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 0AB7AD6552C for ; Wed, 17 Dec 2025 10:13:32 +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:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=03feX63v7lpfVYlsSEw1mrqbxb0PzVdnq92152YweXg=; b=DZyV/WoYbB8kOLJRMPgAZF4o5d UU16kUCVUV7r6+txIX6OpIeSeud8g3pw9oYPvwmDro7ZVu3oukN44Wpl3lNc8P7mmuqEtJIIJSL6b Ts977aU7lOrtJLMj1YflWETlYck3Jp24h5Nq11tDqnPmLf2dWMmoxzoLtgAHs9M+9I7ytDb3pHPlo X/xzgkeUK1Af0sALP46LI5OFGOwgSCLBudoLoL5tyI1Gw5VnfKmAqk5vRuFnkNP6y5VH1gbFP1vyn 6s2B6G4OFtijkPEu9mmDxRtlHe1Jr4+C9jCIPhINGlvVqdfZ0U8P/pfnkcH5Q7RRwThVOBdPDdZRK ilX2ldnQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vVoXA-00000006XC5-2QOg; Wed, 17 Dec 2025 10:13:28 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vVoX1-00000006WtJ-19uN for linux-arm-kernel@lists.infradead.org; Wed, 17 Dec 2025 10:13:27 +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 AFD2D1691; Wed, 17 Dec 2025 02:13:11 -0800 (PST) Received: from e122027.arm.com (unknown [10.57.45.201]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 893B13F73B; Wed, 17 Dec 2025 02:13:14 -0800 (PST) From: Steven Price To: kvm@vger.kernel.org, kvmarm@lists.linux.dev Cc: Steven Price , Catalin Marinas , Marc Zyngier , Will Deacon , James Morse , Oliver Upton , Suzuki K Poulose , Zenghui Yu , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Joey Gouly , Alexandru Elisei , Christoffer Dall , Fuad Tabba , linux-coco@lists.linux.dev, Ganapatrao Kulkarni , Gavin Shan , Shanker Donthineni , Alper Gun , "Aneesh Kumar K . V" , Emi Kisanuki , Vishal Annapurve Subject: [PATCH v12 19/46] KVM: arm64: Expose support for private memory Date: Wed, 17 Dec 2025 10:10:56 +0000 Message-ID: <20251217101125.91098-20-steven.price@arm.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20251217101125.91098-1-steven.price@arm.com> References: <20251217101125.91098-1-steven.price@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20251217_021319_461024_6037349E X-CRM114-Status: GOOD ( 10.17 ) 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 Select KVM_GENERIC_MEMORY_ATTRIBUTES and provide the necessary support functions. Signed-off-by: Steven Price --- Changes since v10: * KVM_GENERIC_PRIVATE_MEM replacd with KVM_GENERIC_MEMORY_ATTRIBUTES. Changes since v9: * Drop the #ifdef CONFIG_KVM_PRIVATE_MEM guard from the definition of kvm_arch_has_private_mem() Changes since v2: * Switch kvm_arch_has_private_mem() to a macro to avoid overhead of a function call. * Guard definitions of kvm_arch_{pre,post}_set_memory_attributes() with #ifdef CONFIG_KVM_GENERIC_MEMORY_ATTRIBUTES. * Early out in kvm_arch_post_set_memory_attributes() if the WARN_ON should trigger. --- arch/arm64/include/asm/kvm_host.h | 2 ++ arch/arm64/kvm/Kconfig | 1 + arch/arm64/kvm/mmu.c | 24 ++++++++++++++++++++++++ 3 files changed, 27 insertions(+) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 5a24227088c1..7590d86c78a5 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -1462,6 +1462,8 @@ struct kvm *kvm_arch_alloc_vm(void); #define vcpu_is_protected(vcpu) kvm_vm_is_protected((vcpu)->kvm) +#define kvm_arch_has_private_mem(kvm) ((kvm)->arch.is_realm) + int kvm_arm_vcpu_finalize(struct kvm_vcpu *vcpu, int feature); bool kvm_arm_vcpu_is_finalized(struct kvm_vcpu *vcpu); diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig index 4f803fd1c99a..1cac6dfc0972 100644 --- a/arch/arm64/kvm/Kconfig +++ b/arch/arm64/kvm/Kconfig @@ -38,6 +38,7 @@ menuconfig KVM select SCHED_INFO select GUEST_PERF_EVENTS if PERF_EVENTS select KVM_GUEST_MEMFD + select KVM_GENERIC_MEMORY_ATTRIBUTES help Support hosting virtualized guest machines. diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index cac3d7b73b3d..f2ac01c1de04 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -2503,6 +2503,30 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm, return ret; } +#ifdef CONFIG_KVM_GENERIC_MEMORY_ATTRIBUTES +bool kvm_arch_pre_set_memory_attributes(struct kvm *kvm, + struct kvm_gfn_range *range) +{ + WARN_ON_ONCE(!kvm_arch_has_private_mem(kvm)); + return false; +} + +bool kvm_arch_post_set_memory_attributes(struct kvm *kvm, + struct kvm_gfn_range *range) +{ + if (WARN_ON_ONCE(!kvm_arch_has_private_mem(kvm))) + return false; + + if (range->arg.attributes & KVM_MEMORY_ATTRIBUTE_PRIVATE) + range->attr_filter = KVM_FILTER_SHARED; + else + range->attr_filter = KVM_FILTER_PRIVATE; + kvm_unmap_gfn_range(kvm, range); + + return false; +} +#endif + void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *slot) { } -- 2.43.0