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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 19044C64EC4 for ; Fri, 10 Mar 2023 15:55:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230189AbjCJPzY (ORCPT ); Fri, 10 Mar 2023 10:55:24 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57934 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231359AbjCJPyV (ORCPT ); Fri, 10 Mar 2023 10:54:21 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 2993A5CC31; Fri, 10 Mar 2023 07:47:25 -0800 (PST) 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 7218E1762; Fri, 10 Mar 2023 07:48:08 -0800 (PST) Received: from [10.1.25.11] (e122027.cambridge.arm.com [10.1.25.11]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 7DAAB3FA32; Fri, 10 Mar 2023 07:47:22 -0800 (PST) Message-ID: Date: Fri, 10 Mar 2023 15:47:21 +0000 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.7.1 Subject: Re: [RFC PATCH 06/28] arm64: RME: ioctls to create and configure realms Content-Language: en-GB To: Zhi Wang Cc: kvm@vger.kernel.org, kvmarm@lists.linux.dev, 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 References: <20230127112248.136810-1-suzuki.poulose@arm.com> <20230127112932.38045-1-steven.price@arm.com> <20230127112932.38045-7-steven.price@arm.com> <20230306211015.0000129d@gmail.com> From: Steven Price In-Reply-To: <20230306211015.0000129d@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06/03/2023 19:10, Zhi Wang wrote: > On Fri, 27 Jan 2023 11:29:10 +0000 > Steven Price wrote: > >> Add the KVM_CAP_ARM_RME_CREATE_FD ioctl to create a realm. This involves >> delegating pages to the RMM to hold the Realm Descriptor (RD) and for >> the base level of the Realm Translation Tables (RTT). A VMID also need >> to be picked, since the RMM has a separate VMID address space a >> dedicated allocator is added for this purpose. >> >> KVM_CAP_ARM_RME_CONFIG_REALM is provided to allow configuring the realm >> before it is created. >> >> Signed-off-by: Steven Price >> --- >> arch/arm64/include/asm/kvm_rme.h | 14 ++ >> arch/arm64/kvm/arm.c | 19 ++ >> arch/arm64/kvm/mmu.c | 6 + >> arch/arm64/kvm/reset.c | 33 +++ >> arch/arm64/kvm/rme.c | 357 +++++++++++++++++++++++++++++++ >> 5 files changed, 429 insertions(+) >> >> diff --git a/arch/arm64/include/asm/kvm_rme.h b/arch/arm64/include/asm/kvm_rme.h >> index c26bc2c6770d..055a22accc08 100644 >> --- a/arch/arm64/include/asm/kvm_rme.h >> +++ b/arch/arm64/include/asm/kvm_rme.h >> @@ -6,6 +6,8 @@ >> #ifndef __ASM_KVM_RME_H >> #define __ASM_KVM_RME_H >> >> +#include >> + >> enum realm_state { >> REALM_STATE_NONE, >> REALM_STATE_NEW, >> @@ -15,8 +17,20 @@ enum realm_state { >> >> struct realm { >> enum realm_state state; >> + >> + void *rd; >> + struct realm_params *params; >> + >> + unsigned long num_aux; >> + unsigned int vmid; >> + unsigned int ia_bits; >> }; >> >> int kvm_init_rme(void); >> +u32 kvm_realm_ipa_limit(void); >> + >> +int kvm_realm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap); >> +int kvm_init_realm_vm(struct kvm *kvm); >> +void kvm_destroy_realm(struct kvm *kvm); >> >> #endif >> diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c >> index d97b39d042ab..50f54a63732a 