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 0F6FAC02197 for ; Sat, 14 Sep 2024 13:34:52 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 8ACF46B0083; Sat, 14 Sep 2024 09:34:51 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 85DDA6B0088; Sat, 14 Sep 2024 09:34:51 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 6FCCA6B0089; Sat, 14 Sep 2024 09:34:51 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 528526B0083 for ; Sat, 14 Sep 2024 09:34:51 -0400 (EDT) Received: from smtpin17.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id F268C16205C for ; Sat, 14 Sep 2024 13:34:50 +0000 (UTC) X-FDA: 82563439140.17.D225916 Received: from mail-wm1-f49.google.com (mail-wm1-f49.google.com [209.85.128.49]) by imf22.hostedemail.com (Postfix) with ESMTP id 2AD57C0007 for ; Sat, 14 Sep 2024 13:34:48 +0000 (UTC) Authentication-Results: imf22.hostedemail.com; dkim=pass header.d=google.com header.s=20230601 header.b=Srq0XYU3; spf=pass (imf22.hostedemail.com: domain of vannapurve@google.com designates 209.85.128.49 as permitted sender) smtp.mailfrom=vannapurve@google.com; dmarc=pass (policy=reject) header.from=google.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1726320859; 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=dHM/9nGeV0kB5TjHKKHKGDZ6zh5A8DGqa4bFzJrKT/U=; b=0Uunu6jPbwq7wYnxxtWpJXJwAUr4eLOU4u+6dm+a5PMeNLMUa8pAWzTct8XFb8Qyqv3VGy jSWtCMwek0IVh/Foy6LiaFKR/qJkBSh0uTaFlclrb3qXCunu/lujDZr/JxtppqItkJmHHK Ikod9aUA94RrugMiIzJebTZYhPeN6tg= ARC-Authentication-Results: i=1; imf22.hostedemail.com; dkim=pass header.d=google.com header.s=20230601 header.b=Srq0XYU3; spf=pass (imf22.hostedemail.com: domain of vannapurve@google.com designates 209.85.128.49 as permitted sender) smtp.mailfrom=vannapurve@google.com; dmarc=pass (policy=reject) header.from=google.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1726320859; a=rsa-sha256; cv=none; b=yZAynYGb9BZxVgPcZY6xQraD+MZwg14zG1WKQcedUcDWisnOBeHu2k0z1CEyGJv3fzfLcF 23tBBEv5L+BuDZktfoEV3hzhXBg/U8D2awzFEExoiE8dx4WJAzzMEcP48o8Y7vqHcRmR+S effM0Xg4hwhJ/qr63MwTL8kCeGBdcxY= Received: by mail-wm1-f49.google.com with SMTP id 5b1f17b1804b1-42cae4ead5bso11765e9.1 for ; Sat, 14 Sep 2024 06:34:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1726320888; x=1726925688; darn=kvack.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=dHM/9nGeV0kB5TjHKKHKGDZ6zh5A8DGqa4bFzJrKT/U=; b=Srq0XYU3Ms61cNd6RCGA4ReQ6JECCPUaxqOIoyw5dx061L3vRYN0YdbJKj/ZkCSEH7 Vfa8Q3eZVeiqpuSByhIgsIZzXx4F9ks3jyFXgWudTWWDY9JXJO09mO71R4GrCV1OdLgU cShs8X0wCRY6al4nECF7lPgOfz/Pm8cF4SPEekVlS7guLCS49KjcM7cdkvoDaDxgYwTs tnT+kt+0tQGMWSBxk4rUN1B+X2yTqSKZkwY9eXMjhrpEs6PE8EZsZsD1D9dx0sR4iUys jhv9rtpfDaYpxdgtCIdOH52XcnnzpNIHfX5e1rETh9YGsLd0DI0ROje1nMyQ8xzlsMF+ YeCw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1726320888; x=1726925688; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=dHM/9nGeV0kB5TjHKKHKGDZ6zh5A8DGqa4bFzJrKT/U=; b=ZuxYpjYNvh6XlzGFkZfL/T+iyfSQWtE357BY5CD9Zm+ILwp3oYOULET5Ath5XjNG0H TBuMZiaNSh4eTmtMYLBG0Wh5GrWex111baSOfYtTEDFiMrEbWY0UNvWJw0m1rgyH/ePs zqnQgLlMsjJxafokWJSZ9nljIliETeHl60pIMf9qSBaiTh/qChJCJQFxUDv/mgQrz6CT KKPCnS4IxPeAiG7147+gz65LrSCV9ASkHlD4YNV0y4TydZ1YsafM0c9W0sAoXo6l88om Rgk1Ja+FjTI8SFcvbthiVcoPPSMzXbE9ogUSaFWIC2Irvr9y/TXacovO7EtRWmOvtdnG ZlEQ== X-Forwarded-Encrypted: i=1; AJvYcCXL3Jo8XX2OsJ55VtXe0UsSukPKSvPVAveaAzMaZRHneTqcHFfqfQPHQGPta2fBJ2YH1dMjfhCZBg==@kvack.org X-Gm-Message-State: AOJu0YxefF8Hza665YpRYFORnTf0b5ec74DAFboHdzZ9H7Ztnny6SD74 lG9W7xPFiH+CSP3LV5Q4LdIk7/K3a6KkDWcJZK6u72HmWS6sJ+Hrozxn3QEEgrPG9MnD4OqZyhJ MJAc7JeNv3024+20no4N7ZPH1KfGmUWHtyIm0 X-Google-Smtp-Source: AGHT+IEU9079HmdtThcsiN8JY3iJ1eHKyBPsG+CZSLZMAH2usfwIpF0g9bdh4YwDboVE3ql8z1EaPMYZFS9J2snJ4E8= X-Received: by 2002:a05:600c:1da5:b0:42b:a8fc:3937 with SMTP id 5b1f17b1804b1-42cdcd1ec3amr514975e9.4.1726320887370; Sat, 