From nobody Mon Sep 15 11:31:31 2025 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A2F27C71145 for ; Thu, 12 Jan 2023 16:44:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241312AbjALQoq (ORCPT ); Thu, 12 Jan 2023 11:44:46 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42036 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239998AbjALQht (ORCPT ); Thu, 12 Jan 2023 11:37:49 -0500 Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2483118396; Thu, 12 Jan 2023 08:33:59 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1673541239; x=1705077239; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=wlUqvjl7lmCsRVxjYwDxCeLaDvBxV/8y59RWEJKUld8=; b=TwhnAo3x0t/zjy4UAtW8Q6UY0OCAZti+u0shPwl1rEWdnsMTbszGOul2 mdAQR30NIhjxvKMTdQi7mYwd1LSC8H1qOTGZiDgw11i6JN8aMwF2830A1 s8Ukj3pLEofIaRvtguoMJ6Hsh1r//INwj3GlIrjEjHy7Lgjape00RP/Qv z6bkD8JzNOSRMrRHlcB8gXNVksghzsoh5CvKadwl+taLaCuDQrwd+GCJA JmIDfIpYCzWjkx6ZgEwYtny1myhiVVnmmHyVL84cSpqfalL4WovEc35LS vO4cPKiKlqHYvdRyJRzTY+WTdK1T51WFqNFDBdcAXuoSXjoMpUC5xIKst g==; X-IronPort-AV: E=McAfee;i="6500,9779,10588"; a="323811784" X-IronPort-AV: E=Sophos;i="5.97,211,1669104000"; d="scan'208";a="323811784" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Jan 2023 08:33:24 -0800 X-IronPort-AV: E=McAfee;i="6500,9779,10588"; a="721151719" X-IronPort-AV: E=Sophos;i="5.97,211,1669104000"; d="scan'208";a="721151719" Received: from ls.sc.intel.com (HELO localhost) ([143.183.96.54]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Jan 2023 08:33:24 -0800 From: isaku.yamahata@intel.com To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: isaku.yamahata@intel.com, isaku.yamahata@gmail.com, Paolo Bonzini , erdemaktas@google.com, Sean Christopherson , Sagi Shahar , David Matlack , Rick Edgecombe Subject: [PATCH v11 028/113] KVM: x86/mmu: Add address conversion functions for TDX shared bit of GPA Date: Thu, 12 Jan 2023 08:31:36 -0800 Message-Id: <54be4e46ff972359b87fa3fc4952ac2f32415f8f.1673539699.git.isaku.yamahata@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Isaku Yamahata TDX repurposes one GPA bit (51 bit or 47 bit based on configuration) to indicate the GPA is private(if cleared) or shared (if set) with VMM. If GPA.shared is set, GPA is covered by the existing conventional EPT pointed by EPTP. If GPA.shared bit is cleared, GPA is covered by TDX module. VMM has to issue SEAMCALLs to operate. Add a member to remember GPA shared bit for each guest TDs, add address conversion functions between private GPA and shared GPA and test if GPA is private. Because struct kvm_arch (or struct kvm which includes struct kvm_arch. See kvm_arch_alloc_vm() that passes __GPF_ZERO) is zero-cleared when allocated, the new member to remember GPA shared bit is guaranteed to be zero with this patch unless it's initialized explicitly. Co-developed-by: Rick Edgecombe Signed-off-by: Rick Edgecombe Signed-off-by: Isaku Yamahata --- arch/x86/include/asm/kvm_host.h | 4 ++++ arch/x86/kvm/mmu.h | 32 ++++++++++++++++++++++++++++++++ arch/x86/kvm/vmx/tdx.c | 5 +++++ 3 files changed, 41 insertions(+) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_hos= t.h index 35773f925cc5..73c987b3d2b6 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1439,6 +1439,10 @@ struct kvm_arch { */ #define SPLIT_DESC_CACHE_MIN_NR_OBJECTS (SPTE_ENT_PER_PAGE + 1) struct kvm_mmu_memory_cache split_desc_cache; + +#ifdef CONFIG_KVM_MMU_PRIVATE + gfn_t gfn_shared_mask; +#endif }; =20 struct kvm_vm_stat { diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h index 6bdaacb6faa0..a45f7a96b821 100644 --- a/arch/x86/kvm/mmu.h +++ b/arch/x86/kvm/mmu.h @@ -278,4 +278,36 @@ static inline gpa_t kvm_translate_gpa(struct kvm_vcpu = *vcpu, return gpa; return translate_nested_gpa(vcpu, gpa, access, exception); } + +static inline gfn_t kvm_gfn_shared_mask(const struct kvm *kvm) +{ +#ifdef CONFIG_KVM_MMU_PRIVATE + return kvm->arch.gfn_shared_mask; +#else + return 0; +#endif +} + +static inline gfn_t kvm_gfn_shared(const struct kvm *kvm, gfn_t gfn) +{ + return gfn | kvm_gfn_shared_mask(kvm); +} + +static inline gfn_t kvm_gfn_private(const struct kvm *kvm, gfn_t gfn) +{ + return gfn & ~kvm_gfn_shared_mask(kvm); +} + +static inline gpa_t kvm_gpa_private(const struct kvm *kvm, gpa_t gpa) +{ + return gpa & ~gfn_to_gpa(kvm_gfn_shared_mask(kvm)); +} + +static inline bool kvm_is_private_gpa(const struct kvm *kvm, gpa_t gpa) +{ + gfn_t mask =3D kvm_gfn_shared_mask(kvm); + + return mask && !(gpa_to_gfn(gpa) & mask); +} + #endif diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c index e2f5a07ad4e5..a7d42c05a758 100644 --- a/arch/x86/kvm/vmx/tdx.c +++ b/arch/x86/kvm/vmx/tdx.c @@ -781,6 +781,11 @@ static int tdx_td_init(struct kvm *kvm, struct kvm_tdx= _cmd *cmd) kvm_tdx->attributes =3D td_params->attributes; kvm_tdx->xfam =3D td_params->xfam; =20 + if (td_params->exec_controls & TDX_EXEC_CONTROL_MAX_GPAW) + kvm->arch.gfn_shared_mask =3D gpa_to_gfn(BIT_ULL(51)); + else + kvm->arch.gfn_shared_mask =3D gpa_to_gfn(BIT_ULL(47)); + out: /* kfree() accepts NULL. */ kfree(init_vm); --=20 2.25.1