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 A025FC001DB for ; Thu, 3 Aug 2023 19:16:01 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 3A24928029A; Thu, 3 Aug 2023 15:16:01 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 3522628022C; Thu, 3 Aug 2023 15:16:01 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 21B8D28029A; Thu, 3 Aug 2023 15:16:01 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 151BA28022C for ; Thu, 3 Aug 2023 15:16:01 -0400 (EDT) Received: from smtpin08.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id C51D2806D8 for ; Thu, 3 Aug 2023 19:16:00 +0000 (UTC) X-FDA: 81083748480.08.BA06E8A Received: from mail-pg1-f201.google.com (mail-pg1-f201.google.com [209.85.215.201]) by imf28.hostedemail.com (Postfix) with ESMTP id BF8CFC0026 for ; Thu, 3 Aug 2023 19:15:58 +0000 (UTC) Authentication-Results: imf28.hostedemail.com; dkim=pass header.d=google.com header.s=20221208 header.b=DSNF3uKl; spf=pass (imf28.hostedemail.com: domain of 37fzLZAcKCEQglxgtpomuumrk.iusrot03-ssq1giq.uxm@flex--afranji.bounces.google.com designates 209.85.215.201 as permitted sender) smtp.mailfrom=37fzLZAcKCEQglxgtpomuumrk.iusrot03-ssq1giq.uxm@flex--afranji.bounces.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=1691090158; 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=1QAbc+4fCOMN1wq3LOwJ4k1bsXl9R1Q+x4bhgj3rFIg=; b=XcscjkTkS1htGvu11ur5Zm0bEW9S0iZWt1/7p8wIoY1eITUqFFKrz5IA/1S2bFocPZZ/rX ajFYCmhnK5/nmzmkK9bDWwkkAcr7mxXn8jxkmK0hpwNshEg+Pbbt5chJYBAh6Xqw52UYG0 ORaUS1HlOFWSaKCX3YuFLt0MLLbIy6s= ARC-Authentication-Results: i=1; imf28.hostedemail.com; dkim=pass header.d=google.com header.s=20221208 header.b=DSNF3uKl; spf=pass (imf28.hostedemail.com: domain of 37fzLZAcKCEQglxgtpomuumrk.iusrot03-ssq1giq.uxm@flex--afranji.bounces.google.com designates 209.85.215.201 as permitted sender) smtp.mailfrom=37fzLZAcKCEQglxgtpomuumrk.iusrot03-ssq1giq.uxm@flex--afranji.bounces.google.com; dmarc=pass (policy=reject) header.from=google.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1691090158; a=rsa-sha256; cv=none; b=IoEbpXWge/pf76MSzS26BJonIeuDpZOTT/iqNvW/U0T+YZsMnMvUD7kkVXhPm0uoEvGqoX CQe+ShyrQ78bxVRXvwjVAAfu/aKbU+rp0LFmcdfRHZEMiFh+oCCr+fwE2EOFMU4a4idbKm 9VkZTjSrHncfXrQZKb/gaLNuGreiJTI= Received: by mail-pg1-f201.google.com with SMTP id 41be03b00d2f7-564656d952aso873085a12.3 for ; Thu, 03 Aug 2023 12:15:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1691090157; x=1691694957; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=1QAbc+4fCOMN1wq3LOwJ4k1bsXl9R1Q+x4bhgj3rFIg=; b=DSNF3uKlxbN1/j9sGPdV4RLbiLmTPzUp9Zu3X+X+jI/CXp8qoKO4kiLFxh0eWH4ras 3UHMbP1YaoUXHaU6RKc0xiD6OqP0/G8GaXsxhmkMXaXcobPCXbuINlBumVapPQ9eL9WI SQMF6MIyr2Twu3rQpgN63Ty4xEmvWMdFcq1qk0s/bO53R4WtT4D6mxqEq84CrHbE24tW R+R0wb7QBQEWXSd0EQn3phD4GyYVVYig+DH6wM230PxAw/bTqhOS8nPt+LaY5XqmbBEo 2lNVu9E2Fm9D/OSL8FvXxR34+QmBLtfkxeWiU2TVRkIK5+koZ6XE0PUmvWk9wsqvFkyB PpQQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1691090157; x=1691694957; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=1QAbc+4fCOMN1wq3LOwJ4k1bsXl9R1Q+x4bhgj3rFIg=; b=gJ4wTAVENDR+6KCZDXtT0Nc5XF+qJ4bsBXxW/qtsXvlrKLySgpjbahZeDuVVDl6OLU 3lmZ461t+Radw2ZIRNFP8tJSL5yU66xigf+zZkgZVybVgiOHDCAXx/Ui2dd/G41w8v68 7njWMYlzXOY8buVmmuPb3WAl6TQZMItk4wNc8w1HK21w8hypPO/HKwpGfWhgFH6DNqBb TlhL+T7VZOqCrC6dJQBMVphpQbS6pfYDUqZXLZQCcC7TZCg/wg3X4Yh1kHLNNbDEioeO 0xeWgu9pt3x7ZBNNWHOFXV1rvlxnp6ayjrQex0i7/dH+RHf2+hs2o+NB5joUuKLkgq6w EP1Q== X-Gm-Message-State: ABy/qLZokHhtzDmgBOnGRN6NmdDdDlfuTyYtf8h0aVdaYb86N5+knSMj hx1hY7ATIP2TrscLp5Ay9JfylJSUkq1l X-Google-Smtp-Source: APBJJlHtGvcJEMYqDDCqDrlA6FqIV7ZBvnc2RG3ctaXexB6pNXaY+PGUAOnc1N44cMVGOG5WgF6ZzIYHZzSS X-Received: from afranji.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:47f1]) (user=afranji job=sendgmr) by 2002:a63:295a:0:b0:563:5065:9d40 with SMTP id bu26-20020a63295a000000b0056350659d40mr129290pgb.5.1691090157410; Thu, 03 Aug 2023 12:15:57 -0700 (PDT) Date: Thu, 3 Aug 2023 19:15:54 +0000 In-Reply-To: <20230718234512.1690985-13-seanjc@google.com> Mime-Version: 1.0 References: <20230718234512.1690985-13-seanjc@google.com> X-Mailer: git-send-email 2.41.0.640.ga95def55d0-goog Message-ID: <20230803191554.205599-1-afranji@google.com> Subject: Re: [RFC PATCH v11 12/29] KVM: Add KVM_CREATE_GUEST_MEMFD ioctl() for guest-specific backing memory From: Ryan Afranji To: seanjc@google.com Cc: ackerleytng@google.com, akpm@linux-foundation.org, anup@brainfault.org, aou@eecs.berkeley.edu, chao.p.peng@linux.intel.com, chenhuacai@kernel.org, david@redhat.com, isaku.yamahata@gmail.com, jarkko@kernel.org, jmorris@namei.org, kirill.shutemov@linux.intel.com, kvm-riscv@lists.infradead.org, kvm@vger.kernel.org, kvmarm@lists.linux.dev, liam.merwick@oracle.com, linux-arm-kernel@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org, linux-mm@kvack.org, linux-riscv@lists.infradead.org, linux-security-module@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, mail@maciej.szmigiero.name, maz@kernel.org, michael.roth@amd.com, mpe@ellerman.id.au, oliver.upton@linux.dev, palmer@dabbelt.com, paul.walmsley@sifive.com, paul@paul-moore.com, pbonzini@redhat.com, qperret@google.com, serge@hallyn.com, tabba@google.com, vannapurve@google.com, vbabka@suse.cz, wei.w.wang@intel.com, willy@infradead.org, yu.c.zhang@linux.intel.com Content-Type: text/plain; charset="UTF-8" X-Rspamd-Queue-Id: BF8CFC0026 X-Rspam-User: X-Stat-Signature: byzhf5s1arigp9cojry6qmqf9c6apnpx X-Rspamd-Server: rspam01 X-HE-Tag: 1691090158-834328 X-HE-Meta: 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 a0MYvyz3 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 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: > +static struct folio *kvm_gmem_get_folio(struct file *file, pgoff_t index) > +{ > + struct folio *folio; > + > + /* TODO: Support huge pages. */ > + folio = filemap_grab_folio(file->f_mapping, index); > + if (!folio) > + return NULL; In Linux 6.4, filemap_grab_folio() may also return an error value. Instead of just checking for NULL, "IS_ERR_OR_NULL(folio)" will be needed.