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=-8.8 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 5ECCBECDE30 for ; Wed, 17 Oct 2018 10:49:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2EE0121523 for ; Wed, 17 Oct 2018 10:49:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2EE0121523 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727292AbeJQSo0 (ORCPT ); Wed, 17 Oct 2018 14:44:26 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:49674 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726868AbeJQSo0 (ORCPT ); Wed, 17 Oct 2018 14:44:26 -0400 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 A5D561682; Wed, 17 Oct 2018 03:49:18 -0700 (PDT) Received: from a75553-lin.blr.arm.com (unknown [10.162.0.175]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id B50B33F71D; Wed, 17 Oct 2018 03:49:14 -0700 (PDT) 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 Subject: [PATCH v3 6/7] arm64: docs: document KVM support of pointer authentication Date: Wed, 17 Oct 2018 16:17:59 +0530 Message-Id: <1539773280-4159-7-git-send-email-amit.kachhap@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1539773280-4159-1-git-send-email-amit.kachhap@arm.com> References: <1539773280-4159-1-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 The documentation is updated to help in using pointer authentication for KVM guests. Signed-off-by: Amit Daniel Kachhap Cc: Mark Rutland Cc: Christoffer Dall Cc: Marc Zyngier Cc: kvmarm@lists.cs.columbia.edu --- Documentation/arm64/pointer-authentication.txt | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/Documentation/arm64/pointer-authentication.txt b/Documentation/arm64/pointer-authentication.txt index 8a9cb57..b00d735 100644 --- a/Documentation/arm64/pointer-authentication.txt +++ b/Documentation/arm64/pointer-authentication.txt @@ -78,7 +78,13 @@ to TTBR1 addresses (e.g. kernel pointers). Virtualization -------------- -Pointer authentication is not currently supported in KVM guests. KVM +Pointer authentication is enabled in KVM guest when virtual machine is +created by passing a flag requesting this feature to be enabled. Without +this flag, pointer authentication is not enabled in KVM guests and KVM will mask the feature bits from ID_AA64ISAR1_EL1, and attempted use of the feature will result in an UNDEFINED exception being injected into the guest. + +The flag to enable this feature is KVM_ARM_VCPU_PTRAUTH and should be +used in KVM API KVM_ARM_VCPU_INIT. The pointer authentication key +registers are hidden from userspace if this feature is not enabled. -- 2.7.4