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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6EF12C433F5 for ; Tue, 2 Nov 2021 00:22:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 58F5D60EDF for ; Tue, 2 Nov 2021 00:22:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232091AbhKBAZR (ORCPT ); Mon, 1 Nov 2021 20:25:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49712 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232097AbhKBAZJ (ORCPT ); Mon, 1 Nov 2021 20:25:09 -0400 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 20BE8C061203 for ; Mon, 1 Nov 2021 17:22:32 -0700 (PDT) Received: by mail-pf1-x44a.google.com with SMTP id w30-20020aa79a1e000000b0048012d2e882so4836891pfj.2 for ; Mon, 01 Nov 2021 17:22:32 -0700 (PDT) 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=Chm/T8yL3ygYrjvri7zfXhNFj/zx6GP1hVE4sMZ+a+w=; b=nN5gKUrFIqzx6CmBSS42DcfwFEpyDsegSFkgJjEQRTH4nwB4hAJbyU1slAbrRmMybH GP7ZzaU7vH0nbVkk0NGjh0fvvwDwguas2GMfEJfWS980D3reVJLje5eQERco2XDriuAD cC5X6GqVWKgR++ugI/Vnoi6YUkr1vqima0lpWMNkq/rcy6mzMjfmeYoq7Mp39T6iQ1gm n+RjTftFmodXfL0ZdpU1lgbAZQRM1F0WxusdGwSMFLbfS3V2aHdcRdA6wcFS9EAE5h8b RE99uIg7ik08KPFXWgW/xyfkOOqknGc1f9/n1/DnojcaJ+dzhxWeytk/l9mLkxF3J+/s +bNw== 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=Chm/T8yL3ygYrjvri7zfXhNFj/zx6GP1hVE4sMZ+a+w=; b=0UK/fEQt/h7Z2GuCrAPJ5EA33vnjf6gLXGYqJrf/IwHesJ3FClWcVGUAtLEoc10eR+ XQ4Z1lZUmVNlHb8gtb1vSbRhvDkD+tXBVqA+S65jCFOAprcSGrisUb/R9rCvW0BLIQ5k M8/eOo3dHjT1fy8qbbOrqCUvGXLRQYisyUGzY5cy1PhM7EcAbd4YDvPyOasQ9ppCTYXA a2HImG15tHeTZ3u4kBHJgG8VuxZgh6tsZ1ejUDd6eNc66vFSe+QgMEXUussqdz2XLHJi RMhJwfYlaSZHz1oIcOTs3JFlV93Mx/eYbaQemHUKpiavOb1oOFNZcnJrACIyN19EwMjj o7Ow== X-Gm-Message-State: AOAM531QAZRKITfoN/IiGgp6LFdOb2zJoW987Qhi2DjqiXGHZ2bX4XZ9 noopWELXQc6wR2GbM5Yrc13PnU+tFC0D X-Google-Smtp-Source: ABdhPJzwWL9vAsGyyzKtoA+qSmHdO5GSQso3+7zYZ8kWXJoBSLwa7gOBkk12voU8VEShgrYWhIwnPdrYS+HE X-Received: from rananta-virt.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:1bcc]) (user=rananta job=sendgmr) by 2002:a17:90b:1c05:: with SMTP id oc5mr2560695pjb.179.1635812551611; Mon, 01 Nov 2021 17:22:31 -0700 (PDT) Date: Tue, 2 Nov 2021 00:21:59 +0000 In-Reply-To: <20211102002203.1046069-1-rananta@google.com> Message-Id: <20211102002203.1046069-5-rananta@google.com> Mime-Version: 1.0 References: <20211102002203.1046069-1-rananta@google.com> X-Mailer: git-send-email 2.33.1.1089.g2158813163f-goog Subject: [RFC PATCH 4/8] KVM: arm64: Add standard hypervisor service calls firmware register From: Raghavendra Rao Ananta To: Marc Zyngier , Andrew Jones , James Morse , Alexandru Elisei , Suzuki K Poulose Cc: Catalin Marinas , Will Deacon , Peter Shier , Ricardo Koller , Oliver Upton , Reiji Watanabe , Jing Zhang , Raghavendra Rao Anata , linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org, kvm@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Introduce the firmware register to hold the standard hypervisor service calls (owner value 5) as a bitmap. The bitmap represents the features that'll be enabled for the guest, as configured by the user-space. Currently, this includes support only for Paravirtualized time, represented by bit-0. Signed-off-by: Raghavendra Rao Ananta --- Documentation/virt/kvm/arm/hypercalls.rst | 23 ++++++++++++++++------- arch/arm64/include/asm/kvm_host.h | 1 + arch/arm64/include/uapi/asm/kvm.h | 6 ++++++ arch/arm64/kvm/arm.c | 1 + arch/arm64/kvm/hypercalls.c | 22 ++++++++++++++++++++++ arch/arm64/kvm/pvtime.c | 3 +++ include/kvm/arm_hypercalls.h | 3 +++ 7 files changed, 52 insertions(+), 7 deletions(-) diff --git a/Documentation/virt/kvm/arm/hypercalls.rst b/Documentation/virt/kvm/arm/hypercalls.rst index 1601919f256d..2cb82c694868 100644 --- a/Documentation/virt/kvm/arm/hypercalls.rst +++ b/Documentation/virt/kvm/arm/hypercalls.rst @@ -20,13 +20,13 @@ pseudo-registers" that can be manipulated using the GET/SET_ONE_REG interface. These registers can be saved/restored by userspace, and set to a convenient value if required. -The firmware register KVM_REG_ARM_STD exposes the hypercall services -in the form of a feature bitmap. Upon VM creation, by default, KVM exposes -all the features to the guest, which can be learnt using GET_ONE_REG -interface. Conversely, the features can be enabled or disabled via the -SET_ONE_REG interface. These registers allow the user-space modification -only until the VM has started running, after which they turn to read-only -registers. SET_ONE_REG in this scenario will return -EBUSY. +The firmware registers, KVM_REG_ARM_STD and KVM_REG_ARM_STD_HYP exposes +the hypercall services in the form of a feature bitmap. Upon VM creation, +by default, KVM exposes all the features to the guest, which can be learnt +using GET_ONE_REG interface. Conversely, the features can be enabled or +disabled via the SET_ONE_REG interface. These registers allow the user-space +modification only until the VM has started running, after which they turn to +read-only registers. SET_ONE_REG in this scenario will return -EBUSY. The following register is defined: @@ -91,4 +91,13 @@ The following register is defined: The bit represents the services offered under v1.0 of ARM True Random Number Generator (TRNG) specification (ARM DEN 0098). +* KVM_REG_ARM_STD_HYP + Controls the bitmap of the ARM Standard Hypervisor Service Calls. + + The following bits are accepted: + + KVM_REG_ARM_STD_HYP_PV_TIME_ST: + The bit represents the Paravirtualized Time service (also known as stolen time) as + represented by ARM DEN0057A. + .. [1] https://developer.arm.com/-/media/developer/pdf/ARM_DEN_0070A_Firmware_interfaces_for_mitigating_CVE-2017-5715.pdf diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 176d6be7b4da..cee4f4b8a756 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -107,6 +107,7 @@ struct hvc_reg_desc { bool write_attempted; u64 kvm_std_bmap; + u64 kvm_std_hyp_bmap; }; struct kvm_arch { diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index 6387dea5396d..46701da1a27d 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -287,6 +287,12 @@ enum kvm_reg_arm_std_bmap { KVM_REG_ARM_STD_BMAP_MAX, }; +#define KVM_REG_ARM_STD_HYP KVM_REG_ARM_FW_REG(4) +enum kvm_reg_arm_std_hyp_bmap { + KVM_REG_ARM_STD_HYP_PV_TIME_ST, + KVM_REG_ARM_STD_HYP_BMAP_MAX, +}; + /* SVE registers */ #define KVM_REG_ARM64_SVE (0x15 << KVM_REG_ARM_COPROC_SHIFT) diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 1cf58aa49222..1c69d2a71b86 