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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5B0C8C61DD3 for ; Thu, 3 Sep 2026 16:07:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:To:From:Reply-To: Cc:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=1KdsrwciUsa8GH7Ezvv4SZMAWq+rgyKvl6Qg890kKy8=; b=hRBsjBAEkFZA1O+nb0xrUOV1OV I8UrIzS9FKXkjq6rqsZTX0IOlyry3VcALxdPDLROo+9vdY3mUbL3xqSf/O1EOvVXPzKDMpaPmNXIh N6w9kx8aEicHh0syvAt0y4pvSCwK9uLD9JtQFGld/BtVplBFsfPH1/gaMcwsOMuYPNhyfDlOUQW2F JhvqGAcf1ICsEgjBXQjFrFDODh/9cZSrjNqG4gaZgLqKqO0z98BZnHoPNRnrWj/OGNyHs5Gm7vQd4 U/uYETolsb/GE2Zi/LDw09I9gf6eW3AJ1hZ+KetlbRkDCQlc2H7mK4BaQpRAKKm2dw1KkZWdxZDII MRD6zN9A==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1x29xm-000000005C0-3fl7; Thu, 03 Sep 2026 16:06:54 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1x29xi-0000000056o-1ziv for linux-arm-kernel@lists.infradead.org; Thu, 03 Sep 2026 16:06:51 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 3B3861596; Thu, 3 Sep 2026 09:06:46 -0700 (PDT) Received: from e140010.cambridge.arm.com (e140010.arm.com [10.2.213.25]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 341FD3F673; Thu, 3 Sep 2026 09:06:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1788451610; bh=+xEDb1hGKeI2CDY9plNiDwqL5XW3TEtAF0AeP5IGjgE=; h=From:To:Subject:Date:In-Reply-To:References:From; b=UdnnISgS+gVauOkZZq7in3rQtpwKnNkRDWMY2ArbvpO3FnXvU7cLEvXTAGwKcVOUA YsYaemPTLso2h0hcbekRDJZq8sBqcFFqP9VJ03ZTeLAxRrtB4ytziPIh5bRs+P6Ihd CX67ijnv19Gh+ntu0IZzTsm42dmHVHgg6rLocsGQ= From: Alexandru Elisei To: maz@kernel.org, oupton@kernel.org, fuad.tabba@linux.dev, joey.gouly@arm.com, seiden@linux.ibm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, will@kernel.org, mark.rutland@arm.com, linux-perf-users@vger.kernel.org, catalin.marinas@arm.com, james.clark@linaro.org Subject: [RFC PATCH v7 07/28] KVM: arm64: Add KVM_ARM_VCPU_SPE VCPU feature Date: Thu, 3 Sep 2026 17:06:02 +0100 Message-ID: <20260903160623.315525-8-alexandru.elisei@arm.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260903160623.315525-1-alexandru.elisei@arm.com> References: <20260903160623.315525-1-alexandru.elisei@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260903_090650_588588_D166413C X-CRM114-Status: GOOD ( 13.74 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Add a new VCPU feature that enables SPE virtualization when set by userspace. KVM_VCPU_MAX_FEATURE will be bumped and the feature will become selectable by userspace once SPE support in KVM is implemented. Signed-off-by: Alexandru Elisei --- Documentation/virt/kvm/api.rst | 2 ++ arch/arm64/include/asm/kvm_spe.h | 5 +++++ arch/arm64/include/uapi/asm/kvm.h | 1 + arch/arm64/kvm/arm.c | 7 +++++++ 4 files changed, 15 insertions(+) diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index 1ed5c389c7a4..654736fac78c 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -3591,6 +3591,8 @@ Possible features: Depends on KVM_CAP_ARM_EL2_E2H0. KVM_ARM_VCPU_HAS_EL2 must also be set. + - KVM_ARM_VCPU_SPE: Enable SPE for the CPU. Depends on KVM_CAP_ARM_SPE. + 4.83 KVM_ARM_PREFERRED_TARGET ----------------------------- diff --git a/arch/arm64/include/asm/kvm_spe.h b/arch/arm64/include/asm/kvm_spe.h index f05e6d3f5705..e452da82666d 100644 --- a/arch/arm64/include/asm/kvm_spe.h +++ b/arch/arm64/include/asm/kvm_spe.h @@ -8,11 +8,16 @@ #ifdef CONFIG_KVM_ARM_SPE bool kvm_supports_spe(void); + +#define vcpu_has_spe(vcpu) \ + (vcpu_has_feature(vcpu, KVM_ARM_VCPU_SPE)) #else static __always_inline bool kvm_supports_spe(void) { return false; } + +#define vcpu_has_spe(vcpu) false #endif /* CONFIG_KVM_ARM_SPE */ #endif /* __ARM64_KVM_SPE_H__ */ diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index 019e5e3d892e..f7f751c00e6f 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -107,6 +107,7 @@ struct kvm_regs { #define KVM_ARM_VCPU_HAS_EL2 7 /* Support nested virtualization */ #define KVM_ARM_VCPU_HAS_EL2_E2H0 8 /* Limit NV support to E2H RES0 */ #define KVM_ARM_VCPU_PMU_V3_STRICT 9 /* No default PMU creation */ +#define KVM_ARM_VCPU_SPE 10 /* Support SPE in guest */ struct kvm_vcpu_init { __u32 target; diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index eca1184ef9dd..b9cee4cf293d 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1604,6 +1604,9 @@ static unsigned long system_supported_vcpu_features(void) if (!cpus_have_final_cap(ARM64_HAS_NESTED_VIRT)) clear_bit(KVM_ARM_VCPU_HAS_EL2, &features); + if (!kvm_supports_spe()) + clear_bit(KVM_ARM_VCPU_SPE, &features); + return features; } @@ -1648,6 +1651,10 @@ static int kvm_vcpu_init_check_features(struct kvm_vcpu *vcpu, if (test_bit(KVM_ARM_VCPU_HAS_EL2, &features)) return -EINVAL; + /* SPE is incompatible with AArch32 */ + if (test_bit(KVM_ARM_VCPU_SPE, &features)) + return -EINVAL; + return 0; } -- 2.43.0