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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id F0CA2CD4F21 for ; Wed, 13 May 2026 13:20:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=Qgp3qybMAhmDcqc5ZtXnGNIIS7hOsX+/EuT7ibNdwo8=; b=uG3vf5Rs6GRHa541ER9to9HIrH Gd8E83IdXBGvXBGoFDRTNdNJ3iPBqQ6ZZdjANx85yHNG+hrjpU/Xkl5uImDDooM9rqjUoDX0T/SCu wqZ2QAjyCZMcv5Gp/NnLqp5aQgWRyfsXgS7jJOSePzd8WY07YEwNnsjVi9TVEGBoTt6rUch08FciH X7oyyPQzXOKDRdkwJAL/OJf73rN1ZS1L+ZPhpNZiWVu9I4DRakrWAlS1KEXdSoYglE+Gk/aL1fqIb Q1dlgSPHC14waNJ9SywIMFr16vBofVRwU2e8SCmJMo46/z0Vuv9dP6krghHzYXDelZTWbhBpansZ7 cfDvghHw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wN9W8-00000002gxI-2Rzl; Wed, 13 May 2026 13:20:52 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wN9Vy-00000002gl2-1HBT for linux-arm-kernel@lists.infradead.org; Wed, 13 May 2026 13:20:50 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 6E8B7302D; Wed, 13 May 2026 06:20:36 -0700 (PDT) Received: from e122027.arm.com (unknown [10.57.68.187]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 1C8563F836; Wed, 13 May 2026 06:20:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1778678441; bh=WXR7vWJwdaWZwjNjucJw2S/umKcmCZUrlHwBjWOcfGE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UUiEVmpRsem4E/KU9uBADYqMzznms3AgjTPEpB5W8eoC1IADOXE86OyO/ObBl4YIf 27dZCEMKsoR2h1JllwxNSs7oXB+hfkLkycYM1IvTVftwJU8q2nfwDh+W6QX7OIrr6c mlszfImT3VaAmY8jPUGpo8NfjSJ08n668OX+Rnkg= From: Steven Price To: kvm@vger.kernel.org, kvmarm@lists.linux.dev Cc: Steven Price , Catalin Marinas , Marc Zyngier , Will Deacon , James Morse , Oliver Upton , Suzuki K Poulose , Zenghui Yu , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Joey Gouly , Alexandru Elisei , Christoffer Dall , Fuad Tabba , linux-coco@lists.linux.dev, Ganapatrao Kulkarni , Gavin Shan , Shanker Donthineni , Alper Gun , "Aneesh Kumar K . V" , Emi Kisanuki , Vishal Annapurve , WeiLin.Chang@arm.com, Lorenzo.Pieralisi2@arm.com Subject: [PATCH v14 26/44] arm64: RMI: Allow populating initial contents Date: Wed, 13 May 2026 14:17:34 +0100 Message-ID: <20260513131757.116630-27-steven.price@arm.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260513131757.116630-1-steven.price@arm.com> References: <20260513131757.116630-1-steven.price@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260513_062042_453911_E100C304 X-CRM114-Status: GOOD ( 19.52 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org The VMM needs to populate the realm with some data before starting (e.g. a kernel and initrd). This is measured by the RMM and used as part of the attestation later on. Signed-off-by: Steven Price --- Changes since v13: * Rename realm_create_protected_data_page() to realm_data_map_init(). Changes since v12: * The ioctl now updates the structure with the amount populated rather than returning this through the ioctl return code. * Use the new RMM v2.0 range based RMI calls. * Adapt to upstream changes in kvm_gmem_populate(). Changes since v11: * The multiplex CAP is gone and there's a new ioctl which makes use of the generic kvm_gmem_populate() functionality. Changes since v7: * Improve the error codes. * Other minor changes from review. Changes since v6: * Handle host potentially having a larger page size than the RMM granule. * Drop historic "par" (protected address range) from populate_par_region() - it doesn't exist within the current architecture. * Add a cond_resched() call in kvm_populate_realm(). Changes since v5: * Refactor to use PFNs rather than tracking struct page in realm_create_protected_data_page(). * Pull changes from a later patch (in the v5 series) for accessing pages from a guest memfd. * Do the populate in chunks to avoid holding locks for too long and triggering RCU stall warnings. --- arch/arm64/include/asm/kvm_rmi.h | 4 ++ arch/arm64/kvm/Kconfig | 1 + arch/arm64/kvm/arm.c | 13 ++++ arch/arm64/kvm/rmi.c | 106 +++++++++++++++++++++++++++++++ 4 files changed, 124 insertions(+) diff --git a/arch/arm64/include/asm/kvm_rmi.h b/arch/arm64/include/asm/kvm_rmi.h index 007249a13dbc..a2b6bc412a22 100644 --- a/arch/arm64/include/asm/kvm_rmi.h +++ b/arch/arm64/include/asm/kvm_rmi.h @@ -88,6 +88,10 @@ int kvm_rec_enter(struct kvm_vcpu *vcpu); int kvm_rec_pre_enter(struct kvm_vcpu *vcpu); int handle_rec_exit(struct kvm_vcpu *vcpu, int rec_run_status); +struct kvm_arm_rmi_populate; + +int