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 48F22C43334 for ; Fri, 24 Jun 2022 16:57:53 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A5E1D6B0073; Fri, 24 Jun 2022 12:57:52 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A0EA76B0075; Fri, 24 Jun 2022 12:57:52 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8D58C8E020E; Fri, 24 Jun 2022 12:57:52 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 7F7086B0073 for ; Fri, 24 Jun 2022 12:57:52 -0400 (EDT) Received: from smtpin05.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 298058A0 for ; Fri, 24 Jun 2022 16:57:52 +0000 (UTC) X-FDA: 79613736384.05.3431F7B Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by imf25.hostedemail.com (Postfix) with ESMTP id 122FAA002D for ; Fri, 24 Jun 2022 16:57:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1656089871; x=1687625871; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=h9unbbnqGQL7IjxvTCwmIkRm1Ll3fd9IcwkzJE10U7I=; b=a61fxbJ04yQYVM9x0lWD5NRMGql8QvINEM3gQF7BWJchtHkRHTtjz73s T1NFUPpB0Z3N2QJ9y1+ZHOyU775VYkAresb7lYTbBeA7Mns4GZVNpISTY ZbzhjgK6Llqd9vZKaFJ/t/Tv6oHww8hyaPVOojh4Y9XB7xmcQL0nGHC8t VKnLbgu1XzBfGVb+n6gfQaef166BOnpjuN0KB76QeehVBmccvR85AlaB/ lN+BB6MRB+QkWzVZJKu2jtL7PXgUel2lDUtw9lZyWPgs22oa8eXbhu4G5 LdCpTJEQUzrpZNTNfrwSQBkQPTh5Q78XassBWs6QrUWV3UaLjv1M3e/7z w==; X-IronPort-AV: E=McAfee;i="6400,9594,10388"; a="306507056" X-IronPort-AV: E=Sophos;i="5.92,218,1650956400"; d="scan'208";a="306507056" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Jun 2022 09:57:49 -0700 X-IronPort-AV: E=Sophos;i="5.92,218,1650956400"; d="scan'208";a="731393321" Received: from mdedeogl-mobl.amr.corp.intel.com (HELO [10.209.126.186]) ([10.209.126.186]) by fmsmga001-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Jun 2022 09:57:48 -0700 Message-ID: <5af19000-4482-7eb9-f158-0a461891f087@intel.com> Date: Fri, 24 Jun 2022 09:57:14 -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: Peter Gonda , "Kirill A. Shutemov" Cc: Borislav Petkov , Andy Lutomirski , Sean Christopherson , Andrew Morton , Joerg Roedel , Ard Biesheuvel , 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@canonical.com, tim.gardner@canonical.com, khalid.elmously@canonical.com, philip.cox@canonical.com, the arch/x86 maintainers , linux-mm@kvack.org, linux-coco@lists.linux.dev, linux-efi@vger.kernel.org, LKML References: <20220614120231.48165-1-kirill.shutemov@linux.intel.com> From: Dave Hansen In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit ARC-Authentication-Results: i=1; imf25.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=a61fxbJ0; dmarc=pass (policy=none) header.from=intel.com; spf=none (imf25.hostedemail.com: domain of dave.hansen@intel.com has no SPF policy when checking 192.55.52.88) smtp.mailfrom=dave.hansen@intel.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1656089871; a=rsa-sha256; cv=none; b=WbSJgauiz9uerWRtoivR5bWMVLgpKogRvXrOZscFO4uue4HDQhVhFEVB+OyT5vxn2iCFIr zVEvpK8ITUXFpisrcSBq6wEmfiyx9h/EHv/kL4kibBvkZNOmEpvm7bnW/JLJ1CwRibJS5I lYIrtul8APgt9AdX6QOiULFDC+k1nTk= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1656089871; 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=Fr0CO+cZterQf0u4q2SQWsfOK/VETJJHaKwkKAzcroM=; b=cNKxVgUffEByudZzaoi13F3xWdhShIkUz32E1DbRfzXf+3oCAoHMlnC1jDKPbHF4QIT7tD 5/2TwcEuXjvw2qTQR/SqglU5IDaKQlT8Ud5VecitU6Ls8NAmrG1n2DlOVLq+BgXsw5vDhY ACTmtvE0nZZuWNrFBfXMQuradf2NfPw= X-Stat-Signature: fbmykytmzw5xejmpbuq41w5rh8mjucii X-Rspamd-Server: rspam08 X-Rspam-User: X-Rspamd-Queue-Id: 122FAA002D Authentication-Results: imf25.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=a61fxbJ0; dmarc=pass (policy=none) header.from=intel.com; spf=none (imf25.hostedemail.com: domain of dave.hansen@intel.com has no SPF policy when checking 192.55.52.88) smtp.mailfrom=dave.hansen@intel.com X-HE-Tag: 1656089870-451512 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: Peter, is your enter key broken? You seem to be typing all your text in a single unreadable paragraph. On 6/24/22 09:37, Peter Gonda wrote: > if a customer incorrectly labels their image it may fail to boot.. You're saying that firmware basically has two choices: 1. Accept all the memory up front and boot slowly, but reliably 2. Use thus "unaccepted memory" mechanism, boot fast, but risk that the VM loses a bunch of memory. If the guest can't even boot because of a lack of memory, then the pre-accepted chunk is probably too small in the first place. If the customer screws up, they lose a bunch of the RAM they paid for. That seems like a rather self-correcting problem to me.