100644 >> --- a/arch/arm64/kvm/arm.c >> +++ b/arch/arm64/kvm/arm.c >> @@ -103,6 +103,13 @@ int kvm_vm_ioctl_enable_cap(struct kvm *kvm, >> r = 0; >> set_bit(KVM_ARCH_FLAG_SYSTEM_SUSPEND_ENABLED, &kvm->arch.flags); >> break; >> + case KVM_CAP_ARM_RME: >> + if (!static_branch_unlikely(&kvm_rme_is_available)) >> + return -EINVAL; >> + mutex_lock(&kvm->lock); >> + r = kvm_realm_enable_cap(kvm, cap); >> + mutex_unlock(&kvm->lock); >> + break; >> default: >> r = -EINVAL; >> break; >> @@ -172,6 +179,13 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) >> */ >> kvm->arch.dfr0_pmuver.imp = kvm_arm_pmu_get_pmuver_limit(); >> >> + /* Initialise the realm bits after the generic bits are enabled */ >> + if (kvm_is_realm(kvm)) { >> + ret = kvm_init_realm_vm(kvm); >> + if (ret) >> + goto err_free_cpumask; >> + } >> + >> return 0; >> >> err_free_cpumask: >> @@ -204,6 +218,8 @@ void kvm_arch_destroy_vm(struct kvm *kvm) >> kvm_destroy_vcpus(kvm); >> >> kvm_unshare_hyp(kvm, kvm + 1); >> + >> + kvm_destroy_realm(kvm); >> } >> >> int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) >> @@ -300,6 +316,9 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) >> case KVM_CAP_ARM_PTRAUTH_GENERIC: >> r = system_has_full_ptr_auth(); >> break; >> + case KVM_CAP_ARM_RME: >> + r = static_key_enabled(&kvm_rme_is_available); >> + break; >> default: >> r = 0; >> } >> diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c >> index 31d7fa4c7c14..d0f707767d05 100644 >> --- a/arch/arm64/kvm/mmu.c >> +++ b/arch/arm64/kvm/mmu.c >> @@ -840,6 +840,12 @@ void kvm_free_stage2_pgd(struct kvm_s2_mmu *mmu) >> struct kvm_pgtable *pgt = NULL; >> >> write_lock(&kvm->mmu_lock); >> + if (kvm_is_realm(kvm) && >> + kvm_realm_state(kvm) != REALM_STATE_DYING) { >> + /* TODO: teardown rtts */ >> + write_unlock(&kvm->mmu_lock); >> + return; >> + } >> pgt = mmu->pgt; >> if (pgt) { >> mmu->pgd_phys = 0; >> diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c >> index e0267f672b8a..c165df174737 100644 >> --- a/arch/arm64/kvm/reset.c >> +++ b/arch/arm64/kvm/reset.c >> @@ -395,3 +395,36 @@ int kvm_set_ipa_limit(void) >> >> return 0; >> } >> + > > The below function doesn't have an user in this patch. Also, > it looks like a part of copy from kvm_init_stage2_mmu() > in arch/arm64/kvm/mmu.c. Good spot ;) Yes I discovered this, it should have been removed - it's no longer used. I think this was an error when I was rebasing: kvm_arm_setup-stage2() was removed in 315775ff7c6d ("KVM: arm64: Consolidate stage-2 initialisation into a single function"). Steve >> +int kvm_arm_setup_stage2(struct kvm *kvm, unsigned long type) >> +{ >> + u64 mmfr0, mmfr1; >> + u32 phys_shift; >> + u32 ipa_limit = kvm_ipa_limit; >> + >> + if (kvm_is_realm(kvm)) >> + ipa_limit = kvm_realm_ipa_limit(); >> + >> + if (type & ~KVM_VM_TYPE_ARM_IPA_SIZE_MASK) >> + return -EINVAL; >> + >> + phys_shift = KVM_VM_TYPE_ARM_IPA_SIZE(type); >> + if (phys_shift) { >> + if (phys_shift > ipa_limit || >> + phys_shift < ARM64_MIN_PARANGE_BITS) >> + return -EINVAL; >> + } else { >> + phys_shift = KVM_PHYS_SHIFT; >> + if (phys_shift > ipa_limit) { >> + pr_warn_once("%s using unsupported default IPA