From patchwork Mon Feb 14 06:57:23 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Reiji Watanabe X-Patchwork-Id: 12745013 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 35C3AC433F5 for ; Mon, 14 Feb 2022 06:59:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240977AbiBNG7R (ORCPT ); Mon, 14 Feb 2022 01:59:17 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:52032 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240970AbiBNG7Q (ORCPT ); Mon, 14 Feb 2022 01:59:16 -0500 Received: from mail-pf1-x44a.google.com (mail-pf1-x44a.google.com [IPv6:2607:f8b0:4864:20::44a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C9C38575F7 for ; Sun, 13 Feb 2022 22:59:08 -0800 (PST) Received: by mail-pf1-x44a.google.com with SMTP id z37-20020a056a001da500b004c74e3fd644so11131946pfw.1 for ; Sun, 13 Feb 2022 22:59:08 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=JUvdV703fUmfdShCFNAQf7aqj0feD90gCaM4pqTWeMQ=; b=AtexfzHv2vR9zcQ70yNlldV96WVg4qjhUTjT/wM+KMso6UOSpbOMAjZUD5mZKYox4/ wkO1MuQcCKnuVCXK7Akw3yDKirDc65s6GqOYJ48YI04tL42gCBb5fviDKFnanzamyOWR 9+p66ZWS5LNMuijwkLmxLVZ5+TJqfbxZn6rmzVc1h9Wn4LAL7sswb+AU2h4n5208GI7C swkrZcF8hQkBb2LDAqFsiqbai7ILrsLsjZORhEk3nNs4ztdUQ07oqjUH9tfW+cY5Q/Hm 8kvFGmzJJV02eOZtdT2+OhEmvfuLK6QIF4hacH7zG27WOPknYueiq5sePt+BMbRbIF7f EPTQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=JUvdV703fUmfdShCFNAQf7aqj0feD90gCaM4pqTWeMQ=; b=nHBNUP90h91kJayMt081OvHzURzj/LbhHVIr0H2+o/zBIZYrgNsa2mg6oKuXP0WIJO 4I7TxOp+/SrI7Nr/uB/crYEi45DnzEP6tZnJElK/JevbeaaZ5LPmqxIFJU0SCXuE0BB2 wlRH9qBqTwzf4X8l2iB8gBXn+PjAL1zd10PvGOXRifl3HKLMb7MeUexzomdSGEoXXktp 9ABnObB5KYDVCLzyovPPd9XPROxWxwEgkkqSuv4QLiX4J/IKaNGo3l5TZIqyPv7ehFl6 H9tEfsUlWEpnXqbe9Lp2fUxBi1U1kBFdxcJ5cx9x4uPRYfz4lv+l0dGOpP3upg+LJDV8 pZxA== X-Gm-Message-State: AOAM5318xk/6odoRc1P6HUAGRLrzcU/by07naWaMZnWuZW1dh71QCDU3 VyuFaHGJH+g3XlZmY8TocQZYpoK09Vk= X-Google-Smtp-Source: ABdhPJyaOpD+2h6EQEPmbCB7T8o9YXhbq3ftyM68EI3CXXoiFBYdusPkULI1OSMibLYdCQMhdod75CutK8k= X-Received: from reiji-vws-sp.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:3d59]) (user=reijiw job=sendgmr) by 2002:a05:6a00:228e:: with SMTP id f14mr13331596pfe.33.1644821948303; Sun, 13 Feb 2022 22:59:08 -0800 (PST) Date: Sun, 13 Feb 2022 22:57:23 -0800 In-Reply-To: <20220214065746.1230608-1-reijiw@google.com> Message-Id: <20220214065746.1230608-5-reijiw@google.com> Mime-Version: 1.0 References: <20220214065746.1230608-1-reijiw@google.com> X-Mailer: git-send-email 2.35.1.265.g69c8d7142f-goog Subject: [PATCH v5 04/27] KVM: arm64: Make ID_AA64PFR0_EL1 writable From: Reiji Watanabe To: Marc Zyngier , kvmarm@lists.cs.columbia.edu Cc: kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, James Morse , Alexandru Elisei , Suzuki K Poulose , Paolo Bonzini , Will Deacon , Andrew Jones , Fuad Tabba , Peng Liang , Peter Shier , Ricardo Koller , Oliver Upton , Jing Zhang , Raghavendra Rao Anata , Reiji Watanabe Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org This patch adds id_reg_info for ID_AA64PFR0_EL1 to make it writable by userspace. Return an error if userspace tries to set SVE/GIC field of the register to a value that conflicts with SVE/GIC configuration for the guest. SIMD/FP/SVE fields of the requested value are validated according to Arm ARM. Signed-off-by: Reiji Watanabe --- arch/arm64/include/asm/sysreg.h | 1 + arch/arm64/kvm/sys_regs.c | 150 +++++++++++++++++++------------- arch/arm64/kvm/vgic/vgic-init.c | 9 ++ 3 files changed, 101 insertions(+), 59 deletions(-) diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h index 3f12e7036985..bfdf32ff5985 100644 --- a/arch/arm64/include/asm/sysreg.h +++ b/arch/arm64/include/asm/sysreg.h @@ -813,6 +813,7 @@ #define ID_AA64PFR0_ASIMD_SUPPORTED 0x0 #define ID_AA64PFR0_ELx_64BIT_ONLY 0x1 #define ID_AA64PFR0_ELx_32BIT_64BIT 0x2 +#define ID_AA64PFR0_GIC3 0x1 /* id_aa64pfr1 */ #define ID_AA64PFR1_MPAMFRAC_SHIFT 16 diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index da76516f2aad..14df7c112e57 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -330,6 +330,93 @@ static void id_reg_info_init(struct id_reg_info *id_reg) id_reg->vcpu_limit_val, val)); } +static int validate_id_aa64pfr0_el1(struct kvm_vcpu *vcpu, + const struct id_reg_info *id_reg, u64 val) +{ + int fp, simd; + unsigned int gic; + bool vcpu_has_sve = vcpu_has_sve(vcpu); + bool pfr0_has_sve = id_aa64pfr0_sve(val); + + simd = cpuid_feature_extract_signed_field(val, ID_AA64PFR0_ASIMD_SHIFT); + fp = cpuid_feature_extract_signed_field(val, ID_AA64PFR0_FP_SHIFT); + /* AdvSIMD field must have the same value as FP field */ + if (simd != fp) + return -EINVAL; + + /* fp must be supported when sve is supported */ + if (pfr0_has_sve && (fp < 0)) + return -EINVAL; + + /* Check if there is a conflict with a request via KVM_ARM_VCPU_INIT */ + if (vcpu_has_sve ^ pfr0_has_sve) + return -EPERM; + + if ((irqchip_in_kernel(vcpu->kvm) && + vcpu->kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3)) { + gic = cpuid_feature_extract_unsigned_field(val, + ID_AA64PFR0_GIC_SHIFT); + if (gic == 0) + return -EPERM; + + if (gic > ID_AA64PFR0_GIC3) + return -E2BIG; + } else { + u64 mask = ARM64_FEATURE_MASK(ID_AA64PFR0_GIC); + int r = arm64_check_features_kvm(id_reg->sys_reg, val & mask, + id_reg->vcpu_limit_val & mask); + if (r) + return r; + } + + return 0; +} + +static void init_id_aa64pfr0_el1_info(struct id_reg_info *id_reg) +{ + u64 limit = id_reg->vcpu_limit_val; + unsigned int gic; + + limit &= ~ARM64_FEATURE_MASK(ID_AA64PFR0_AMU); + if (!system_supports_sve()) + limit &= ~ARM64_FEATURE_MASK(ID_AA64PFR0_SVE); + + /* + * The default is to expose CSV2 == 1 and CSV3 == 1 if the HW + * isn't affected. Userspace can override this as long as it + * doesn't promise the impossible. + */ + limit &= ~(ARM64_FEATURE_MASK(ID_AA64PFR0_CSV2) | + ARM64_FEATURE_MASK(ID_AA64PFR0_CSV3)); + + if (arm64_get_spectre_v2_state() == SPECTRE_UNAFFECTED) + limit |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_CSV2), 1); + if (arm64_get_meltdown_state() == SPECTRE_UNAFFECTED) + limit |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_CSV3), 1); + + gic = cpuid_feature_extract_unsigned_field(limit, ID_AA64PFR0_GIC_SHIFT); + if (gic > 1) { + /* Limit to GICv3.0/4.0 */ + limit &= ~ARM64_FEATURE_MASK(ID_AA64PFR0_GIC); + limit |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_GIC), ID_AA64PFR0_GIC3); + } + id_reg->vcpu_limit_val = limit; +} + +static u64 vcpu_mask_id_aa64pfr0_el1(const struct kvm_vcpu *vcpu, + const struct id_reg_info *idr) +{ + return vcpu_has_sve(vcpu) ? 0 : ARM64_FEATURE_MASK(ID_AA64PFR0_SVE); +} + +static struct id_reg_info id_aa64pfr0_el1_info = { + .sys_reg = SYS_ID_AA64PFR0_EL1, + .ignore_mask = ARM64_FEATURE_MASK(ID_AA64PFR0_GIC), + .init = init_id_aa64pfr0_el1_info, + .validate = validate_id_aa64pfr0_el1, + .vcpu_mask = vcpu_mask_id_aa64pfr0_el1, +}; + /* * An ID register that needs special handling to control the value for the * guest must have its own id_reg_info in id_reg_info_table. @@ -338,7 +425,9 @@ static void id_reg_info_init(struct id_reg_info *id_reg) * validation, etc.) */ #define GET_ID_REG_INFO(id) (id_reg_info_table[IDREG_IDX(id)]) -static struct id_reg_info *id_reg_info_table[KVM_ARM_ID_REG_MAX_NUM] = {}; +static struct id_reg_info *id_reg_info_table[KVM_ARM_ID_REG_MAX_NUM] = { + [IDREG_IDX(SYS_ID_AA64PFR0_EL1)] = &id_aa64pfr0_el1_info, +}; static int validate_id_reg(struct kvm_vcpu *vcpu, u32 id, u64 val) { @@ -1262,20 +1351,6 @@ static u64 __read_id_reg(const struct kvm_vcpu *vcpu, u32 id) val &= ~(id_reg->vcpu_mask(vcpu, id_reg)); switch (id) { - case SYS_ID_AA64PFR0_EL1: - if (!vcpu_has_sve(vcpu)) - val &= ~ARM64_FEATURE_MASK(ID_AA64PFR0_SVE); - val &= ~ARM64_FEATURE_MASK(ID_AA64PFR0_AMU); - val &= ~ARM64_FEATURE_MASK(ID_AA64PFR0_CSV2); - val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_CSV2), (u64)vcpu->kvm->arch.pfr0_csv2); - val &= ~ARM64_FEATURE_MASK(ID_AA64PFR0_CSV3); - val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_CSV3), (u64)vcpu->kvm->arch.pfr0_csv3); - if (irqchip_in_kernel(vcpu->kvm) && - vcpu->kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3) { - val &= ~ARM64_FEATURE_MASK(ID_AA64PFR0_GIC); - val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_GIC), 1); - } - break; case SYS_ID_AA64PFR1_EL1: if (!kvm_has_mte(vcpu->kvm)) val &= ~ARM64_FEATURE_MASK(ID_AA64PFR1_MTE); @@ -1376,48 +1451,6 @@ static unsigned int sve_visibility(const struct kvm_vcpu *vcpu, return REG_HIDDEN; } -static int set_id_aa64pfr0_el1(struct kvm_vcpu *vcpu, - const struct sys_reg_desc *rd, - const struct kvm_one_reg *reg, void __user *uaddr) -{ - const u64 id = sys_reg_to_index(rd); - u8 csv2, csv3; - int err; - u64 val; - - err = reg_from_user(&val, uaddr, id); - if (err) - return err; - - /* - * Allow AA64PFR0_EL1.CSV2 to be set from userspace as long as - * it doesn't promise more than what is actually provided (the - * guest could otherwise be covered in ectoplasmic residue). - */ - csv2 = cpuid_feature_extract_unsigned_field(val, ID_AA64PFR0_CSV2_SHIFT); - if (csv2 > 1 || - (csv2 && arm64_get_spectre_v2_state() != SPECTRE_UNAFFECTED)) - return -EINVAL; - - /* Same thing for CSV3 */ - csv3 = cpuid_feature_extract_unsigned_field(val, ID_AA64PFR0_CSV3_SHIFT); - if (csv3 > 1 || - (csv3 && arm64_get_meltdown_state() != SPECTRE_UNAFFECTED)) - return -EINVAL; - - /* We can only differ with CSV[23], and anything else is an error */ - val ^= read_id_reg(vcpu, rd, false); - val &= ~((0xFUL << ID_AA64PFR0_CSV2_SHIFT) | - (0xFUL << ID_AA64PFR0_CSV3_SHIFT)); - if (val) - return -EINVAL; - - vcpu->kvm->arch.pfr0_csv2 = csv2; - vcpu->kvm->arch.pfr0_csv3 = csv3 ; - - return 0; -} - /* cpufeature ID register user accessors */ static int __get_id_reg(const struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, void __user *uaddr, @@ -1731,8 +1764,7 @@ static const struct sys_reg_desc sys_reg_descs[] = { /* AArch64 ID registers */ /* CRm=4 */ - { SYS_DESC(SYS_ID_AA64PFR0_EL1), .access = access_id_reg, - .get_user = get_id_reg, .set_user = set_id_aa64pfr0_el1, }, + ID_SANITISED(ID_AA64PFR0_EL1), ID_SANITISED(ID_AA64PFR1_EL1), ID_UNALLOCATED(4,2), ID_UNALLOCATED(4,3), diff --git a/arch/arm64/kvm/vgic/vgic-init.c b/arch/arm64/kvm/vgic/vgic-init.c index fc00304fe7d8..f0632b46fbf9 100644 --- a/arch/arm64/kvm/vgic/vgic-init.c +++ b/arch/arm64/kvm/vgic/vgic-init.c @@ -117,6 +117,15 @@ int kvm_vgic_create(struct kvm *kvm, u32 type) else INIT_LIST_HEAD(&kvm->arch.vgic.rd_regions); + if (type == KVM_DEV_TYPE_ARM_VGIC_V3) + /* + * Set ID_AA64PFR0_EL1.GIC to 1. This shouldn't fail unless + * any vCPU in the guest have started. + */ + WARN_ON_ONCE(kvm_set_id_reg_feature(kvm, SYS_ID_AA64PFR0_EL1, + ID_AA64PFR0_GIC3, + ID_AA64PFR0_GIC_SHIFT)); + out_unlock: unlock_all_vcpus(kvm); return ret;