kvm_arm_rmi_populate(struct kvm *kvm, + struct kvm_arm_rmi_populate *arg); void kvm_realm_unmap_range(struct kvm *kvm, unsigned long ipa, unsigned long size, diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig index 4e16719fda22..d0cd011cf672 100644 --- a/arch/arm64/kvm/Kconfig +++ b/arch/arm64/kvm/Kconfig @@ -38,6 +38,7 @@ menuconfig KVM select GUEST_PERF_EVENTS if PERF_EVENTS select KVM_GUEST_MEMFD select KVM_GENERIC_MEMORY_ATTRIBUTES + select HAVE_KVM_ARCH_GMEM_POPULATE help Support hosting virtualized guest machines. diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index ed88a203b892..073ba9181da9 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -2131,6 +2131,19 @@ int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) return -EFAULT; return kvm_vm_ioctl_get_reg_writable_masks(kvm, &range); } + case KVM_ARM_RMI_POPULATE: { + struct kvm_arm_rmi_populate req; + int ret; + + if (!kvm_is_realm(kvm)) + return -ENXIO; + if (copy_from_user(&req, argp, sizeof(req))) + return -EFAULT; + ret = kvm_arm_rmi_populate(kvm, &req); + if (copy_to_user(argp, &req, sizeof(req))) + return -EFAULT; + return ret; + } default: return -EINVAL; } diff --git a/arch/arm64/kvm/rmi.c b/arch/arm64/kvm/rmi.c index a89873a5eb77..209087bcf399 100644 --- a/arch/arm64/kvm/rmi.c +++ b/arch/arm64/kvm/rmi.c @@ -486,6 +486,75 @@ void kvm_realm_unmap_range(struct kvm *kvm, unsigned long start, realm_unmap_private_range(kvm, start, end, may_block); } +static int realm_data_map_init(struct kvm *kvm, unsigned long ipa, + kvm_pfn_t dst_pfn, kvm_pfn_t src_pfn, + unsigned long flags) +{ + struct realm *realm = &kvm->arch.realm; + phys_addr_t rd = virt_to_phys(realm->rd); + phys_addr_t dst_phys, src_phys; + int ret; + + dst_phys = __pfn_to_phys(dst_pfn); + src_phys = __pfn_to_phys(src_pfn); + + if (rmi_delegate_page(dst_phys)) + return -ENXIO; + + ret = rmi_rtt_data_map_init(rd, dst_phys, ipa, src_phys, flags); + if (RMI_RETURN_STATUS(ret) == RMI_ERROR_RTT) { + /* Create missing RTTs and retry */ + int level = RMI_RETURN_INDEX(ret); + + KVM_BUG_ON(level == KVM_PGTABLE_LAST_LEVEL, kvm); + + ret = realm_create_rtt_levels(realm, ipa, level, + KVM_PGTABLE_LAST_LEVEL, NULL); + if (!ret) { + ret = rmi_rtt_data_map_init(rd, dst_phys, ipa, src_phys, + flags); + } + } + + if (ret) { + if (WARN_ON(rmi_undelegate_page(dst_phys))) { + /* Undelegate failed, so we leak the page */ + get_page(pfn_to_page(dst_pfn)); + } + } + + return ret; +} + +static int populate_region_cb(struct kvm *kvm, gfn_t gfn, kvm_pfn_t pfn, + struct page *src_page, void *opaque) +{ + unsigned long data_flags = *(unsigned long *)opaque; + phys_addr_t ipa = gfn_to_gpa(gfn); + + if (!src_page) + return -EOPNOTSUPP; + + return realm_data_map_init(kvm, ipa, pfn, page_to_pfn(src_page), + data_flags); +} + +static long populate_region(struct kvm *kvm, + gfn_t base_gfn, + unsigned long pages, + u64 uaddr, + unsigned long data_flags) +{ + long ret = 0; + + mutex_lock(&kvm->slots_lock); + ret = kvm_gmem_populate(kvm, base_gfn, u64_to_user_ptr(uaddr), pages, + populate_region_cb, &data_flags); + mutex_unlock(&kvm->slots_lock); + + return ret; +} + enum ripas_action { RIPAS_INIT, RIPAS_SET, @@ -574,6 +643,43 @@ static int realm_ensure_created(struct kvm *kvm) return -ENXIO; } +int kvm_arm_rmi_populate(struct kvm *kvm, + struct kvm_arm_rmi_populate *args) +{ + unsigned long data_flags = 0; + unsigned long ipa_start = args->base; + unsigned long ipa_end = ipa_start + args->size; + long pages_populated; + int ret; + + if (args->reserved || + (args->flags & ~KVM_ARM_RMI_POPULATE_FLAGS_MEASURE) || + !IS_ALIGNED(ipa_start, PAGE_SIZE) || + !IS_ALIGNED(ipa_end, PAGE_SIZE) || + !IS_ALIGNED(args->source_uaddr, PAGE_SIZE)) + return -EINVAL; + + ret = realm_ensure_created(kvm); + if (ret) + return ret; + + if (args->flags & KVM_ARM_RMI_POPULATE_FLAGS_MEASURE) + data_flags |= RMI_MEASURE_CONTENT; + + pages_populated = populate_region(kvm, gpa_to_gfn(ipa_start), + args->size >> PAGE_SHIFT, + args->source_uaddr, data_flags); + + if (pages_populated < 0) + return pages_populated; + + args->size -= pages_populated << PAGE_SHIFT; + args->source_uaddr += pages_populated << PAGE_SHIFT; + args->base += pages_populated << PAGE_SHIFT; + + return 0; +} + static void kvm_complete_ripas_change(struct kvm_vcpu *vcpu) { struct kvm *kvm = vcpu->kvm; -- 2.43.0