From patchwork Tue Feb 11 17:48:07 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 11376131 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E8A521395 for ; Tue, 11 Feb 2020 17:50:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C7EFF20661 for ; Tue, 11 Feb 2020 17:50:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581443411; bh=Q45nUi+j7GZ+5bZdrZa7v6bmgIUXdcImPx3jSm4b5vM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=V2312moLqW2s8yct6Mwbmy9m/z8ojnLqLuAXMMXtnngHA8dKJMejnPZfKbnPNin/q sfQW1KF3f6d9HJZX/RgJT2itK/DkQtZdtX1VViTNuTcSiFJEoC9tfipF1LzOIRpigU YDwQiV2dCtoUvje2TDlGKZ4ac+ZYFOaXVT1yiNVA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729989AbgBKRt6 (ORCPT ); Tue, 11 Feb 2020 12:49:58 -0500 Received: from mail.kernel.org ([198.145.29.99]:52302 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728601AbgBKRt5 (ORCPT ); Tue, 11 Feb 2020 12:49:57 -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 4EA22206D7; Tue, 11 Feb 2020 17:49:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581443397; bh=Q45nUi+j7GZ+5bZdrZa7v6bmgIUXdcImPx3jSm4b5vM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lfg5GWl4io9VLVhsodj2YrfEPfxCT8wxzicuO2HOuuR2HtyajJsr6Uy+4JQbEh9m4 eXKqTRDVxGF2V58s9HzxO+UwIlOSGkcj3cG1E9n7v8Px9aHC6xhGLy+4E0Rb9+Jjcw k3HvM6YOQWR84p+7vpV9Z0cxWcCqmzGOCL5N6z+s= 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:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1j1ZfX-004O7k-Ip; Tue, 11 Feb 2020 17:49:55 +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 , Dave Martin , Jintack Lim , Alexandru Elisei , James Morse , Julien Thierry , Suzuki K Poulose Subject: [PATCH v2 03/94] KVM: arm64: nv: Introduce nested virtualization VCPU feature Date: Tue, 11 Feb 2020 17:48:07 +0000 Message-Id: <20200211174938.27809-4-maz@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200211174938.27809-1-maz@kernel.org> References: <20200211174938.27809-1-maz@kernel.org> MIME-Version: 1.0 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, Dave.Martin@arm.com, jintack@cs.columbia.edu, alexandru.elisei@arm.com, james.morse@arm.com, julien.thierry.kdev@gmail.com, suzuki.poulose@arm.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Sender: kvm-owner@vger.kernel.org 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/arm/include/asm/kvm_nested.h | 9 +++++++++ arch/arm64/include/asm/kvm_nested.h | 13 +++++++++++++ arch/arm64/include/uapi/asm/kvm.h | 1 + 3 files changed, 23 insertions(+) create mode 100644 arch/arm/include/asm/kvm_nested.h create mode 100644 arch/arm64/include/asm/kvm_nested.h diff --git a/arch/arm/include/asm/kvm_nested.h b/arch/arm/include/asm/kvm_nested.h new file mode 100644 index 000000000000..124ff6445f8f --- /dev/null +++ b/arch/arm/include/asm/kvm_nested.h @@ -0,0 +1,9 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __ARM_KVM_NESTED_H +#define __ARM_KVM_NESTED_H + +#include + +static inline bool nested_virt_in_use(const struct kvm_vcpu *vcpu) { return false; } + +#endif /* __ARM_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..f243a8acb9fc --- /dev/null +++ b/arch/arm64/include/asm/kvm_nested.h @@ -0,0 +1,13 @@ +/* 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 cpus_have_const_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 ba85bb23f060..5b9c58a55537 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;