From patchwork Mon Mar 18 23:33:37 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paolo Bonzini X-Patchwork-Id: 13596029 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5125C60EC7 for ; Mon, 18 Mar 2024 23:34:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710804851; cv=none; b=oISr7O6PKwyzgDSx2s8Iwu8X0FCEIF/JxkYj4BWbJAbVUdHXlKX1Aa++sB0WwLdfWDvgFCtnwmFCuIKlPHwufrargyICf+IZYKFiwsKU3560fJ3nk2Vkic4rQyXKWdAYN67nbEKAMHVAKTe9q4BjQviy2NDXUBFeLSFHJ/bolas= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710804851; c=relaxed/simple; bh=O8d8bKZo5siR8MieahkhVmdD32+jITrspI0Yw6jg/sg=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=tmRPuWdRp9/Lfdwc9p6PauvXoTyaThXA+yLtbbjQwwSUZWOxSKzSG96BaMUCDY8bOg0UesRlVzfk1xe4IqeXfoTaB6UyUpTdoIgQYDK/r98JBcYrlnGDZEQmT7LfoUj/FmFjpTQfxxurVdBXbSFiX6p44II2sPb13U2+//OqGM8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=SyQAbhTB; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="SyQAbhTB" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1710804847; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=Df3YFTKjtHSFy1h833T/9wNhgRF6OQfT8JsQ4nzMHO4=; b=SyQAbhTBHa5Q+15iEGMhRUBN2nHO/Z//6ryWqbVnjYjTMOhpKNaSPBBu/DX076sWrSJVm8 DpGV3WYLRFzL1w3+7Q1oz3fvfq9qBSN8Uexkeg7KS5lq/dy57y4hvPozwXQV/V+eARMRjh uJ4aB6LhYsc6Mnupq1mXdSFM5V4Bwu4= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-470-bokCas9LPf2LDOxss9HlNg-1; Mon, 18 Mar 2024 19:33:54 -0400 X-MC-Unique: bokCas9LPf2LDOxss9HlNg-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 9EAA0811E81; Mon, 18 Mar 2024 23:33:53 +0000 (UTC) Received: from virtlab701.virt.lab.eng.bos.redhat.com (virtlab701.virt.lab.eng.bos.redhat.com [10.19.152.228]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4AD1B1121312; Mon, 18 Mar 2024 23:33:53 +0000 (UTC) From: Paolo Bonzini To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: michael.roth@amd.com, isaku.yamahata@intel.com, seanjc@google.com, Dave Hansen Subject: [PATCH v4 00/15] KVM: SEV: allow customizing VMSA features Date: Mon, 18 Mar 2024 19:33:37 -0400 Message-ID: <20240318233352.2728327-1-pbonzini@redhat.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.3 [Dave: there is a small arch/x86/kernel/fpu change in patch 9; I am CCing you in the cover letter just for context. - Paolo] The idea that no parameter would ever be necessary when enabling SEV or SEV-ES for a VM was decidedly optimistic. The first source of variability that was encountered is the desired set of VMSA features, as that affects the measurement of the VM's initial state and cannot be changed arbitrarily by the hypervisor. This series adds all the APIs that are needed to customize the features, with room for future enhancements: - a new /dev/kvm device attribute to retrieve the set of supported features (right now, only debug swap) - a new sub-operation for KVM_MEM_ENCRYPT_OP that can take a struct, replacing the existing KVM_SEV_INIT and KVM_SEV_ES_INIT It then puts the new op to work by including the VMSA features as a field of the The existing KVM_SEV_INIT and KVM_SEV_ES_INIT use the full set of supported VMSA features for backwards compatibility; but I am considering also making them use zero as the feature mask, and will gladly adjust the patches if so requested. In order to avoid creating *two* new KVM_MEM_ENCRYPT_OPs, I decided that I could as well make SEV and SEV-ES use VM types. And then, why not make a SEV-ES VM, when created with the new VM type instead of KVM_SEV_ES_INIT, reject KVM_GET_REGS/KVM_SET_REGS and friends on the vCPU file descriptor once the VMSA has been encrypted... Which is how the API should have always behaved. Note: despite having the same number of patches as v3, #9 and #15 are new! The series is