/ yKmIrrSdYEe0CSkZ95Dz9solGqTkhFnPp3VCeEi6OtDeizNEAYQjMNsl2 afk+vHUHTAZ3SyhQUVKnJXMTmtnDvn7d09xRQPQyNn8744dho2smsKq+u w==; X-IronPort-AV: E=McAfee;i="6600,9927,10732"; a="422284836" X-IronPort-AV: E=Sophos;i="6.00,218,1681196400"; d="scan'208";a="422284836" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Jun 2023 12:18:24 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10732"; a="711919843" X-IronPort-AV: E=Sophos;i="6.00,218,1681196400"; d="scan'208";a="711919843" Received: from pmudgal-mobl1.amr.corp.intel.com (HELO [10.209.41.254]) ([10.209.41.254]) by fmsmga007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Jun 2023 12:18:22 -0700 Message-ID: <5bce4a75-d4bb-74c2-1feb-e988841d5465@intel.com> Date: Mon, 5 Jun 2023 12:18:21 -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: [PATCHv13 9/9] x86/tdx: Add unaccepted memory support Content-Language: en-US To: Tom Lendacky , "Kirill A. Shutemov" , Borislav Petkov , Andy Lutomirski , Sean Christopherson , Andrew Morton , Joerg Roedel , Ard Biesheuvel Cc: Andi Kleen , Kuppuswamy Sathyanarayanan , David Rientjes , Vlastimil Babka , Thomas Gleixner , Peter Zijlstra , Paolo Bonzini , Ingo Molnar , Dario Faggioli , Mike Rapoport , David Hildenbrand , Mel Gorman , marcelo.cerri@canonical.com, tim.gardner@canonical.com, khalid.elmously@canonical.com, philip.cox@canonical.com, aarcange@redhat.com, peterx@redhat.com, x86@kernel.org, linux-mm@kvack.org, linux-coco@lists.linux.dev, linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org References: <20230601182543.19036-1-kirill.shutemov@linux.intel.com> <20230601182543.19036-10-kirill.shutemov@linux.intel.com> <4d8d6fc4-99b5-29ba-7f81-12e7d57907ea@amd.com> <1d24355c-3922-d5c7-4c05-f5ef0adaf5d2@amd.com> From: Dave Hansen In-Reply-To: <1d24355c-3922-d5c7-4c05-f5ef0adaf5d2@amd.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 6/2/23 07:26, Tom Lendacky wrote: >> So this is a change in this version. If tdx_accept_memory() fails, >> you'll report unknown platform. Wouldn't it be better to have an error >> message that indicates a failure in the accept path? >> > > Maybe you can keep it similar to the v12 version with just a new error > message, something like: > >     if (early_is_tdx_guest()) { >         if (!tdx_accept_memory(start, end)) >             error("TDX error accepting memory\n"); >     } else { >         error("Cannot accept memory: unknown platform\n"); >     } In the end, these errors aren't plumbed out to the page allocator. They *need* to succeed or we are dead anyway. Should we just send a fatal error up to the TDX module when we fail to accept memory? It's _slightly_ less opaque than plowing into an unaccepted page.