From nobody Tue Dec 16 14:43:48 2025 Received: from mail-pj1-f74.google.com (mail-pj1-f74.google.com [209.85.216.74]) (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 18A3F381E72 for ; Thu, 30 Oct 2025 20:10:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.74 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761855030; cv=none; b=WX6kjKpLtafl6tvCnJLbl5ENhkL7WFCQwoV4eJGVTrFNWRd1UdJ4++rmOBZu0VrkoVvSCLNUzO61helXLdncXcC4UQdg56fy6p/LjDyRqbf7QwonOijkjo669EWc1sMsZmNvTs3jcQbuqP4F4IWQ4gjLdRwqAFgKsSn/7uLyKjM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761855030; c=relaxed/simple; bh=ko0pi49hMMjXayjy5Hc2PgynQuEfPA92uCBi4fQ9ie0=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=D+sEt2wIEO3UUy2NnnKFn0zAQZQNykTkGSm6eOnETgibhIT9Qp6K5P1eZDhW1iGswJJt3Hd6E155332agPHaxs2cbAt13+nbsz9NTM5wQVrCN2DyLlGpSL2JtaOC0eb9T5+YwzE8C0dWqAfNLmhMWtIJkMZAMQ6CMNO5TjnC9bU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=nj+B+efx; arc=none smtp.client-ip=209.85.216.74 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--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="nj+B+efx" Received: by mail-pj1-f74.google.com with SMTP id 98e67ed59e1d1-34077439124so1055055a91.1 for ; Thu, 30 Oct 2025 13:10:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1761855028; x=1762459828; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:from:to:cc:subject:date:message-id:reply-to; bh=KH8ZMUFkaBzXjpSahKr3XCuyUdT65ecO9/HP1PAb4RI=; b=nj+B+efxjj+BjjpLsFBs9asAhG14bnqqJoNM5z9YofCOlxRMnFSVu3n/sY1Mt5fItP CsTO3RH93jnXS0R4+5Up/MU3OJ/hE5yc16bnWjmMoyvqDtelHrG7uinV/OtYrmiPpRqW G+/oE3ScYnxzem5B51i7E1lFke8cAGzXx+nkk+JrPfrhbAprJ/bYXlXcXZipbOUJizka YmtGSBTUVHJSgDMV10WoXwjgCiEGO5D6mOvCAkaoazLbR7hL7nvLax64VctyUovZeoky +ZgWn9RP+wSxUsFxnUlO6/qj936N3zt8ywlIltb8m7DHrZ5LUALFvXureoaiY9xAkpAU CAAA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1761855028; x=1762459828; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=KH8ZMUFkaBzXjpSahKr3XCuyUdT65ecO9/HP1PAb4RI=; b=WFeGcnR2mKNP61h2nmR7PUq1tsO9dpGh3VUJCG+GoNZsN1I7mhteeQVrF67sCp0QYm KxgLmrLoLMiNWRGcQhopOUjdDAT2tbchUWeav0N8vfWrx6p5hkS9afZ2qlE0HiLdrPOS 3mgN1fWPXkP+BSmTvRuTuxFmrcveGF10Ki54nwrArf/fqZXb0LLmqwpy70MATmPV6K7y f/nEKI+tE6oisC0t9QcUeHufqcl+teBt124RfE6/m3U9sn1iL0BoCZkcxL7yLBiwAxjc z5murBQ8YaoiNPJws2TNiK0aJCKJ5RXWDDaTucUC6SdEbWPU2GOE9zyl9aNHcOP069x1 9I8Q== X-Forwarded-Encrypted: i=1; AJvYcCVyAByL8BY85nmZrpGAn0bABjLW+2t6VzL2zTeLXTi+NAc5W1sckGIc5vlTs7lP9mqhUBji3R69mhSR/Ww=@vger.kernel.org X-Gm-Message-State: AOJu0YzP5fQVLY1J2zGVtwM5o0+URUX9Xl61CPm+AFQHU/FjgRT4ghXL Bna59f/xhl86+ufFXvZeujVJeX2Xm8E8D5sFSvEDWzu4soUUfvBKZHKYytpv381//JrWNdGqK3y 19yAROA== X-Google-Smtp-Source: AGHT+IGrJrKalEV3VAWt2uGzDiDeYhZVGRjeI1LK3deyE8hSeRDQF6nrnXg4JLxn0CpF+AukaegC2zqX/UE= X-Received: from pjbgj23.prod.google.com ([2002:a17:90b:1097:b0:33b:cfaf:ce3e]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:1801:b0:330:6d5e:f17b with SMTP id 98e67ed59e1d1-34083074dddmr1219299a91.21.1761855028166; Thu, 30 Oct 2025 13:10:28 -0700 (PDT) Reply-To: Sean Christopherson Date: Thu, 30 Oct 2025 13:09:35 -0700 In-Reply-To: <20251030200951.3402865-1-seanjc@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20251030200951.3402865-1-seanjc@google.com> X-Mailer: git-send-email 2.51.1.930.gacf6e81ea2-goog Message-ID: <20251030200951.3402865-13-seanjc@google.com> Subject: [PATCH v4 12/28] KVM: TDX: WARN if mirror SPTE doesn't have full RWX when creating S-EPT mapping From: Sean