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 337B6D6552C for ; Wed, 17 Dec 2025 10:13:48 +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=DqeQsOymv4Y6r+R2NcQcpYtODaHjmHC6q3q+3I6Ph/k=; b=tN2953GKO6PU6fYzFNygjilue8 /57uGU4uOlDALs/H1YhOER48J/Zump2VCZs0oe0TbNNZXFXspt3r3HIMaagEBy7WOf/gnUoccQ7rT HptJn2RC53Jy80eWmKJgynbNS+djWDug0FLtVNXa4iVT/GENsiklsdrk6pkBu6cZ3eg3BtVBPojcP vxDE43PuJgU95f9pRJRwSHY56SKdwwTnJrVDAMMVZL9iHTW69u54diL2dNO7CNGhpcTsFfd0YZmCZ zFXSkNhwNyY0AwzDtXMixqq1SauT2vC7HktXRy7y37Qt8fhMv9LTmDLNDIBn4+YdzJ5fCCpvpS8mY L5mcB1Zw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vVoXP-00000006XRV-0nDq; Wed, 17 Dec 2025 10:13:43 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vVoXF-00000006X7e-43jw for linux-arm-kernel@lists.infradead.org; Wed, 17 Dec 2025 10:13:40 +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 452D7168F; Wed, 17 Dec 2025 02:13:26 -0800 (PST) Received: from e122027.arm.com (unknown [10.57.45.201]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 3CD993F73B; Wed, 17 Dec 2025 02:13:29 -0800 (PST) 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 Subject: [PATCH v12 22/46] arm64: RMI: Create the realm descriptor Date: Wed, 17 Dec 2025 10:10:59 +0000 Message-ID: <20251217101125.91098-23-steven.price@arm.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20251217101125.91098-1-steven.price@arm.com> References: <20251217101125.91098-1-steven.price@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20251217_021334_172741_D807743F X-CRM114-Status: GOOD ( 16.36 ) 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 Creating a realm involves first creating a realm descriptor (RD). This involves passing the configuration information to the RMM. Do this as part of realm_ensure_created() so that the realm is created when it is first needed. Signed-off-by: Steven Price --- New patch for v12 --- arch/arm64/kvm/rmi.c | 117 ++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 115 insertions(+), 2 deletions(-) diff --git a/arch/arm64/kvm/rmi.c b/arch/arm64/kvm/rmi.c index b51e68e56d56..18edc7eeb5fa 100644 --- a/arch/arm64/kvm/rmi.c +++ b/arch/arm64/kvm/rmi.c @@ -500,6 +500,106 @@ static void realm_unmap_shared_range(struct kvm *kvm, start, end); } +/* Calculate the number of s2 root rtts needed */ +static int realm_num_root_rtts(struct realm *realm) +{ + unsigned int ipa_bits = realm->ia_bits; + unsigned int levels = 4 - get_start_level(realm); + unsigned int sl_ipa_bits = levels * (RMM_PAGE_SHIFT - 3) + + RMM_PAGE_SHIFT; + + if (sl_ipa_bits >= ipa_bits) + return 1; + + return 1 << (ipa_bits - sl_ipa_bits); +} + +static int realm_create_rd(struct kvm *kvm) +{ + struct realm *realm = &kvm->arch.realm; + struct realm_params *params = realm->params; + void *rd = NULL; + phys_addr_t rd_phys, params_phys; + size_t pgd_size = kvm_pgtable_stage2_pgd_size(kvm->arch.mmu.vtcr); + int i, r; + int rtt_num_start; + + realm->ia_bits = VTCR_EL2_IPA(kvm->arch.mmu.vtcr); + rtt_num_start = realm_num_root_rtts(realm); + + if (WARN_ON(realm->rd || !realm->params)) + return -EEXIST; + + if (pgd_size / RMM_PAGE_SIZE < rtt_num_start) + return -EINVAL; + + rd = (void *)__get_free_page(GFP_KERNEL); + if (!rd) + return -ENOMEM; + + rd_phys = virt_to_phys(rd); + if (rmi_granule_delegate(rd_phys)) { + r = -ENXIO; + goto free_rd; + } + + for (i = 0; i < pgd_size; i += RMM_PAGE_SIZE) { + phys_addr_t pgd_phys = kvm->arch.mmu.pgd_phys + i; + + if (rmi_granule_delegate(pgd_phys)) { + r = -ENXIO; + goto out_undelegate_tables; + } + } + + params->s2sz = VTCR_EL2_IPA(kvm->arch.mmu.vtcr); + params->rtt_level_start = get_start_level(realm); + params->rtt_num_start = rtt_num_start; + params->rtt_base = kvm->arch.mmu.pgd_phys; + params->vmid = realm->vmid; + + params_phys = virt_to_phys(params); + + if (rmi_realm_create(rd_phys, params_phys)) { + r = -ENXIO; + goto out_undelegate_tables; + } + + if (WARN_ON(rmi_rec_aux_count(rd_phys, &realm->num_aux))) { + WARN_ON(rmi_realm_destroy(rd_phys)); + r = -ENXIO; + goto out_undelegate_tables; + } + + realm->rd = rd; + WRITE_ONCE(realm->state, REALM_STATE_NEW); + /* The realm is up, free the parameters. */ + free_page((unsigned long)realm->params); + realm->params = NULL; + + return 0; + +out_undelegate_tables: + while (i > 0) { + i -= RMM_PAGE_SIZE; + + phys_addr_t pgd_phys = kvm->arch.mmu.pgd_phys + i; + + if (WARN_ON(rmi_granule_undelegate(pgd_phys))) { + /* Leak the pages if they cannot be returned */ + kvm->arch.mmu.pgt = NULL; + break; + } + } + if (WARN_ON(rmi_granule_undelegate(rd_phys))) { + /* Leak the page if it isn't returned */ + return r; + } +free_rd: + free_page((unsigned long)rd); + return r; +} + static int realm_unmap_private_page(struct realm *realm, unsigned long ipa, unsigned long *next_addr) @@ -803,8 +903,21 @@ static int realm_init_ipa_state(struct kvm *kvm, static int realm_ensure_created(struct kvm *kvm) { - /* Provided in later patch */ - return -ENXIO; + int ret; + + switch (kvm_realm_state(kvm)) { + case REALM_STATE_NONE: + break; + case REALM_STATE_NEW: + return 0; + case REALM_STATE_DEAD: + return -ENXIO; + default: + return -EBUSY; + } + + ret = realm_create_rd(kvm); + return ret; } static int set_ripas_of_protected_regions(struct kvm *kvm) -- 2.43.0