From nobody Thu Apr 2 20:25:31 2026 Received: from mail-pl1-f202.google.com (mail-pl1-f202.google.com [209.85.214.202]) (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 D54D23C661A for ; Thu, 26 Mar 2026 17:50:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.202 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774547408; cv=none; b=cFh8Idl1qWPvuVX1+2d+InXyvCGnQwsns/1k/ZZ5NWGRjNp0injWFIMmS1zCYHzGCFF6P3DfSiEC6+t9BWGSaUNiTHxIpOtXbvzJQiI8PGtlktkAkWkVnjU6bOjk+s3KSnsIfyaVPza3XxU9pe5/vpRs12Zdb0ye9uP60vul5no= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774547408; c=relaxed/simple; bh=yXQYjGUPut6PXkdfSl0YRjFdLTlF4PK0M5tnPbSrd0s=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=o7m0Upc196rm3uDPQSeNtRv8rZ/pJLluHEgsGT4YJjJoh/ZjHOOyPJjv/fsXO0RRGiJntuAwZhbj4rXhdGOcatC2/S0OZklhrpnpkcq9E/VM7ypnKwiepMwbPdd0lAdqhX/3oPZiJni3XxkFpzGWqXD5/zT0GetaKJMCTLN1F1g= 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=ZY2Ci+rt; arc=none smtp.client-ip=209.85.214.202 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="ZY2Ci+rt" Received: by mail-pl1-f202.google.com with SMTP id d9443c01a7336-2b0c92ff4ebso4385255ad.2 for ; Thu, 26 Mar 2026 10:50:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1774547406; x=1775152206; 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=A0q74nR0onjV0BK2f2Df6n+ntIHSSjqGFZqE9Y1ouTk=; b=ZY2Ci+rtjocYXKdoxe2xkSmkz5kEfJqCeT1H6LOHL1yxOjs1T8n8TV5VwH/c83JnzQ dkJ5ooEHVrsGIJkI+1n9cMDeVp+H6yglucu+lr4akKukEdYJpiEXx+/2jfR7GMJritu4 bU7+7v74FIYJ8dDMOE0aG/d8gXOVOOgMncafVWlgQSldedJAdTyKLGfgUWe/kVbJxlpK buOMAlX7hRZm6TZ0rxDFZUXWyzxXVQBpg00iDl2KOTTzHSf9N81jWwzA6r2F3/MmWpGG wYZ+W+olvRHL7m112O1cjtKK5vTBAajZDog14jcry0C22LiGvHR2nRc/Yfd5Pa6cCq3J /I3Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1774547406; x=1775152206; 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=A0q74nR0onjV0BK2f2Df6n+ntIHSSjqGFZqE9Y1ouTk=; b=TmAku9b+vk6Lz2vKd0CEuYtcKWbjEqtHQzktCE/s/Jg5Zs4zkNpGxUkH4Cq+JszN8R inVxakhbdbpEdNCWSyT8ksFIC6U71S1toS/9vEF4tMK6u7q/x7FP4hQnmuh5fRs9sHQp 0EjcPNU+68vbn4lQLuKhZitORkS2D+uAvnuMomltJgsB0MuQ8KN7AeSFVpnBfsAhrR1M ovHQY3GWZmrbY1uQsBoSxgjgLUvwdq1NeIQ6P35tX5zkQnqiPBscZU/eNZlQfWjO7d6U w7TAC9cGfYkw87Ltbyan1oRQzMLrl737P09J+0cswOZfliArCfee+lbKVzOyfRoKQWwQ kkMA== X-Forwarded-Encrypted: i=1; AJvYcCXmAt8FYNK39C1Xq+cpRaPG33c0ys0/hXvMbnF+T6LV8SUETchKz77x6DagtsatSQEepX3QjjYe6QidYXI=@vger.kernel.org X-Gm-Message-State: AOJu0Ywz5VDGJ/eSqDxa5CuTHeePChkwhzXJXF1UGhLgqztgJ2eDtyZY vFHKKcwHdexLZV/Vuw5NMjl19Fjraon9aguNZFhujEGAgjT9f2PP5NdPZeRmhjCfxHfDEjQFGT6 W9JdOihQnHV8P9Q== X-Received: from plbku14.prod.google.com ([2002:a17:903:288e:b0:2b0:ae36:890]) (user=jmattson job=prod-delivery.src-stubby-dispatcher) by 2002:a17:903:1b45:b0:2b0:5fa5:a68c with SMTP id d9443c01a7336-2b0b09a0aafmr93375115ad.9.1774547406079; Thu, 26 Mar 2026 10:50:06 -0700 (PDT) Date: Thu, 26 Mar 2026 10:49:22 -0700 In-Reply-To: <20260326174944.3820245-1-jmattson@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260326174944.3820245-1-jmattson@google.com> X-Mailer: git-send-email 2.53.0.1018.g2bb0e51243-goog Message-ID: <20260326174944.3820245-5-jmattson@google.com> Subject: [PATCH v6 04/10] KVM: x86: nSVM: Set vmcb02.g_pat correctly for nested NPT From: Jim Mattson To: Paolo Bonzini , Jonathan Corbet , Shuah Khan , Sean Christopherson , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , kvm@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, Yosry Ahmed Cc: Jim Mattson Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" When KVM_X86_QUIRK_NESTED_SVM_SHARED_PAT is disabled and nested NPT is enabled in vmcb12, copy the (cached and validated) vmcb12 g_pat field to vmcb02's g_pat, giving L2 its own independent guest PAT register. When the quirk is enabled (default), or 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 --- 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 0ad1e0348492..405209f8c4cd 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -721,9 +721,6 @@ 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; @@ -754,6 +751,13 @@ static void nested_vmcb02_prepare_save(struct vcpu_svm= *svm) vmcb_mark_dirty(vmcb02, VMCB_CET); } =20 + if (l2_has_separate_pat(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 2.53.0.1018.g2bb0e51243-goog