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=-17.0 required=3.0 tests=BAYES_00,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 B69E1C4361B for ; Thu, 10 Dec 2020 16:43:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7D48F2388B for ; Thu, 10 Dec 2020 16:43:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391458AbgLJQnm (ORCPT ); Thu, 10 Dec 2020 11:43:42 -0500 Received: from mail.kernel.org ([198.145.29.99]:59892 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2392174AbgLJQBM (ORCPT ); Thu, 10 Dec 2020 11:01:12 -0500 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id F27A123DE5; Thu, 10 Dec 2020 16:00:31 +0000 (UTC) Received: from 78.163-31-62.static.virginmediabusiness.co.uk ([62.31.163.78] helo=why.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94) (envelope-from ) id 1knOMo-0008Di-7P; Thu, 10 Dec 2020 16:00:30 +0000 From: Marc Zyngier To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org Cc: Andre Przywara , Christoffer Dall , Jintack Lim , Alexandru Elisei , James Morse , Julien Thierry , Suzuki K Poulose , kernel-team@android.com Subject: [PATCH v3 02/66] KVM: arm64: nv: Introduce nested virtualization VCPU feature Date: Thu, 10 Dec 2020 15:58:58 +0000 Message-Id: <20201210160002.1407373-3-maz@kernel.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201210160002.1407373-1-maz@kernel.org> References: <20201210160002.1407373-1-maz@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 62.31.163.78 X-SA-Exim-Rcpt-To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, andre.przywara@arm.com, christoffer.dall@arm.com, jintack@cs.columbia.edu, alexandru.elisei@arm.com, james.morse@arm.com, julien.thierry.kdev@gmail.com, suzuki.poulose@arm.com, kernel-team@android.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Christoffer Dall Introduce the feature bit and a primitive that checks if the feature is set behind a static key check based on the cpus_have_const_cap check. Checking nested_virt_in_use() on systems without nested virt enabled should have neglgible overhead. We don't yet allow userspace to actually set this feature. Signed-off-by: Christoffer Dall Signed-off-by: Marc Zyngier --- arch/arm64/include/asm/kvm_nested.h | 14 ++++++++++++++ arch/arm64/include/uapi/asm/kvm.h | 1 + 2 files changed, 15 insertions(+) create mode 100644 arch/arm64/include/asm/kvm_nested.h diff --git a/arch/arm64/include/asm/kvm_nested.h b/arch/arm64/include/asm/kvm_nested.h new file mode 100644 index 000000000000..1028ac65a897 --- /dev/null +++ b/arch/arm64/include/asm/kvm_nested.h @@ -0,0 +1,14 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __ARM64_KVM_NESTED_H +#define __ARM64_KVM_NESTED_H + +#include + +static inline bool nested_virt_in_use(const struct kvm_vcpu *vcpu) +{ + return (!__is_defined(__KVM_NVHE_HYPERVISOR__) && + cpus_have_final_cap(ARM64_HAS_NESTED_VIRT) && + test_bit(KVM_ARM_VCPU_HAS_EL2, vcpu->arch.features)); +} + +#endif /* __ARM64_KVM_NESTED_H */ diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index 24223adae150..fe3cb67f0d26 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -106,6 +106,7 @@ struct kvm_regs { #define KVM_ARM_VCPU_SVE 4 /* enable SVE for this CPU */ #define KVM_ARM_VCPU_PTRAUTH_ADDRESS 5 /* VCPU uses address authentication */ #define KVM_ARM_VCPU_PTRAUTH_GENERIC 6 /* VCPU uses generic authentication */ +#define KVM_ARM_VCPU_HAS_EL2 7 /* Support nested virtualization */ struct kvm_vcpu_init { __u32 target; -- 2.29.2