From patchwork Thu Jan 12 19:18:21 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 13098641 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 A9E52C61DB3 for ; Thu, 12 Jan 2023 19:27:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240427AbjALT06 (ORCPT ); Thu, 12 Jan 2023 14:26:58 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49048 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240378AbjALT00 (ORCPT ); Thu, 12 Jan 2023 14:26:26 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B9E375F83 for ; Thu, 12 Jan 2023 11:19:40 -0800 (PST) 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 3B03962169 for ; Thu, 12 Jan 2023 19:19:40 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8FEB4C433F0; Thu, 12 Jan 2023 19:19:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1673551179; bh=caJCdIDxEcs2dm46yIwmQS+/hs5HuoKGvfg5KefJxGc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TUxu4gjv4jgu9KgwxnhEjd3YkD6PSrMD7EPsUs88TOUN7igcKFG48WIM/6cPgilfb j6OQJAMJlQCci18/rebO/G4e1wDGy0SUfnQoRxFcTAlXfDxvK5XMG9RzYWsqH4P9yA aMluxLX4rJjU9IhIyIDRZNNEYiZc3gCxokJqX5gc8gdikpgVHyUD5hJAF6QYdFMz58 69k88BBmFPEcNupGd1WO9vdhJhYmt9N1fDrzvB9DVASVx+LLWkmuuKLen6/vG03eNl 3kVeBGHGHzX2fSJfiTdLRMsswnHoMurVzlRPgN8xmkB07H4Kjq8y1BxHUUnEkgO4Fv nyxWaiFhjYV8w== Received: from sofa.misterjones.org ([185.219.108.64] helo=valley-girl.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1pG36v-001IWu-Iw; Thu, 12 Jan 2023 19:19:37 +0000 From: Marc Zyngier To: kvmarm@lists.linux.dev, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: Alexandru Elisei , Andre Przywara , Chase Conklin , Christoffer Dall , Ganapatrao Kulkarni , Jintack Lim , Russell King , James Morse , Suzuki K Poulose , Oliver Upton , Zenghui Yu Subject: [PATCH v7 02/68] KVM: arm64: nv: Introduce nested virtualization VCPU feature Date: Thu, 12 Jan 2023 19:18:21 +0000 Message-Id: <20230112191927.1814989-3-maz@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230112191927.1814989-1-maz@kernel.org> References: <20230112191927.1814989-1-maz@kernel.org> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: kvmarm@lists.linux.dev, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, alexandru.elisei@arm.com, andre.przywara@arm.com, chase.conklin@arm.com, christoffer.dall@arm.com, gankulkarni@os.amperecomputing.com, jintack@cs.columbia.edu, rmk+kernel@armlinux.org.uk, james.morse@arm.com, suzuki.poulose@arm.com, oliver.upton@linux.dev, yuzenghui@huawei.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 vcpu_has_nv() on systems without nested virt enabled should have negligible overhead. We don't yet allow userspace to actually set this feature. Reviewed-by: Ganapatrao Kulkarni Reviewed-by: Russell King (Oracle) 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..fd601ea68d13 --- /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 vcpu_has_nv(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 a7a857f1784d..f8129c624b07 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -109,6 +109,7 @@ 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;