From patchwork Wed Jan 29 17:23:18 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fuad Tabba X-Patchwork-Id: 860690 Received: from mail-wm1-f73.google.com (mail-wm1-f73.google.com [209.85.128.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 676481E0DD6 for ; Wed, 29 Jan 2025 17:23:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.73 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738171425; cv=none; b=AaznMh5t0DKfbLno9TC0+cBjJRFTDpSEf+aiVFvVLajADGaGSSukEFPSmK6H8xKkuu2h62kW2Dzyt9Rx2xCpqGN/V2xvwtfRPOa6t+YawDqWMi+ChZHJGgQxSbU8zX0NxvO+BOEnOn8MKQmUXShLb2VKoFqyN4bvclEr5zb/NMY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738171425; c=relaxed/simple; bh=zjFy8tL6ycA9u7oJbIEiNZF5VVWtz8XZQG69IoGVR+I=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=WN1VL+7vt0pfULvSk9GVX66/N9YmFYfbvYlKH3lyoqH/ZQkfokAZzQ/is5UI26D1b+rIIYyPDtxnFdUi4lGcxxLQpcy52+Y0nsTHchMEA1Hp8KbtidS9iG5Ux2cuOEC1eXAzB5rJWohb7sMrJ+STuiyWZzg/Bw//j85WozU4gJQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--tabba.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=CqphjvqB; arc=none smtp.client-ip=209.85.128.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--tabba.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="CqphjvqB" Received: by mail-wm1-f73.google.com with SMTP id 5b1f17b1804b1-43623bf2a83so54989555e9.0 for ; Wed, 29 Jan 2025 09:23:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1738171422; x=1738776222; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=LJ160MXGhYFmROJLbL7eYj3t8ftygUUVZySLs0qAKPY=; b=CqphjvqBG/mlgglSiXD+HWlOvWlpzgEGjsB0f+lu3WknJPYy2S5EV/r24Drq9UDB3c iC27A1JeNRVnD7wtign+DUZEAv9KzUeGnPO7jLaqASTGxmK707OdH06fEnSwumtCVh9U WkEHrNBYOC8f5vRKLP5bBC/OYA8NNig0vulkgqcIukb0y7YzkG9K7uWa2suLgv/U3BSd uv9SwLqLzmMk0o8b4S9Q8MU8R8pcr+FNuzuCRMFEnDswaopZXZQzj1tKK13letyVJwHn C1F8l4RsHQhsm/HyArjhp8wHMQlguMAJN6kA9HDUDU3pxsfz0f2KCf8166QUcMsRkD5f Aesw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1738171422; x=1738776222; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=LJ160MXGhYFmROJLbL7eYj3t8ftygUUVZySLs0qAKPY=; b=G0w2Q0essT6u8xDGwFoy2qLDAs9RGXXKgw/MKH4oAZ+ztwJVi3cnty+fciKR4dTlXV SyDVnda+uyEYuY8IhKc4fq73Gbvic8AkAMNDzc/R95Oq9ivRZ+N1w5zjUSBZEWuW45PG Huk9Z8emWJ6WmP6LeziDyyaidDp77Dnf/bFgEAZwDrDLaZNT3FtrdPTA3VEFCqQmBY/H TLxPvoe/XmAv4P+xLcrOPiB1CVK2rocFvB7JJtVPJ5RVmdSY4U/dNfQ6IjUg2timxSV/ 2u9bFhVAags80s1sW4IQH/8DMmMD+9Z9m8gcisT0Jeh1h3mnzJDMOM6zH2twzm8TAfmm hz0A== X-Forwarded-Encrypted: i=1; AJvYcCXOGPxvQTn7nLcbYfNC3WveYoG9V7e9rrn0q66brzrM69W0EvKVs8ZwUFxuelmk/O9/YEZFNfTB75B8P9Ky@vger.kernel.org X-Gm-Message-State: AOJu0YxezdHJGelNl9a8ElaO7mRxaq2xy8aUG6hUOZ2Bgg0o5DY8DyAf lpphfFbEga0y0OL4TGcpAprk4/Z27N+UsqUaTaTH/vuXzjVhHTejor5J/yR++THwIKcd+6TXOw= = X-Google-Smtp-Source: AGHT+IHzze1fd9XcgYyloPMAtmGdSptsFbtkXMC3i4as+lZ1qQjtORL3JE2QGX7gEDdKOF6yr1lLOcmjHw== X-Received: from wmbg5.prod.google.com ([2002:a05:600c:a405:b0:434:fb78:6216]) (user=tabba