structured as follows: - patches 1 and 2 change sev.c so that it is compiled only if SEV is enabled in kconfig - patches 3 to 6 introduce the new device attribute to retrieve supported VMSA features - patches 7 and 8 introduce new infrastructure for VM types, replacing the similar code in the TDX patches - patch 9 allows setting the FPU and AVX state prior to encryption of the VMSA - patches 10 to 12 introduce the new VM types for SEV and SEV-ES, and KVM_SEV_INIT2 as a new sub-operation for KVM_MEM_ENCRYPT_OP. - patch 13 reenables DebugSwap, now that there is an API that allows doing so without breaking backwards compatibility - patches 14 and 15 test the new ioctl. The idea is that SEV SNP will only ever support KVM_SEV_INIT2. I have placed patches for QEMU to support this new API at branch sevinit2 of https://gitlab.com/bonzini/qemu. I haven't fully tested patch 9 and it really deserves a selftest, it is a bit tricky though without ucall infrastructure for SEV. I will look at it tomorrow. The series is at branch kvm-coco-queue of kvm.git, and I would like to include it in kvm/next as soon as possible after the release of -rc1. Thanks, Paolo v3->v4: - moved patches 1 and 5 to separate "fixes" series for 6.9 - do not conditionalize prototypes for functions that are called by common SVM code - rebased on top of SEV selftest infrastructure from 6.9 merge window; include new patch to drop the "subtype" concept - rebased on top of SEV-SNP patches from 6.9 merge window - rebased on top of patch to disable DebugSwap from 6.8 rc; drop "warn" once SEV_ES_INIT stops enabling VMSA features and finally re-enable DebugSwap - simplified logic to return -EINVAL from ioctls - also block KVM_GET/SET_FPU for protected-state guests - move logic to set kvm_>arch.has_protected_state to svm_vm_init - fix "struct struct" in documentation Paolo Bonzini (14): KVM: SVM: Compile sev.c if and only if CONFIG_KVM_AMD_SEV=y KVM: x86: use u64_to_user_addr() KVM: introduce new vendor op for KVM_GET_DEVICE_ATTR KVM: SEV: publish supported VMSA features KVM: SEV: store VMSA features in kvm_sev_info KVM: x86: add fields to struct kvm_arch for CoCo features KVM: x86: Add supported_vm_types to kvm_caps KVM: SEV: sync FPU and AVX state at LAUNCH_UPDATE_VMSA time KVM: SEV: introduce to_kvm_sev_info KVM: SEV: define VM types for SEV and SEV-ES KVM: SEV: introduce KVM_SEV_INIT2 operation KVM: SEV: allow SEV-ES DebugSwap again selftests: kvm: add tests for KVM_SEV_INIT2 selftests: kvm: switch to using KVM_X86_*_VM Sean Christopherson (1): KVM: SVM: Invert handling of SEV and SEV_ES feature flags Documentation/virt/kvm/api.rst | 2 + .../virt/kvm/x86/amd-memory-encryption.rst | 52 +++++- arch/x86/include/asm/fpu/api.h | 3 + arch/x86/include/asm/kvm-x86-ops.h | 1 + arch/x86/include/asm/kvm_host.h | 8 +- arch/x86/include/uapi/asm/kvm.h | 12 ++ arch/x86/kernel/fpu/xstate.h | 2 - arch/x86/kvm/Makefile | 7 +- arch/x86/kvm/cpuid.c | 2 +- arch/x86/kvm/svm/sev.c | 172 ++++++++++++++---- arch/x86/kvm/svm/svm.c | 27 ++- arch/x86/kvm/svm/svm.h | 43 ++++- arch/x86/kvm/x86.c | 170 +++++++++++------ arch/x86/kvm/x86.h | 2 + tools/testing/selftests/kvm/Makefile | 1 + .../selftests/kvm/include/kvm_util_base.h | 11 +- .../selftests/kvm/include/x86_64/processor.h | 6 - .../selftests/kvm/include/x86_64/sev.h | 16 +- tools/testing/selftests/kvm/lib/kvm_util.c | 1 - .../selftests/kvm/lib/x86_64/processor.c | 14 +- tools/testing/selftests/kvm/lib/x86_64/sev.c | 30 ++- .../selftests/kvm/set_memory_region_test.c | 8 +- .../selftests/kvm/x86_64/sev_init2_tests.c | 149 +++++++++++++++ 23 files changed, 569 insertions(+), 170 deletions(-) create mode 100644 tools/testing/selftests/kvm/x86_64/sev_init2_tests.c