14 Sep 2024 06:34:47 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Vishal Annapurve Date: Sat, 14 Sep 2024 06:34:36 -0700 Message-ID: Subject: Re: [RFC PATCH 00/39] 1G page support for guest_memfd To: "Du, Fan" Cc: Ackerley Tng , "tabba@google.com" , "quic_eberman@quicinc.com" , "roypat@amazon.co.uk" , "jgg@nvidia.com" , "peterx@redhat.com" , "david@redhat.com" , "rientjes@google.com" , "fvdl@google.com" , "jthoughton@google.com" , "seanjc@google.com" , "pbonzini@redhat.com" , "Li, Zhiquan1" , "Miao, Jun" , "Yamahata, Isaku" , "muchun.song@linux.dev" , "mike.kravetz@oracle.com" , "Aktas, Erdem" , "qperret@google.com" , "jhubbard@nvidia.com" , "willy@infradead.org" , "shuah@kernel.org" , "brauner@kernel.org" , "bfoster@redhat.com" , "kent.overstreet@linux.dev" , "pvorel@suse.cz" , "rppt@kernel.org" , "richard.weiyang@gmail.com" , "anup@brainfault.org" , "Xu, Haibo1" , "ajones@ventanamicro.com" , "vkuznets@redhat.com" , "Wieczor-Retman, Maciej" , "pgonda@google.com" , "oliver.upton@linux.dev" , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "kvm@vger.kernel.org" , "linux-kselftest@vger.kernel.org" , "linux-fsdevel@kvack.org" Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspam-User: X-Stat-Signature: ugt4txn9jngj9yzn4nzt33siibfauaru X-Rspamd-Queue-Id: 2AD57C0007 X-Rspamd-Server: rspam11 X-HE-Tag: 1726320888-267387 X-HE-Meta: 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 VdRaR+S8 GtfOY/N7ic6rgwVUjShTmb0v3ojBtY4O5JsnRIeWBOA6N3L45Ar4PtMrABMM1ibmpB4cgllkizJMzkWIQA6FVR3MWT0/kqDEGOdC1UPIOIVInHtvaAUFafqxyts0j37fGIdyNZxPaZZdmiLJV+zQR6RAbDy4vyuihMDpfeBOQhykrHh72aQc7JyNinr/hSLFSyM0LLDddkIX0eNa5IGUNwIlxpjDTormaNV2UXF09fhhqG6aRNinBHJrj7GR+8dpQlkVJ2Mc8VNpLBae8xxu4Dx5cAaCrfJw9ExRaQX/vPtRIRGhl1aPjT9Fnp4vvRl2kmKVgN3OaZXUnbKENraLuLsGxT1ys7kyev4C/buT+TFjtjrMT4OIHdBiJiJBDeDXpEmDjoCAyb4UDpz7rUk2Y6bvbJcnFVaU39uslRBe+6KbH5XzHuQg0wMhZu70HBs60414GY5uBeAfJXsg= X-Bogosity: Ham, tests=bogofilter, spamicity=0.005119, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, Sep 13, 2024 at 6:08=E2=80=AFPM Du, Fan wrote: > > ... > > > > Hello, > > > > This patchset is our exploration of how to support 1G pages in guest_me= mfd, > > and > > how the pages will be used in Confidential VMs. > > > > The patchset covers: > > > > + How to get 1G pages > > + Allowing mmap() of guest_memfd to userspace so that both private and > > shared > > Hi Ackerley > > Thanks for posting new version :) > > W.r.t above description and below patch snippet from Patch 26-29, > Does this new design aim to backup shared and private GPA with a single > Hugetlb spool which equal VM instance total memory? Yes. > > By my understanding, before this new changes, shared memfd and gmem fd > has dedicate hugetlb pool, that's two copy/reservation of hugetlb spool. Selftests attached to this series use single gmem fd to back guest memory. > > Does Qemu require new changes as well? I'd like to have a test of this se= ries > if you can share Qemu branch? > We are going to discuss this RFC series and related issues at LPC. Once the next steps are finalized, the plan will be to send out an improved version. You can use/modify the selftests that are part of this series to test this feature with software protected VMs for now. Qemu will require changes for this feature on top of already floated gmem integration series [1] that adds software protected VM support to Qemu. If you are interested in testing this feature with TDX VMs then it needs multiple series to set up the right test environment (including [2]). We haven't considered posting Qemu patches and it will be a while before we can get to it. [1] https://patchew.org/QEMU/20230914035117.3285885-1-xiaoyao.li@intel.com/ [2] https://patchwork.kernel.org/project/kvm/cover/20231115071519.2864957-1= -xiaoyao.li@intel.com/