job=prod-delivery.src-stubby-dispatcher) by 2002:a05:600c:3b23:b0:436:f960:3428 with SMTP id 5b1f17b1804b1-438dc42ff3cmr36674135e9.29.1738171421994; Wed, 29 Jan 2025 09:23:41 -0800 (PST) Date: Wed, 29 Jan 2025 17:23:18 +0000 In-Reply-To: <20250129172320.950523-1-tabba@google.com> Precedence: bulk X-Mailing-List: linux-arm-msm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250129172320.950523-1-tabba@google.com> X-Mailer: git-send-email 2.48.1.262.g85cc9f2d1e-goog Message-ID: <20250129172320.950523-10-tabba@google.com> Subject: [RFC PATCH v2 09/11] KVM: arm64: Introduce KVM_VM_TYPE_ARM_SW_PROTECTED machine type From: Fuad Tabba To: kvm@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-mm@kvack.org Cc: pbonzini@redhat.com, chenhuacai@kernel.org, mpe@ellerman.id.au, anup@brainfault.org, paul.walmsley@sifive.com, palmer@dabbelt.com, aou@eecs.berkeley.edu, seanjc@google.com, viro@zeniv.linux.org.uk, brauner@kernel.org, willy@infradead.org, akpm@linux-foundation.org, xiaoyao.li@intel.com, yilun.xu@intel.com, chao.p.peng@linux.intel.com, jarkko@kernel.org, amoorthy@google.com, dmatlack@google.com, yu.c.zhang@linux.intel.com, isaku.yamahata@intel.com, mic@digikod.net, vbabka@suse.cz, vannapurve@google.com, ackerleytng@google.com, mail@maciej.szmigiero.name, david@redhat.com, michael.roth@amd.com, wei.w.wang@intel.com, liam.merwick@oracle.com, isaku.yamahata@gmail.com, kirill.shutemov@linux.intel.com, suzuki.poulose@arm.com, steven.price@arm.com, quic_eberman@quicinc.com, quic_mnalajal@quicinc.com, quic_tsoni@quicinc.com, quic_svaddagi@quicinc.com, quic_cvanscha@quicinc.com, quic_pderrin@quicinc.com, quic_pheragu@quicinc.com, catalin.marinas@arm.com, james.morse@arm.com, yuzenghui@huawei.com, oliver.upton@linux.dev, maz@kernel.org, will@kernel.org, qperret@google.com, keirf@google.com, roypat@amazon.co.uk, shuah@kernel.org, hch@infradead.org, jgg@nvidia.com, rientjes@google.com, jhubbard@nvidia.com, fvdl@google.com, hughd@google.com, jthoughton@google.com, tabba@google.com Introduce a new virtual machine type, KVM_VM_TYPE_ARM_SW_PROTECTED, to serve as a development and testing vehicle for Confidential (CoCo) VMs, similar to the x86 KVM_X86_SW_PROTECTED_VM type. Initially, this is used to test guest_memfd without needing any underlying protection. Similar to the x86 type, this is currently only for development and testing. Do not use KVM_VM_TYPE_ARM_SW_PROTECTED for "real" VMs, and especially not in production. The behavior and effective ABI for software-protected VMs is unstable. Signed-off-by: Fuad Tabba --- Documentation/virt/kvm/api.rst | 5 +++++ arch/arm64/include/asm/kvm_host.h | 10 ++++++++++ arch/arm64/kvm/arm.c | 5 +++++ arch/arm64/kvm/mmu.c | 3 --- include/uapi/linux/kvm.h | 6 ++++++ 5 files changed, 26 insertions(+), 3 deletions(-) diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index f15b61317aad..7953b07c8c2b 