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 X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A066AC10F00 for ; Tue, 19 Feb 2019 09:25:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7AC0821848 for ; Tue, 19 Feb 2019 09:25:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728238AbfBSJZb (ORCPT ); Tue, 19 Feb 2019 04:25:31 -0500 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:42640 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728189AbfBSJZ3 (ORCPT ); Tue, 19 Feb 2019 04:25:29 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 2F4EE1596; Tue, 19 Feb 2019 01:25:25 -0800 (PST) Received: from a075553-lin.blr.arm.com (a075553-lin.blr.arm.com [10.162.0.144]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id E45713F675; Tue, 19 Feb 2019 01:25:15 -0800 (PST) From: Amit Daniel Kachhap To: linux-arm-kernel@lists.infradead.org Cc: Christoffer Dall , Marc Zyngier , Catalin Marinas , Will Deacon , Andrew Jones , Dave Martin , Ramana Radhakrishnan , kvmarm@lists.cs.columbia.edu, Kristina Martsenko , linux-kernel@vger.kernel.org, Amit Daniel Kachhap , Mark Rutland , James Morse , Julien Thierry Subject: [PATCH v6 5/6] arm64/kvm: control accessibility of ptrauth key registers Date: Tue, 19 Feb 2019 14:54:30 +0530 Message-Id: <1550568271-5319-6-git-send-email-amit.kachhap@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1550568271-5319-1-git-send-email-amit.kachhap@arm.com> References: <1550568271-5319-1-git-send-email-amit.kachhap@arm.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org According to userspace settings, ptrauth key registers are conditionally present in guest system register list based on user specified flag KVM_ARM_VCPU_PTRAUTH. Reset routines still sets these registers to default values but they are left like that as they are conditionally accessible (set/get). Signed-off-by: Amit Daniel Kachhap Cc: Mark Rutland Cc: Marc Zyngier Cc: Christoffer Dall Cc: kvmarm@lists.cs.columbia.edu --- This patch needs patch [1] by Dave Martin and adds feature to manage accessibility in a scalable way. [1]: https://lore.kernel.org/linux-arm-kernel/1547757219-19439-13-git-send-email-Dave.Martin@arm.com/ Documentation/arm64/pointer-authentication.txt | 4 ++++ arch/arm64/kvm/sys_regs.c | 7 ++++++- 2 files changed, 10 insertions(+), 1 deletion(-) diff --git a/Documentation/arm64/pointer-authentication.txt b/Documentation/arm64/pointer-authentication.txt index 0529a7d..996e435 100644 --- a/Documentation/arm64/pointer-authentication.txt +++ b/Documentation/arm64/pointer-authentication.txt @@ -87,3 +87,7 @@ created by passing a flag (KVM_ARM_VCPU_PTRAUTH) requesting this feature to be enabled. Without this flag, pointer authentication is not enabled in KVM guests and attempted use of the feature will result in an UNDEFINED exception being injected into the guest. + +Additionally, when KVM_ARM_VCPU_PTRAUTH is not set then KVM will filter +out the Pointer Authentication system key registers from KVM_GET/SET_REG_* +ioctls. diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index f7bcc60..c2f4974 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -1005,8 +1005,13 @@ static bool trap_ptrauth(struct kvm_vcpu *vcpu, return false; } +static bool check_ptrauth(const struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd) +{ + return kvm_arm_vcpu_ptrauth_allowed(vcpu); +} + #define __PTRAUTH_KEY(k) \ - { SYS_DESC(SYS_## k), trap_ptrauth, reset_unknown, k } + { SYS_DESC(SYS_## k), trap_ptrauth, reset_unknown, k , .check_present = check_ptrauth} #define PTRAUTH_KEY(k) \ __PTRAUTH_KEY(k ## KEYLO_EL1), \ -- 2.7.4