From nobody Sun Apr 5 21:16:08 2026 Received: from mail-pf1-f201.google.com (mail-pf1-f201.google.com [209.85.210.201]) (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 E7C8923ABB9 for ; Tue, 24 Feb 2026 00:55:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771894521; cv=none; b=Xgx0HCn5RlLzPmXfarWcPmBPc4S7ElHRr535NW/R4fAAy1I9+I2cnPu1X9wXmi4g3GL2cJ9ZIOVENo2FlYz8zojrrHns3m3co08AoaukA6bVfi+lVsVWRzO1zCyi6nBVmvmHsdrEbKGBsTmSQfvq1sMcE25pUemBPogm4OCSDGA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771894521; c=relaxed/simple; bh=wugGug88ulZBP+j2+aUrsuqT4ajAwhd5CJ12zCO2pgU=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=YAIS4Ou9TAZdYnG8bG7h3OsxnnnUTp4+yvIzoyLrTAsyl9f9c8am0Ans9Kos00sHUoqSeMZ8XRXI/Y348zWo0oLCh7gKgn3koJwzGdgQYucRkLbxGG2/C+yeCxM1L28uzIeD8JY1VF4fRjVOrnoM1PP/yzKYotaiVJ27zevNXpQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--jmattson.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=IGsOfS0i; arc=none smtp.client-ip=209.85.210.201 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--jmattson.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="IGsOfS0i" Received: by mail-pf1-f201.google.com with SMTP id d2e1a72fcca58-824bbce0a44so22269031b3a.2 for ; Mon, 23 Feb 2026 16:55:14 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1771894514; x=1772499314; 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=5+Hqic4J3q/Gjct4qXtXk7Fpq6XEgqzORDUOT17QFCo=; b=IGsOfS0iiseZTXkRyjMPuRz0yd0R4HwqPg8peUzvpNWGM4sfmbJFQirrEyxDl+yclJ KqZyABpMBorhvUOOYaEAXyS9UHyHDnEZQ3aKjXkgvD6wNClIVL+qxRvPQrDHL0eqLFLr qbP6GAfvs6yboAPk3Of4P+MJhx1ZarlBgNHV/AsvIwjLialHrN+v7bAejZmV63agcpvy R7T/GMM6eQ3ZtAhB2b/tvRz6oPOijmE4bmw3vNuctWp4eBsz3MLwbrnNm8wn6ILxL4MZ 4EqRKEQDaf11prOWe1ERcz0mniE0Y+N+15cJy3ejD7Z2Vpx7aDh+yGeGsJaZ/Bar95I1 P1iw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1771894514; x=1772499314; 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=5+Hqic4J3q/Gjct4qXtXk7Fpq6XEgqzORDUOT17QFCo=; b=DJy1h9VMJ7LG5gWhkwlpq5TGmbhJ3d/LzSm+rOMVt185bYVoSqnko6iKyzA2d2Ajmc 3uvcmoWL4MzdkYuMzAXyLY6rVqczTlPXJBk5/3Kh/k7hLhtHwsAD2dltftn1g5+vrQe8 VOe1CuCFaFLToIeJ/8zzIYrWK6Km5onuU1xb4+lFVw16OwutfscHcAe0sdc91Dlg8g3W RJjvjousWjBUxnrpGYeAzmALV17Ih0zkLHpeQl9ilE4Vgy01Byx6IJ+RRc1gZTuTr3yt ogzr3RcZRMmh0l74Nqr2OttTk/dI6SekhR1rDomUz11JvOm7sLWwCpYVz5YCPL9hChud E33g== X-Forwarded-Encrypted: i=1; AJvYcCVQbxpoqx+3feYTGDuQ7EU4y9RGnxMwpQ3hWMP/02Y6+cQADGvfcWrsB2YDMk7V5ax8f97134hQR4Q5ek4=@vger.kernel.org X-Gm-Message-State: AOJu0YzdesRtnlkpxxUt921PUfo4CC2MnuL7yviDQ1mHYtd7sNmi9bZP r5lR9QvBr+PY06kWpxZhJSdwyUI3p9zLf5saBXbH8fWAhhtfk7dUcVS5uIiSs8JgWPCMB/iniTo TOfQD4qc5L7ktcQ== X-Received: from pfbfb35.prod.google.com ([2002:a05:6a00:2da3:b0:824:ba70:4416]) (user=jmattson job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a00:92a5:b0:81f:46ce:e90 with SMTP id d2e1a72fcca58-826da910433mr9511795b3a.28.1771894514274; Mon, 23 Feb 2026 16:55:14 -0800 (PST) Date: Mon, 23 Feb 2026 16:54:42 -0800 In-Reply-To: <20260224005500.1471972-1-jmattson@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260224005500.1471972-1-jmattson@google.com> X-Mailer: git-send-email 2.53.0.371.g1d285c8824-goog Message-ID: <20260224005500.1471972-5-jmattson@google.com> Subject: [PATCH v5 04/10] KVM: x86: nSVM: Set vmcb02.g_pat correctly for nested NPT From: Jim Mattson To: Sean Christopherson , Paolo Bonzini , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Shuah Khan , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, Yosry Ahmed Cc: Jim Mattson , Yosry Ahmed Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" When nested NPT is enabled in vmcb12, copy the (cached and validated) vmcb12 g_pat field to the guest PAT register. Under KVM, the guest PAT register lives in svm->nested.save.g_pat. When NPT is enabled, but nested NPT is disabled, copy L1's IA32_PAT MSR to the vmcb02 g_pat field, since L2 shares the IA32_PAT MSR with L1. When NPT is disabled, the g_pat field is ignored by hardware. Fixes: 15038e147247 ("KVM: SVM: obey guest PAT") Signed-off-by: Jim Mattson Reviewed-by: Yosry Ahmed --- arch/x86/kvm/svm/nested.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index 91b35adb83f8..dc8275837120 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -724,9 +724,6 @@ static void nested_vmcb02_prepare_save(struct vcpu_svm = *svm) struct vmcb *vmcb02 =3D svm->nested.vmcb02.ptr; struct kvm_vcpu *vcpu =3D &svm->vcpu; =20 - nested_vmcb02_compute_g_pat(svm); - vmcb_mark_dirty(vmcb02, VMCB_NPT); - /* Load the nested guest state */ if (svm->nested.vmcb12_gpa !=3D svm->nested.last_vmcb12_gpa) { new_vmcb12 =3D true; @@ -757,6 +754,13 @@ static void nested_vmcb02_prepare_save(struct vcpu_svm= *svm) vmcb_mark_dirty(vmcb02, VMCB_CET); } =20 + if (nested_npt_enabled(svm)) { + if (unlikely(new_vmcb12 || vmcb12_is_dirty(control, VMCB_NPT))) + vmcb_set_gpat(vmcb02, svm->nested.save.g_pat); + } else if (npt_enabled) { + vmcb_set_gpat(vmcb02, vcpu->arch.pat); + } + kvm_set_rflags(vcpu, save->rflags | X86_EFLAGS_FIXED); =20 svm_set_efer(vcpu, svm->nested.save.efer); --=20 2.53.0.371.g1d285c8824-goog