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -214,6 +214,11 @@ exposed by the guest CPUs in ID_AA64MMFR0_EL1[PARange]. It only affects size of the address translated by the stage2 level (guest physical to host physical address translations). +KVM_VM_TYPE_ARM_SW_PROTECTED is currently only for development and testing of +confidential VMs without having underlying support. Do not use +KVM_VM_TYPE_ARM_SW_PROTECTED for "real" VMs, and especially not in production. +The behavior and effective ABI for software-protected VMs is unstable. + 4.3 KVM_GET_MSR_INDEX_LIST, KVM_GET_MSR_FEATURE_INDEX_LIST ---------------------------------------------------------- diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index e18e9244d17a..e8a0db2ac4fa 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -380,6 +380,8 @@ struct kvm_arch { * the associated pKVM instance in the hypervisor. */ struct kvm_protected_vm pkvm; + + unsigned long vm_type; }; struct kvm_vcpu_fault_info { @@ -1529,4 +1531,12 @@ void kvm_set_vm_id_reg(struct kvm *kvm, u32 reg, u64 val); #define kvm_has_s1poe(k) \ (kvm_has_feat((k), ID_AA64MMFR3_EL1, S1POE, IMP)) +#define kvm_arch_has_private_mem(kvm) \ + (IS_ENABLED(CONFIG_KVM_PRIVATE_MEM) && \ + ((kvm)->arch.vm_type & KVM_VM_TYPE_ARM_SW_PROTECTED)) + +#define kvm_arch_gmem_supports_shared_mem(kvm) \ + (IS_ENABLED(CONFIG_KVM_GMEM_SHARED_MEM) && \ + ((kvm)->arch.vm_type & KVM_VM_TYPE_ARM_SW_PROTECTED)) + #endif /* __ARM64_KVM_HOST_H__ */ diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index a102c3aebdbc..ecdb8db619d8 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -171,6 +171,9 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) { int ret; + if (type & ~KVM_VM_TYPE_MASK) + return -EINVAL; + mutex_init(&kvm->arch.config_lock); #ifdef CONFIG_LOCKDEP @@ -212,6 +215,8 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) bitmap_zero(kvm->arch.vcpu_features, KVM_VCPU_MAX_FEATURES); + kvm->arch.vm_type = type; + return 0; err_free_cpumask: diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index c1f3ddb88cb9..8e19248533f1 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -869,9 +869,6 @@ static int kvm_init_ipa_range(struct kvm_s2_mmu *mmu, unsigned long type) u64 mmfr0, mmfr1; u32 phys_shift; - if (type & ~KVM_VM_TYPE_ARM_IPA_SIZE_MASK) - return -EINVAL; - phys_shift = KVM_VM_TYPE_ARM_IPA_SIZE(type); if (is_protected_kvm_enabled()) { phys_shift = kvm_ipa_limit; diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 3ac805c5abf1..a3973d2b1a69 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -656,6 +656,12 @@ struct kvm_enable_cap { #define KVM_VM_TYPE_ARM_IPA_SIZE_MASK 0xffULL #define KVM_VM_TYPE_ARM_IPA_SIZE(x) \ ((x) & KVM_VM_TYPE_ARM_IPA_SIZE_MASK) + +#define KVM_VM_TYPE_ARM_SW_PROTECTED (1UL << 9) + +#define KVM_VM_TYPE_MASK (KVM_VM_TYPE_ARM_IPA_SIZE_MASK | \ + KVM_VM_TYPE_ARM_SW_PROTECTED) + /* * ioctls for /dev/kvm fds: */