Christopherson To: Marc Zyngier , Oliver Upton , Tianrui Zhao , Bibo Mao , Huacai Chen , Madhavan Srinivasan , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Christian Borntraeger , Janosch Frank , Claudio Imbrenda , Sean Christopherson , Paolo Bonzini , "Kirill A. Shutemov" Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, kvm@vger.kernel.org, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, x86@kernel.org, linux-coco@lists.linux.dev, linux-kernel@vger.kernel.org, Ira Weiny , Kai Huang , Binbin Wu , Michael Roth , Yan Zhao , Vishal Annapurve , Rick Edgecombe , Ackerley Tng Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Pass in the mirror_spte to kvm_x86_ops.set_external_spte() to provide symmetry with .remove_external_spte(), and assert in TDX that the mirror SPTE is shadow-present with full RWX permissions (the TDX-Module doesn't allow the hypervisor to control protections). Signed-off-by: Sean Christopherson Reviewed-by: Binbin Wu Reviewed-by: Kai Huang --- arch/x86/include/asm/kvm_host.h | 2 +- arch/x86/kvm/mmu/tdp_mmu.c | 3 +-- arch/x86/kvm/vmx/tdx.c | 6 +++++- 3 files changed, 7 insertions(+), 4 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_hos= t.h index b5867f8fe6ce..87a5f5100b1d 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1848,7 +1848,7 @@ struct kvm_x86_ops { void *external_spt); /* Update the external page table from spte getting set. */ int (*set_external_spte)(struct kvm *kvm, gfn_t gfn, enum pg_level level, - kvm_pfn_t pfn_for_gfn); + u64 mirror_spte); =20 /* Update external page tables for page table about to be freed. */ int (*free_external_spt)(struct kvm *kvm, gfn_t gfn, enum pg_level level, diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c index e1a96e9ea1bb..9c26038f6b77 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.c +++ b/arch/x86/kvm/mmu/tdp_mmu.c @@ -515,7 +515,6 @@ static int __must_check set_external_spte_present(struc= t kvm *kvm, tdp_ptep_t sp bool was_present =3D is_shadow_present_pte(old_spte); bool is_present =3D is_shadow_present_pte(new_spte); bool is_leaf =3D is_present && is_last_spte(new_spte, level); - kvm_pfn_t new_pfn =3D spte_to_pfn(new_spte); int ret =3D 0; =20 KVM_BUG_ON(was_present, kvm); @@ -534,7 +533,7 @@ static int __must_check set_external_spte_present(struc= t kvm *kvm, tdp_ptep_t sp * external page table, or leaf. */ if (is_leaf) { - ret =3D kvm_x86_call(set_external_spte)(kvm, gfn, level, new_pfn); + ret =3D kvm_x86_call(set_external_spte)(kvm, gfn, level, new_spte); } else { void *external_spt =3D get_external_spt(gfn, new_spte, level); =20 diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c index 7ab67ad83677..658e0407eb21 100644 --- a/arch/x86/kvm/vmx/tdx.c +++ b/arch/x86/kvm/vmx/tdx.c @@ -1629,14 +1629,18 @@ static int tdx_mem_page_record_premap_cnt(struct kv= m *kvm, gfn_t gfn, } =20 static int tdx_sept_set_private_spte(struct kvm *kvm, gfn_t gfn, - enum pg_level level, kvm_pfn_t pfn) + enum pg_level level, u64 mirror_spte) { struct kvm_tdx *kvm_tdx =3D to_kvm_tdx(kvm); + kvm_pfn_t pfn =3D spte_to_pfn(mirror_spte); =20 /* TODO: handle large pages. */ if (KVM_BUG_ON(level !=3D PG_LEVEL_4K, kvm)) return -EIO; =20 + WARN_ON_ONCE(!is_shadow_present_pte(mirror_spte) || + (mirror_spte & VMX_EPT_RWX_MASK) !=3D VMX_EPT_RWX_MASK); + /* * Read 'pre_fault_allowed' before 'kvm_tdx->state'; see matching * barrier in tdx_td_finalize(). --=20 2.51.1.930.gacf6e81ea2-goog