From nobody Thu Apr 2 20:26:40 2026 Received: from mail-pg1-f201.google.com (mail-pg1-f201.google.com [209.85.215.201]) (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 BF7E6318BBB for ; Thu, 12 Feb 2026 15:59:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770911957; cv=none; b=gMyUZNXOJqBM7eij0ckx5//2FztNhFi6IDS91LLV0IDJywZQHWA+UZrocn/c8I3xuDxVpUpIVjKa65FC/0zcWF0YFG4LO3djbFif6vo3Zo4L9lAussHTWFbVEP73klfVr5pXtB3gF93XDlk48Avm8JoxdIeNSt5IHzjI0rvko0E= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770911957; c=relaxed/simple; bh=mbEr3hzyszjJo46OU/qkjXN9L7/rAyLb4rEYR0jpuE8=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=PDe3ZOZ3qavP3orsUcI9tsg2wMfHscHcuwWwqfHb5yutJlgrL7wkMfIlr4few7Bhmfku00kcuosl5e1NmMe1N4kHrneBCDxfMPNv3TBuchkPE7DBxrW/wkIBiauBqi19becXh7DT8NUGsYOmWlxoCAEgiBm0KLz7OusjnlbQ1BE= 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=gaLaqEal; arc=none smtp.client-ip=209.85.215.201 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="gaLaqEal" Received: by mail-pg1-f201.google.com with SMTP id 41be03b00d2f7-c6e18f1cb86so3864136a12.0 for ; Thu, 12 Feb 2026 07:59:14 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1770911954; x=1771516754; 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=J6K8kyx9CcUqpPEEuGOr7xIDm2PG4sM2n5DYfDKzhGk=; b=gaLaqEalXK25FPBVCJfjG1nVXZh0QROSDjhxJ/M22T8D4S9eQw2gyRcnv5dWJ7Z7KD ez/cl60A9fXcypTgecR2Znf+guBnb+Ar+l+rboZ8GYn+mmL6wpRHRyM7/osi4Y4yOblF 4QbVbbYW0VEIGs+hhV1rQXPjPD+8B+90FFAE8Zl+CTt7Xnurcq451tFoonrLXxW9nYf9 RKfNbedQMa9bgq7LSqko/v2wys0MyQylnP1wYYVp+AI19FSJYgBa13gpJr8PxjQ0/ZCj vqeHO784iZ0b+mVWbJ0Yu7hKmvMpGiJko2jPG8X4J8R/Tkd+8xcG8jocyyRL/Lq+DFIs ENKQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1770911954; x=1771516754; 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=J6K8kyx9CcUqpPEEuGOr7xIDm2PG4sM2n5DYfDKzhGk=; b=ZO4g+1bt0CZnYxhO3sIgBFUNC++MgZXTL4gh3JEeEMHtjymtQCnhrbQRAjjPF7A1U0 y4i8f1YY7GhoV5fgIf5O6M7oclzCRqltJ8X6mKoj9jXiAuotSr4on4+b0DwwfC4cFJj8 DlY+nvicEnMErG/ID+6znQUrmZZ1U0BjEOkNCwjeWlt27ehsaHIXej7m632ieUImhIrK C1FxxuRBHaUs3qbzwfNZxoyYAycRAaVZlz08X1yftpZoy1TBwErdNE5zpfsWh8h6N2vF hWM8dW+jUKImwWcR+en+0mH44/wQ4soqFG1GZvCJVf8L0xNT+l7EJqpO97N5jpnrUB3u bbZQ== X-Forwarded-Encrypted: i=1; AJvYcCXiYdnbv3lvHbGRmc/aD9HAW8v2J0JfCP1rFrOJRjhpqKNJi/I885/V09c16GCxWR/YdfJTSGQ5T0ikzGo=@vger.kernel.org X-Gm-Message-State: AOJu0YzSO+8miekeKdSX4aplyMQ9gff8aK0GuZJkcveCDS5e3qPiSmwQ wDSW5iS0qA9oTzUqt3pbR0IvC1PNIFWF4zFfz8OZo90hLdNcYoV8R8xCyZKWAnvGgylgoq+AzpN 7SKO+C4UVVtZCNQ== X-Received: from pgc7.prod.google.com ([2002:a05:6a02:2f87:b0:c6e:21b7:bfd0]) (user=jmattson job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a20:3d8d:b0:35f:cfb:1ee3 with SMTP id adf61e73a8af0-394484b2496mr3361847637.25.1770911954124; Thu, 12 Feb 2026 07:59:14 -0800 (PST) Date: Thu, 12 Feb 2026 07:58:49 -0800 In-Reply-To: <20260212155905.3448571-1-jmattson@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260212155905.3448571-1-jmattson@google.com> X-Mailer: git-send-email 2.53.0.239.g8d8fc8a987-goog Message-ID: <20260212155905.3448571-2-jmattson@google.com> Subject: [PATCH v4 1/8] KVM: x86: nSVM: Clear VMCB_NPT clean bit when updating hPAT from guest mode 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 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 | 9 +++++---- 3 files changed, 7 insertions(+), 7 deletions(-) diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index d80b1bde6630..b72a1f3c4144 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -707,7 +707,7 @@ 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 void nested_vmcb02_prepare_save(struct vcpu_svm *svm) diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 364915f42e13..529cbac57814 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -2924,10 +2924,9 @@ 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 0bb93879abfe..9850ed01e16e 100644 --- a/arch/x86/kvm/svm/svm.h +++ b/arch/x86/kvm/svm/svm.h @@ -434,14 +434,15 @@ static inline void vmcb_mark_dirty(struct vmcb *vmcb,= int bit) vmcb->control.clean &=3D ~(1 << bit); } =20 -static inline bool vmcb_is_dirty(struct vmcb *vmcb, int bit) +static inline bool vmcb12_is_dirty(struct vmcb_ctrl_area_cached *control, = int bit) { - return !test_bit(bit, (unsigned long *)&vmcb->control.clean); + return !test_bit(bit, (unsigned long *)&control->clean); } =20 -static inline bool vmcb12_is_dirty(struct vmcb_ctrl_area_cached *control, = int bit) +static inline void vmcb_set_gpat(struct vmcb *vmcb, u64 data) { - return !test_bit(bit, (unsigned long *)&control->clean); + vmcb->save.g_pat =3D data; + vmcb_mark_dirty(vmcb, VMCB_NPT); } =20 static __always_inline struct vcpu_svm *to_svm(struct kvm_vcpu *vcpu) --=20 2.53.0.239.g8d8fc8a987-goog