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -135,6 +135,7 @@ static void set_default_hypercalls(struct kvm *kvm) struct hvc_reg_desc *hvc_desc = &kvm->arch.hvc_desc; hvc_desc->kvm_std_bmap = ARM_SMCCC_STD_FEATURES; + hvc_desc->kvm_std_hyp_bmap = ARM_SMCCC_STD_HYP_FEATURES; } /** diff --git a/arch/arm64/kvm/hypercalls.c b/arch/arm64/kvm/hypercalls.c index 0b3006353bf6..46064c515058 100644 --- a/arch/arm64/kvm/hypercalls.c +++ b/arch/arm64/kvm/hypercalls.c @@ -65,6 +65,8 @@ static u64 *kvm_fw_reg_to_bmap(struct kvm *kvm, u64 fw_reg) switch (fw_reg) { case KVM_REG_ARM_STD: return &hvc_desc->kvm_std_bmap; + case KVM_REG_ARM_STD_HYP: + return &hvc_desc->kvm_std_hyp_bmap; default: return NULL; } @@ -87,6 +89,10 @@ static const struct kvm_hvc_func_map hvc_std_map[] = { HVC_FUNC_MAP_DESC(ARM_SMCCC_TRNG_RND64, KVM_REG_ARM_STD_TRNG_V1_0), }; +static const struct kvm_hvc_func_map hvc_std_hyp_map[] = { + HVC_FUNC_MAP_DESC(ARM_SMCCC_HV_PV_TIME_ST, KVM_REG_ARM_STD_HYP_PV_TIME_ST), +}; + bool kvm_hvc_call_supported(struct kvm_vcpu *vcpu, u32 func_id) { struct kvm *kvm = vcpu->kvm; @@ -102,6 +108,11 @@ bool kvm_hvc_call_supported(struct kvm_vcpu *vcpu, u32 func_id) hvc_func_map = hvc_std_map; map_sz = ARRAY_SIZE(hvc_std_map); break; + case ARM_SMCCC_OWNER_STANDARD_HYP: + fw_reg = KVM_REG_ARM_STD_HYP; + hvc_func_map = hvc_std_hyp_map; + map_sz = ARRAY_SIZE(hvc_std_hyp_map); + break; default: /* Allow all the owners that aren't mapped */ return true; @@ -218,6 +229,7 @@ static const u64 fw_reg_ids[] = { KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1, KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2, KVM_REG_ARM_STD, + KVM_REG_ARM_STD_HYP, }; int kvm_arm_get_fw_num_regs(struct kvm_vcpu *vcpu) @@ -295,6 +307,9 @@ int kvm_arm_get_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) case KVM_REG_ARM_STD: val = hvc_desc->kvm_std_bmap; break; + case KVM_REG_ARM_STD_HYP: + val = hvc_desc->kvm_std_hyp_bmap; + break; default: return -ENOENT; } @@ -424,6 +439,13 @@ int kvm_arm_set_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) hvc_desc->kvm_std_bmap = val; return 0; + + case KVM_REG_ARM_STD_HYP: + if (val & ~ARM_SMCCC_STD_HYP_FEATURES) + return -EINVAL; + + hvc_desc->kvm_std_hyp_bmap = val; + return 0; default: return -ENOENT; } diff --git a/arch/arm64/kvm/pvtime.c b/arch/arm64/kvm/pvtime.c index 78a09f7a6637..4fa436dbd0b7 100644 --- a/arch/arm64/kvm/pvtime.c +++ b/arch/arm64/kvm/pvtime.c @@ -37,6 +37,9 @@ long kvm_hypercall_pv_features(struct kvm_vcpu *vcpu) u32 feature = smccc_get_arg1(vcpu); long val = SMCCC_RET_NOT_SUPPORTED; + if (!kvm_hvc_call_supported(vcpu, feature)) + return val; + switch (feature) { case ARM_SMCCC_HV_PV_TIME_FEATURES: case ARM_SMCCC_HV_PV_TIME_ST: diff --git a/include/kvm/arm_hypercalls.h b/include/kvm/arm_hypercalls.h index 5f01bb139312..bbb3b12b10e3 100644 --- a/include/kvm/arm_hypercalls.h +++ b/include/kvm/arm_hypercalls.h @@ -9,6 +9,9 @@ #define ARM_SMCCC_STD_FEATURES \ GENMASK_ULL(KVM_REG_ARM_STD_BMAP_MAX - 1, 0) +#define ARM_SMCCC_STD_HYP_FEATURES \ + GENMASK_ULL(KVM_REG_ARM_STD_HYP_BMAP_MAX - 1, 0) + int kvm_hvc_call_handler(struct kvm_vcpu *vcpu); static inline u32 smccc_get_function(struct kvm_vcpu *vcpu) -- 2.33.1.1089.g2158813163f-goog