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 1DF09C43334 for ; Fri, 24 Jun 2022 17:19:20 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id ADC0E8E023C; Fri, 24 Jun 2022 13:19:19 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A8C258E020E; Fri, 24 Jun 2022 13:19:19 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 97AA38E023C; Fri, 24 Jun 2022 13:19:19 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 885188E020E for ; Fri, 24 Jun 2022 13:19:19 -0400 (EDT) Received: from smtpin28.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 605B7207BD for ; Fri, 24 Jun 2022 17:19:19 +0000 (UTC) X-FDA: 79613790438.28.C9C19E8 Received: from mail-oi1-f169.google.com (mail-oi1-f169.google.com [209.85.167.169]) by imf31.hostedemail.com (Postfix) with ESMTP id 17E7220007 for ; Fri, 24 Jun 2022 17:19:18 +0000 (UTC) Received: by mail-oi1-f169.google.com with SMTP id s124so4470968oia.0 for ; Fri, 24 Jun 2022 10:19:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=oNiiFv53teFu3CRex5rCry8QLqLkd97P3Hj9fAhbeYc=; b=kFAUNKf1rEgkt+OYkPh8tB9E+HPlRDJ57kjd7aaOhWKcIYCN/ZjVerEUwL1D4UqEy6 jNB2akz9JlmI2z3ciS9Jkc2XEeGMl3dvnEZrG1QqRu/ya7j4cL/8FovPHxIwC5EW6es7 Ghq27j3amQkzIckOMXvVOxDa7HU8mwaHoI3RREC2uB5mU26z2mV8kUwNG56nJSMHMRqc 7XxJo0dYVvBtJQS7ebwKtCv1V87zEy9YAPcRV8rTLCfAJuZvL7bdAFhpoy8DPcdAukCV I/VMctopfL4nnKopG199aqN6z+kRpGu+YbvvSx5/icPAGuQh+9wvM0ZMI9vQVocoE5BI 2jZg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=oNiiFv53teFu3CRex5rCry8QLqLkd97P3Hj9fAhbeYc=; b=Hgu07pHIYkCk0W+TNlAT5tITHSCdEK5R2CIc2mraTDysuSfQaWKzGV7ZO8ppTsy9iJ SNhMIu51ocanW8X9/KThzRxbgyt2GMUuLWZM6/pNcU+/u1mN3npyZx1SI4usxwqxrhtt A9xuxp4TZWPFJ8aJravoR70pcy57HXwU5RJn55RW40foll/i2OVKua1q/pIuq6smIDNN BhyVUp/8MUuj082v4YKRIeQtCTv3RT31+o7+dPZ0XM1mG+YCnpHntLCyPN3dHf5C69hE jKGTy9W3i5GbADp3nND6HrRFTpGOCL+jspGIQBJ3gl1k9VlCr/ogClNGlA48G+FaoIy+ +4eQ== X-Gm-Message-State: AJIora/fc6x6WOoQlvsogmtn9GWkDhMLb84rEpRNx0/K9PgZFWo1AUhL 0ieQzxfrtB8uC9amdC0zZrUxeCLCZwrnhN5MA0YrxA== X-Google-Smtp-Source: AGRyM1vH1Tmei+FucmqSWTWHKYA82g8W5CxsahmZ6gIJ+zkpr7Odp70Gu50EcpESE80fWGtWYk5jJ9pFsVncC/eeohY= X-Received: by 2002:a05:6808:179a:b0:32f:2b07:e733 with SMTP id bg26-20020a056808179a00b0032f2b07e733mr2572280oib.218.1656091158204; Fri, 24 Jun 2022 10:19:18 -0700 (PDT) MIME-Version: 1.0 References: <20220614120231.48165-1-kirill.shutemov@linux.intel.com> <5af19000-4482-7eb9-f158-0a461891f087@intel.com> In-Reply-To: From: Marc Orr Date: Fri, 24 Jun 2022 10:19:07 -0700 Message-ID: Subject: Re: [PATCHv7 00/14] mm, x86/cc: Implement support for unaccepted memory To: Dave Hansen Cc: Peter Gonda , "Kirill A. Shutemov" , 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 , tim.gardner@canonical.com, Khalid ElMously , philip.cox@canonical.com, "the arch/x86 maintainers" , linux-mm@kvack.org, linux-coco@lists.linux.dev, linux-efi@vger.kernel.org, LKML Content-Type: text/plain; charset="UTF-8" ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1656091159; 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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=oNiiFv53teFu3CRex5rCry8QLqLkd97P3Hj9fAhbeYc=; b=grGZ9NHq9ufG0nX3ZsQIXdpmJzPd4AeDjDsyUqSTw5BVtM/RFNauAbs8NfldF0knVyVNg7 gVTYpnXVf0o7PWAnAPs9eRPgdUrvqEpIF+ayicz4yBrnCLuRmsncFt79ShKdG8ZkaWEQV3 TjR/w7WeZUbr6KW1dIszWdx38nL6SMI= ARC-Authentication-Results: i=1; imf31.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=kFAUNKf1; spf=pass (imf31.hostedemail.com: domain of marcorr@google.com designates 209.85.167.169 as permitted sender) smtp.mailfrom=marcorr@google.com; dmarc=pass (policy=reject) header.from=google.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1656091159; a=rsa-sha256; cv=none; b=H7atA0LbiqlbJs4J3TLl+0CO7UwyeziyRmiUPwbVLyQz4NTyaZjK5Zx8nhQf6nvUXa2I6p URdNh+IGNvLAVkkQ9jesb59IrKp7LgFQrgAWL2kO0D+NjzK7/QW9p2DwzDS8WzhvLVTHeX tZs4HJ44bgebYvl8Agz2q+5cKfxMSD8= Authentication-Results: imf31.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=kFAUNKf1; spf=pass (imf31.hostedemail.com: domain of marcorr@google.com designates 209.85.167.169 as permitted sender) smtp.mailfrom=marcorr@google.com; dmarc=pass (policy=reject) header.from=google.com X-Rspam-User: X-Rspamd-Server: rspam06 X-Stat-Signature: 8dkcwoki8hcqdrfhkkrwbhymmjdtbbma X-Rspamd-Queue-Id: 17E7220007 X-HE-Tag: 1656091158-571591 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 Fri, Jun 24, 2022 at 10:10 AM Dave Hansen wrote: > > On 6/24/22 10:06, Marc Orr wrote: > > I think Peter's point is a little more nuanced than that. Once lazy > > accept goes into the guest firmware -- without the feature negotiation > > that Peter is suggesting -- cloud providers now have a bookkeeping > > problem. Which images have kernels that can boot from a guest firmware > > that doesn't pre-validate all the guest memory? > > Hold on a sec though... > > Is this a matter of > > can boot from a guest firmware that doesn't pre-validate all the > guest memory? > > or > > can boot from a guest firmware that doesn't pre-validate all the > guest memory ... with access to all of that guest's RAM? > > In other words, are we talking about "fails to boot" or "can't see all > the RAM"? Ah... yeah, you're right, Dave -- I guess it's the latter. The guest won't have access to all of the memory that the customer is paying for. But that's still bad. If the customer buys a 96 GB VM and can only see 4GB because they're kernel doesn't have these patches they're going to be confused and frustrated.