From nobody Thu Apr 2 01:53:34 2026 Received: from mail-pl1-f201.google.com (mail-pl1-f201.google.com [209.85.214.201]) (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 D1C2239E19F for ; Fri, 27 Mar 2026 23:40:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774654836; cv=none; b=S4bk/OSryzAHxpW7PZQ0L7gpP+x8r6udVJIvK1Y/KlbdHDhUpIJnvuPV8+GfNXKr2jW6nckmoal+FXS0CZh/IJDSkAayKE33zIumpeI1OcmxnsQizJFg9nnl6DJ03AMNch3+P3TTckJh4+xFhNjwyFQ+/fwH7xnwJXVBHVVQzn0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774654836; c=relaxed/simple; bh=zQH8QY/cLFF1GBuomhulf/vBI5L31KzAMmoyN+E+i6E=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=rZ7vQ52kEH0OrvrWMe2wqLf1/SXzgrf5dnvLsdm1qg1K5R/cGI07hzisLLfk0Gg3PCmYRe6mNr0+b0IN2U5K5lU4skVUlcXi22mERbgLHdRJO9FaIWEGBmLaINSwbwcGSSlfGQCeI7v9jK8FvVlbeCP8hsEco6FIJJW0NYYvLHk= 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=dbI+gFCl; arc=none smtp.client-ip=209.85.214.201 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="dbI+gFCl" Received: by mail-pl1-f201.google.com with SMTP id d9443c01a7336-2b0be75dfd4so35682365ad.1 for ; Fri, 27 Mar 2026 16:40:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1774654832; x=1775259632; 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=bFrhht4F+Ql8p4REBNfHrn2pw253p4SlLxIhEftRqHY=; b=dbI+gFClmLUYBnwWBGa+Y5RX8u1dUTRxd3JsLFwDNKXK691O6YTDo7vxzCFoDDum3m CcISLCmAyJxD8xugTxFzE1UKrsGcgjG9l9mWLCjpEJDa74O1zG59QYQK7Si9eBnQHoup 7FoIhtj/QHWfBdyPDmGS1QYIGikJL5o1MmCrg8JBftsO8EgaKgsJL2XAfWJ2133kZ85P u/m/WNh8AbRfHz719XLd8/0bUdOQYimVwfS886kNVjuh/GYVMiCiMWa7aloGNBVPxtkW S1GeU/gufuzXONmoTwfIdwd1IDQZfbnNZJvOoPOey0cKvHOkp1wyV/YCbxJ5KD6ttqMJ AJ4g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1774654832; x=1775259632; 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=bFrhht4F+Ql8p4REBNfHrn2pw253p4SlLxIhEftRqHY=; b=biT3MG7MbN2jSaHehdV+afDCRmdHzVFslU2YGLWDzT8lwlLcgEUi7yBFJmtn1RQllv 3bhr7GAls+UVyrHOhu+tGnYsgbyiCtGcjtObC4ocn+DAFmr7L7TbU+SUMz+mzKxOQiX8 XIpm7LWD2D8Z1GE823CqetEqyvLp9937FegHqBSCn03eg7EVaX4DxZ2qVWv/Rj7VNOHw Cr79X3ADUp7nomKxuo8nByZGNAXkQiIZKi3kpeEPnzdZJX9Llugr0J+DZWScQfri9Q4u ZGcrPIhYWDm2eNgK8dOVHkYqx+372rMWAZsNXcc8aH4aN1dao052Cq9SWFWnLv0Lt1tw mIpg== X-Forwarded-Encrypted: i=1; AJvYcCU4hvua6cxtf7C9dVbuIf8XTcNwXWNgE+xizEDMeQG5dkuC1hFozdKaL16PniHodH804SY8zk1hPJmbzzk=@vger.kernel.org X-Gm-Message-State: AOJu0YyMP3+ojw9zIEVQ8OWKHu9rB0N+wX2npOkQyPjjTB4LD6r51/us /KFea5bErRRTLnjfYoVUv3ptw7KWnUibbyv/Ktv0SodoKNV5JwXJ/CgammhSwcen18OZB/xtNbI D6gR1TmF/SofIEQ== X-Received: from plbkg5.prod.google.com ([2002:a17:903:605:b0:2ae:3bca:37a5]) (user=jmattson job=prod-delivery.src-stubby-dispatcher) by 2002:a17:902:e5cc:b0:2b0:b290:f2f4 with SMTP id d9443c01a7336-2b0cdd40053mr48908955ad.32.1774654831920; Fri, 27 Mar 2026 16:40:31 -0700 (PDT) Date: Fri, 27 Mar 2026 16:40:09 -0700 In-Reply-To: <20260327234023.2659476-1-jmattson@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260327234023.2659476-1-jmattson@google.com> X-Mailer: git-send-email 2.53.0.1018.g2bb0e51243-goog Message-ID: <20260327234023.2659476-3-jmattson@google.com> Subject: [PATCH v7 2/9] KVM: x86: nSVM: Clear VMCB_NPT clean bit when updating hPAT from guest mode 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 running an L2 guest and writing to MSR_IA32_CR_PAT, the host PAT value is stored in both vmcb01's g_pat field and vmcb02's g_pat field, but the clean bit was only being cleared for vmcb02. Introduce the helper vmcb_set_gpat() which sets vmcb->save.g_pat and marks the VMCB dirty for VMCB_NPT. Use this helper in both svm_set_msr() for updating vmcb01 and in nested_vmcb02_compute_g_pat() for updating vmcb02, ensuring both VMCBs' NPT fields are properly marked dirty. Fixes: 4995a3685f1b ("KVM: SVM: Use a separate vmcb for the nested L2 guest= ") Signed-off-by: Jim Mattson --- arch/x86/kvm/svm/nested.c | 2 +- arch/x86/kvm/svm/svm.c | 3 +-- arch/x86/kvm/svm/svm.h | 6 ++++++ 3 files changed, 8 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index 5ff01d2ac85e..32fa8e688c00 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -697,7 +697,7 @@ void nested_vmcb02_compute_g_pat(struct vcpu_svm *svm) return; =20 /* FIXME: merge g_pat from vmcb01 and vmcb12. */ - svm->nested.vmcb02.ptr->save.g_pat =3D svm->vmcb01.ptr->save.g_pat; + vmcb_set_gpat(svm->nested.vmcb02.ptr, svm->vmcb01.ptr->save.g_pat); } =20 static bool nested_vmcb12_has_lbrv(struct kvm_vcpu *vcpu) diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index d2ca226871c2..af808e83173e 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -2979,10 +2979,9 @@ static int svm_set_msr(struct kvm_vcpu *vcpu, struct= msr_data *msr) if (ret) break; =20 - svm->vmcb01.ptr->save.g_pat =3D data; + vmcb_set_gpat(svm->vmcb01.ptr, data); if (is_guest_mode(vcpu)) nested_vmcb02_compute_g_pat(svm); - vmcb_mark_dirty(svm->vmcb, VMCB_NPT); break; case MSR_IA32_SPEC_CTRL: if (!msr->host_initiated && diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h index 74014110b550..a1d62c3cc3d6 100644 --- a/arch/x86/kvm/svm/svm.h +++ b/arch/x86/kvm/svm/svm.h @@ -439,6 +439,12 @@ static inline bool vmcb12_is_dirty(struct vmcb_ctrl_ar= ea_cached *control, int bi return !test_bit(bit, (unsigned long *)&control->clean); } =20 +static inline void vmcb_set_gpat(struct vmcb *vmcb, u64 data) +{ + vmcb->save.g_pat =3D data; + vmcb_mark_dirty(vmcb, VMCB_NPT); +} + static __always_inline struct vcpu_svm *to_svm(struct kvm_vcpu *vcpu) { return container_of(vcpu, struct vcpu_svm, vcpu); --=20 2.53.0.1018.g2bb0e51243-goog