From patchwork Tue Apr 16 20:19:34 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paolo Bonzini X-Patchwork-Id: 13632547 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 63C9E13B588 for ; Tue, 16 Apr 2024 20:19:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713298787; cv=none; b=YSih9zKXKpDNbB9/3g5lN/eDITlDPrlQNUoGug25vVRrdG0INJoG+dF/96zDp3xmrJ9MaJcEG6X9EfSNYRx8dYdpgz3Ux5BABKd/8lvWVTSJFHX/4sOw2lPECcRjTl1RVBTVlNsO525jVWOz7lEqtm6CJvtrglM0po5iedxwz8I= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713298787; c=relaxed/simple; bh=YjX/06cQ6ZQ25fZLpkb7Kj2DDn9st6yNe4LsYowwFIE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=YMALZjKNhZSB0cCWss7D/GG/Hi4sF2ITCkjEs3ukeg3a4I/xZH29l3YBRs99Y04krCpMNSmxq9apRmbugDP90hQz24Q64KZdFf17qOQpwlG1OBt9jukThYLkITxR06x1R/HKlmr1XP7yzadcv5PXf2hiAMBnuLC//ZU+KnOaozA= 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=N2qj5T4e; arc=none smtp.client-ip=170.10.129.124 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="N2qj5T4e" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1713298784; 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: in-reply-to:in-reply-to:references:references; bh=RpANWCnoonzcuXE3SFnF5+HA6HkatDPoVc2CRFiWCW8=; b=N2qj5T4erCnLoU9NvvPCkxyacAogy14zPTLAounS/sa4KhidI5bjefGcZnsJ1bOXJjKC6X KtTEcU1T4rCB00KaQOv64b1Cs7vVTpqvXP10H4iRbf6GKZ49Rdy5QP383JbUyRcdhVVg6j WuvZ5Fha2CKh5VU+SPcx6eWZeohiX/8= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-483-e2XdyAs-Mgapr8S3DEfO-A-1; Tue, 16 Apr 2024 16:19:39 -0400 X-MC-Unique: e2XdyAs-Mgapr8S3DEfO-A-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) (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 B26083C000AE; Tue, 16 Apr 2024 20:19:38 +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 8281018209F; Tue, 16 Apr 2024 20:19:38 +0000 (UTC) From: Paolo Bonzini To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: isaku.yamahata@intel.com, xiaoyao.li@intel.com, binbin.wu@linux.intel.com, chao.gao@intel.com Subject: [PATCH v2 09/10] KVM: x86/mmu: Use PFERR_GUEST_ENC_MASK to indicate fault is private Date: Tue, 16 Apr 2024 16:19:34 -0400 Message-ID: <20240416201935.3525739-10-pbonzini@redhat.com> In-Reply-To: <20240416201935.3525739-1-pbonzini@redhat.com> References: <20240416201935.3525739-1-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 10.11.54.1 SEV-SNP defines PFERR_GUEST_ENC_MASK (bit 34) in page-fault error bits to represent the guest page is encrypted. Use the bit to designate that the page fault is private and that it requires looking up memory attributes. The vendor kvm page fault handler should set PFERR_GUEST_ENC_MASK bit based on their fault information. It may or may not use the hardware value directly or parse the hardware value to set the bit. Based on a patch by Isaku Yamahata. Signed-off-by: Paolo Bonzini --- arch/x86/include/asm/kvm_host.h | 2 ++ arch/x86/kvm/mmu/mmu.c | 9 +++++++++ arch/x86/kvm/mmu/mmu_internal.h | 2 +- 3 files changed, 12 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 9f92bdb78504..7c73952b6f4e 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -264,6 +264,7 @@ enum x86_intercept_stage; #define PFERR_SGX_BIT 15 #define PFERR_GUEST_FINAL_BIT 32 #define PFERR_GUEST_PAGE_BIT 33 +#define PFERR_GUEST_ENC_BIT 34 #define PFERR_IMPLICIT_ACCESS_BIT 48 #define PFERR_PRESENT_MASK BIT(PFERR_PRESENT_BIT) @@ -275,6 +276,7 @@ enum x86_intercept_stage; #define PFERR_SGX_MASK BIT(PFERR_SGX_BIT) #define PFERR_GUEST_FINAL_MASK BIT_ULL(PFERR_GUEST_FINAL_BIT) #define PFERR_GUEST_PAGE_MASK BIT_ULL(PFERR_GUEST_PAGE_BIT) +#define PFERR_GUEST_ENC_MASK BIT_ULL(PFERR_GUEST_ENC_BIT) #define PFERR_IMPLICIT_ACCESS BIT_ULL(PFERR_IMPLICIT_ACCESS_BIT) #define PFERR_NESTED_GUEST_PAGE (PFERR_GUEST_PAGE_MASK | \ diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 00eef18ca1ae..33aea47dce8b 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -5793,6 +5793,7 @@ int noinline kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, u64 err { int r, emulation_type = EMULTYPE_PF; bool direct = vcpu->arch.mmu->root_role.direct; + struct kvm *kvm = vcpu->kvm; /* * IMPLICIT_ACCESS is a KVM-defined flag used to correctly perform SMAP @@ -5808,6 +5809,14 @@ int noinline kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, u64 err if (WARN_ON_ONCE(!VALID_PAGE(vcpu->arch.mmu->root.hpa))) return RET_PF_RETRY; + /* + * There is no vendor code that can set PFERR_GUEST_ENC_MASK for + * software-protected VMs. Compute it here. + */ + if (kvm->arch.vm_type == KVM_X86_SW_PROTECTED_VM && + kvm_mem_is_private(kvm, cr2_or_gpa >> PAGE_SHIFT)) + error_code |= PFERR_GUEST_ENC_MASK; + r = RET_PF_INVALID; if (unlikely(error_code & PFERR_RSVD_MASK)) { r = handle_mmio_page_fault(vcpu, cr2_or_gpa, direct); diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h index 49b428cca04e..7c2ba50cec68 100644 --- a/arch/x86/kvm/mmu/mmu_internal.h +++ b/arch/x86/kvm/mmu/mmu_internal.h @@ -290,6 +290,7 @@ static inline int kvm_mmu_do_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, .present = err & PFERR_PRESENT_MASK, .rsvd = err & PFERR_RSVD_MASK, .user = err & PFERR_USER_MASK, + .is_private = vcpu->kvm->arch.has_private_mem && (err & PFERR_GUEST_ENC_MASK), .prefetch = prefetch, .is_tdp = likely(vcpu->arch.mmu->page_fault == kvm_tdp_page_fault), .nx_huge_page_workaround_enabled = @@ -298,7 +299,6 @@ static inline int kvm_mmu_do_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, .max_level = KVM_MAX_HUGEPAGE_LEVEL, .req_level = PG_LEVEL_4K, .goal_level = PG_LEVEL_4K, - .is_private = kvm_mem_is_private(vcpu->kvm, cr2_or_gpa >> PAGE_SHIFT), }; int r;