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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 77EBAC6FD18 for ; Tue, 18 Apr 2023 12:44:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231944AbjDRMoo (ORCPT ); Tue, 18 Apr 2023 08:44:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34484 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231945AbjDRMon (ORCPT ); Tue, 18 Apr 2023 08:44:43 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 43B18167C2 for ; Tue, 18 Apr 2023 05:44:42 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id C64A963374 for ; Tue, 18 Apr 2023 12:44:41 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D83ABC433D2; Tue, 18 Apr 2023 12:44:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1681821881; bh=mSsL7HZGPx3DaCzUaCYeDawLRizkN8o1Fw+ubaHMdhQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=D3Fqj58yHkZkZJeHFD4CzKNoYWfHDqbC7GJw3ooWcaRD7kc//usNvnwakTjm6facJ m4xywCCASioQMpIC3gbyEJ/N3/GP4jAbfZOCLUFsAK8Y52EI9DIseAeP55eoDWCbtj R1yKoSiQshMEX+mdwOnvS9UbnB7+T+lhnVqdfdNo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Fuad Tabba , Oliver Upton , Sasha Levin Subject: [PATCH 6.1 047/134] KVM: arm64: Advertise ID_AA64PFR0_EL1.CSV2/3 to protected VMs Date: Tue, 18 Apr 2023 14:21:43 +0200 Message-Id: <20230418120314.570071134@linuxfoundation.org> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230418120313.001025904@linuxfoundation.org> References: <20230418120313.001025904@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Fuad Tabba [ Upstream commit e81625218bf7986ba1351a98c43d346b15601d26 ] The existing pKVM code attempts to advertise CSV2/3 using values initialized to 0, but never set. To advertise CSV2/3 to protected guests, pass the CSV2/3 values to hyp when initializing hyp's view of guests' ID_AA64PFR0_EL1. Similar to non-protected KVM, these are system-wide, rather than per cpu, for simplicity. Fixes: 6c30bfb18d0b ("KVM: arm64: Add handlers for protected VM System Registers") Signed-off-by: Fuad Tabba Link: https://lore.kernel.org/r/20230404152321.413064-1-tabba@google.com Signed-off-by: Oliver Upton Signed-off-by: Sasha Levin --- arch/arm64/kvm/arm.c | 26 ++++++++++++++++++- .../arm64/kvm/hyp/include/nvhe/fixed_config.h | 5 +++- arch/arm64/kvm/hyp/nvhe/sys_regs.c | 7 ----- 3 files changed, 29 insertions(+), 9 deletions(-) diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index e40606a560997..6ce6888cf73d6 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1870,9 +1870,33 @@ static int do_pkvm_init(u32 hyp_va_bits) return ret; } +static u64 get_hyp_id_aa64pfr0_el1(void) +{ + /* + * Track whether the system isn't affected by spectre/meltdown in the + * hypervisor's view of id_aa64pfr0_el1, used for protected VMs. + * Although this is per-CPU, we make it global for simplicity, e.g., not + * to have to worry about vcpu migration. + * + * Unlike for non-protected VMs, userspace cannot override this for + * protected VMs. + */ + u64 val = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1); + + val &= ~(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2) | + ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3)); + + val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2), + arm64_get_spectre_v2_state() == SPECTRE_UNAFFECTED); + val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3), + arm64_get_meltdown_state() == SPECTRE_UNAFFECTED); + + return val; +} + static void kvm_hyp_init_symbols(void) { - kvm_nvhe_sym(id_aa64pfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1); + kvm_nvhe_sym(id_aa64pfr0_el1_sys_val) = get_hyp_id_aa64pfr0_el1(); kvm_nvhe_sym(id_aa64pfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1); kvm_nvhe_sym(id_aa64isar0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR0_EL1); kvm_nvhe_sym(id_aa64isar1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR1_EL1); diff --git a/arch/arm64/kvm/hyp/include/nvhe/fixed_config.h b/arch/arm64/kvm/hyp/include/nvhe/fixed_config.h index 07edfc7524c94..37440e1dda930 100644 --- a/arch/arm64/kvm/hyp/include/nvhe/fixed_config.h +++ b/arch/arm64/kvm/hyp/include/nvhe/fixed_config.h @@ -33,11 +33,14 @@ * Allow for protected VMs: * - Floating-point and Advanced SIMD * - Data Independent Timing + * - Spectre/Meltdown Mitigation */ #define PVM_ID_AA64PFR0_ALLOW (\ ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_FP) | \ ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_AdvSIMD) | \ - ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_DIT) \ + ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_DIT) | \ + ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2) | \ + ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3) \ ) /* diff --git a/arch/arm64/kvm/hyp/nvhe/sys_regs.c b/arch/arm64/kvm/hyp/nvhe/sys_regs.c index 0f9ac25afdf40..3d5121ee39777 100644 --- a/arch/arm64/kvm/hyp/nvhe/sys_regs.c +++ b/arch/arm64/kvm/hyp/nvhe/sys_regs.c @@ -84,19 +84,12 @@ static u64 get_restricted_features_unsigned(u64 sys_reg_val, static u64 get_pvm_id_aa64pfr0(const struct kvm_vcpu *vcpu) { - const struct kvm *kvm = (const struct kvm *)kern_hyp_va(vcpu->kvm); u64 set_mask = 0; u64 allow_mask = PVM_ID_AA64PFR0_ALLOW; set_mask |= get_restricted_features_unsigned(id_aa64pfr0_el1_sys_val, PVM_ID_AA64PFR0_RESTRICT_UNSIGNED); - /* Spectre and Meltdown mitigation in KVM */ - set_mask |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2), - (u64)kvm->arch.pfr0_csv2); - set_mask |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3), - (u64)kvm->arch.pfr0_csv3); - return (id_aa64pfr0_el1_sys_val & allow_mask) | set_mask; } -- 2.39.2