limit, upgrade your VMM\n", >> + current->comm); >> + return -EINVAL; >> + } >> + } >> + >> + mmfr0 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1); >> + mmfr1 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1); >> + kvm->arch.vtcr = kvm_get_vtcr(mmfr0, mmfr1, phys_shift); >> + >> + return 0; >> +} >> diff --git a/arch/arm64/kvm/rme.c b/arch/arm64/kvm/rme.c >> index f6b587bc116e..9f8c5a91b8fc 100644 >> --- a/arch/arm64/kvm/rme.c >> +++ b/arch/arm64/kvm/rme.c >> @@ -5,9 +5,49 @@ >> >> #include >> >> +#include >> +#include >> #include >> #include >> >> +/************ FIXME: Copied from kvm/hyp/pgtable.c **********/ >> +#include >> + >> +struct kvm_pgtable_walk_data { >> + struct kvm_pgtable *pgt; >> + struct kvm_pgtable_walker *walker; >> + >> + u64 addr; >> + u64 end; >> +}; >> + >> +static u32 __kvm_pgd_page_idx(struct kvm_pgtable *pgt, u64 addr) >> +{ >> + u64 shift = kvm_granule_shift(pgt->start_level - 1); /* May underflow */ >> + u64 mask = BIT(pgt->ia_bits) - 1; >> + >> + return (addr & mask) >> shift; >> +} >> + >> +static u32 kvm_pgd_pages(u32 ia_bits, u32 start_level) >> +{ >> + struct kvm_pgtable pgt = { >> + .ia_bits = ia_bits, >> + .start_level = start_level, >> + }; >> + >> + return __kvm_pgd_page_idx(&pgt, -1ULL) + 1; >> +} >> + >> +/******************/ >> + >> +static unsigned long rmm_feat_reg0; >> + >> +static bool rme_supports(unsigned long feature) >> +{ >> + return !!u64_get_bits(rmm_feat_reg0, feature); >> +} >> + >> static int rmi_check_version(void) >> { >> struct arm_smccc_res res; >> @@ -33,8 +73,319 @@ static int rmi_check_version(void) >> return 0; >> } >> >> +static unsigned long create_realm_feat_reg0(struct kvm *kvm) >> +{ >> + unsigned long ia_bits = VTCR_EL2_IPA(kvm->arch.vtcr); >> + u64 feat_reg0 = 0; >> + >> + int num_bps = u64_get_bits(rmm_feat_reg0, >> + RMI_FEATURE_REGISTER_0_NUM_BPS); >> + int num_wps = u64_get_bits(rmm_feat_reg0, >> + RMI_FEATURE_REGISTER_0_NUM_WPS); >> + >> + feat_reg0 |= u64_encode_bits(ia_bits, RMI_FEATURE_REGISTER_0_S2SZ); >> + feat_reg0 |= u64_encode_bits(num_bps, RMI_FEATURE_REGISTER_0_NUM_BPS); >> + feat_reg0 |= u64_encode_bits(num_wps, RMI_FEATURE_REGISTER_0_NUM_WPS); >> + >> + return feat_reg0; >> +} >> + >> +u32 kvm_realm_ipa_limit(void) >> +{ >> + return u64_get_bits(rmm_feat_reg0, RMI_FEATURE_REGISTER_0_S2SZ); >> +} >> + >> +static u32 get_start_level(struct kvm *kvm) >> +{ >> + long sl0 = FIELD_GET(VTCR_EL2_SL0_MASK, kvm->arch.vtcr); >> + >> + return VTCR_EL2_TGRAN_SL0_BASE - sl0; >> +} >> + >> +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; >> + struct kvm_pgtable *pgt = kvm->arch.mmu.pgt; >> + unsigned int pgd_sz; >> + int i, r; >> + >> + if (WARN_ON(realm->rd) || WARN_ON(!realm->params)) >> + return -EEXIST; >> + >> + 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 out; >> + } >> + >> + pgd_sz = kvm_pgd_pages(pgt->ia_bits, pgt->start_level); >> + for (i = 0; i < pgd_sz; i++) { >> + phys_addr_t pgd_phys = kvm->arch.mmu.pgd_phys + i * PAGE_SIZE; >> + >> + if (rmi_granule_delegate(pgd_phys)) { >> + r = -ENXIO; >> + goto out_undelegate_tables; >> + } >> + } >> + >> + params->rtt_level_start = get_start_level(kvm); >> + params->rtt_num_start = pgd_sz; >> + 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; >> + } >> + >> + realm->rd = rd; >> + realm->ia_bits = VTCR_EL2_IPA(kvm->arch.vtcr); >> + >> + if (WARN_ON(rmi_rec_aux_count(rd_phys, &realm->num_aux))) { >> + WARN_ON(rmi_realm_destroy(rd_phys)); >> + goto out_undelegate_tables; >> + } >> + >> + return 0; >> + >> +out_undelegate_tables: >> + while (--i >= 0) { >> + phys_addr_t pgd_phys = kvm->arch.mmu.pgd_phys + i * PAGE_SIZE; >> + >> + WARN_ON(rmi_granule_undelegate(pgd_phys)); >> + } >> + WARN_ON(rmi_granule_undelegate(rd_phys)); >> +out: >> + free_page((unsigned long)rd); >> + return r; >> +} >> + >> +/* Protects access to rme_vmid_bitmap */ >> +static DEFINE_SPINLOCK(rme_vmid_lock); >> +static unsigned long *rme_vmid_bitmap; >> + >> +static int rme_vmid_init(void) >> +{ >> + unsigned int vmid_count = 1 << kvm_get_vmid_bits(); >> + >> + rme_vmid_bitmap = bitmap_zalloc(vmid_count, GFP_KERNEL); >> + if (!rme_vmid_bitmap) { >> + kvm_err("%s: Couldn't allocate rme vmid bitmap\n", __func__); >> + return -ENOMEM; >> + } >> + >> + return 0; >> +} >> + >> +static int rme_vmid_reserve(void) >> +{ >> + int ret; >> + unsigned int vmid_count = 1 << kvm_get_vmid_bits(); >> + >> + spin_lock(&rme_vmid_lock); >> + ret = bitmap_find_free_region(rme_vmid_bitmap, vmid_count, 0); >> + spin_unlock(&rme_vmid_lock); >> + >> + return ret; >> +} >> + >> +static void rme_vmid_release(unsigned int vmid) >> +{ >> + spin_lock(&rme_vmid_lock); >> + bitmap_release_region(rme_vmid_bitmap, vmid, 0); >> + spin_unlock(&rme_vmid_lock); >> +} >> + >> +static int kvm_create_realm(struct kvm *kvm) >> +{ >> + struct realm *realm = &kvm->arch.realm; >> + int ret; >> + >> + if (!kvm_is_realm(kvm) || kvm_realm_state(kvm) != REALM_STATE_NONE) >> + return -EEXIST; >> + >> + ret = rme_vmid_reserve(); >> + if (ret < 0) >> + return ret; >> + realm->vmid = ret; >> + >> + ret = realm_create_rd(kvm); >> + if (ret) { >> + rme_vmid_release(realm->vmid); >> + return ret; >> + } >> + >> + 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; >> +} >> + >> +static int config_realm_hash_algo(struct realm *realm, >> + struct kvm_cap_arm_rme_config_item *cfg) >> +{ >> + switch (cfg->hash_algo) { >> + case KVM_CAP_ARM_RME_MEASUREMENT_ALGO_SHA256: >> + if (!rme_supports(RMI_FEATURE_REGISTER_0_HASH_SHA_256)) >> + return -EINVAL; >> + break; >> + case KVM_CAP_ARM_RME_MEASUREMENT_ALGO_SHA512: >> + if (!rme_supports(RMI_FEATURE_REGISTER_0_HASH_SHA_512)) >> + return -EINVAL; >> + break; >> + default: >> + return -EINVAL; >> + } >> + realm->params->measurement_algo = cfg->hash_algo; >> + return 0; >> +} >> + >> +static int config_realm_sve(struct realm *realm, >> + struct kvm_cap_arm_rme_config_item *cfg) >> +{ >> + u64 features_0 = realm->params->features_0; >> + int max_sve_vq = u64_get_bits(rmm_feat_reg0, >> + RMI_FEATURE_REGISTER_0_SVE_VL); >> + >> + if (!rme_supports(RMI_FEATURE_REGISTER_0_SVE_EN)) >> + return -EINVAL; >> + >> + if (cfg->sve_vq > max_sve_vq) >> + return -EINVAL; >> + >> + features_0 &= ~(RMI_FEATURE_REGISTER_0_SVE_EN | >> + RMI_FEATURE_REGISTER_0_SVE_VL); >> + features_0 |= u64_encode_bits(1, RMI_FEATURE_REGISTER_0_SVE_EN); >> + features_0 |= u64_encode_bits(cfg->sve_vq, >> + RMI_FEATURE_REGISTER_0_SVE_VL); >> + >> + realm->params->features_0 = features_0; >> + return 0; >> +} >> + >> +static int kvm_rme_config_realm(struct kvm *kvm, struct kvm_enable_cap *cap) >> +{ >> + struct kvm_cap_arm_rme_config_item cfg; >> + struct realm *realm = &kvm->arch.realm; >> + int r = 0; >> + >> + if (kvm_realm_state(kvm) != REALM_STATE_NONE) >> + return -EBUSY; >> + >> + if (copy_from_user(&cfg, (void __user *)cap->args[1], sizeof(cfg))) >> + return -EFAULT; >> + >> + switch (cfg.cfg) { >> + case KVM_CAP_ARM_RME_CFG_RPV: >> + memcpy(&realm->params->rpv, &cfg.rpv, sizeof(cfg.rpv)); >> + break; >> + case KVM_CAP_ARM_RME_CFG_HASH_ALGO: >> + r = config_realm_hash_algo(realm, &cfg); >> + break; >> + case KVM_CAP_ARM_RME_CFG_SVE: >> + r = config_realm_sve(realm, &cfg); >> + break; >> + default: >> + r = -EINVAL; >> + } >> + >> + return r; >> +} >> + >> +int kvm_realm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap) >> +{ >> + int r = 0; >> + >> + switch (cap->args[0]) { >> + case KVM_CAP_ARM_RME_CONFIG_REALM: >> + r = kvm_rme_config_realm(kvm, cap); >> + break; >> + case KVM_CAP_ARM_RME_CREATE_RD: >> + if (kvm->created_vcpus) { >> + r = -EBUSY; >> + break; >> + } >> + >> + r = kvm_create_realm(kvm); >> + break; >> + default: >> + r = -EINVAL; >> + break; >> + } >> + >> + return r; >> +} >> + >> +void kvm_destroy_realm(struct kvm *kvm) >> +{ >> + struct realm *realm = &kvm->arch.realm; >> + struct kvm_pgtable *pgt = kvm->arch.mmu.pgt; >> + unsigned int pgd_sz; >> + int i; >> + >> + if (realm->params) { >> + free_page((unsigned long)realm->params); >> + realm->params = NULL; >> + } >> + >> + if (kvm_realm_state(kvm) == REALM_STATE_NONE) >> + return; >> + >> + WRITE_ONCE(realm->state, REALM_STATE_DYING); >> + >> + rme_vmid_release(realm->vmid); >> + >> + if (realm->rd) { >> + phys_addr_t rd_phys = virt_to_phys(realm->rd); >> + >> + if (WARN_ON(rmi_realm_destroy(rd_phys))) >> + return; >> + if (WARN_ON(rmi_granule_undelegate(rd_phys))) >> + return; >> + free_page((unsigned long)realm->rd); >> + realm->rd = NULL; >> + } >> + >> + pgd_sz = kvm_pgd_pages(pgt->ia_bits, pgt->start_level); >> + for (i = 0; i < pgd_sz; i++) { >> + phys_addr_t pgd_phys = kvm->arch.mmu.pgd_phys + i * PAGE_SIZE; >> + >> + if (WARN_ON(rmi_granule_undelegate(pgd_phys))) >> + return; >> + } >> + >> + kvm_free_stage2_pgd(&kvm->arch.mmu); >> +} >> + >> +int kvm_init_realm_vm(struct kvm *kvm) >> +{ >> + struct realm_params *params; >> + >> + params = (struct realm_params *)get_zeroed_page(GFP_KERNEL); >> + if (!params) >> + return -ENOMEM; >> + >> + params->features_0 = create_realm_feat_reg0(kvm); >> + kvm->arch.realm.params = params; >> + return 0; >> +} >> + >> int kvm_init_rme(void) >> { >> + int ret; >> + >> if (PAGE_SIZE != SZ_4K) >> /* Only 4k page size on the host is supported */ >> return 0; >> @@ -43,6 +394,12 @@ int kvm_init_rme(void) >> /* Continue without realm support */ >> return 0; >> >> + ret = rme_vmid_init(); >> + if (ret) >> + return ret; >> + >> + WARN_ON(rmi_features(0, &rmm_feat_reg0)); >> + >> /* Future patch will enable static branch kvm_rme_is_available */ >> >> return 0; >