From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F011E2FF14D; Tue, 24 Feb 2026 22:34:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771972462; cv=none; b=UDkGcDi/Cs5JVmnTK3ePCwWjhi6g9+0nPTwJ5CFQGc2y6AgDafqmqAS746PnLXF33dPzZcbK3qV1v89i8U2NN2d8alrG9OB712aQQZqHt5+5BBR/RhsdePfpMI0ebInw5hZE7fl7ypt8mthbBQP+xQesdcuYIilbXg8JvQKDH/U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771972462; c=relaxed/simple; bh=Vhp3vuWokN317wHEb9O9UL3ilPmfH+y4ZZA1i44uBXg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=YwPe9cisE/AXEJdox5xjh5HZbL7lJ932gnHH+iJAyCLweqdlVoNT4ufQpdHsO7A6Qqxa+beJEuMqv5M8NaDWYZVkhTlOtqqgFdsBmUvwjuaEdHzzh78b79cuUzO1HrV2osksO+xgdslBNyckQI+IuLaRII+b6I/m/SNbEixr2J4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=rdEt87CW; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="rdEt87CW" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 96E8FC19423; Tue, 24 Feb 2026 22:34:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1771972461; bh=Vhp3vuWokN317wHEb9O9UL3ilPmfH+y4ZZA1i44uBXg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rdEt87CWIFfBIlDirRh7TT4naJikdwC6O5lZdYxe05MXCamybiAz2YU/TPbWwSqTR neMf7Cj6EXr18sskbWLV7G6yzL5nCdxN70P41B8qKDun4dgkS8Vmc3aaYPCgIY41hn Rs/gcVUK79cRSbXM4cyNzl+Ae3RHdAGoKYV8cm3/eyOhueLhxCCg2RKqD/+OVSzadW BwvbamYKK8RQaASYhRDF8JRBzvocv9ot3JuyhvnJhOrB/en9C/0n6Kxk0YRUSeH4HQ BJW33ERf7PYRjnOerXRP9CwvCNR+F28jT8s+ozpqxIkWggX0kb3MtY2QPd2WEPk9u7 xmn/DWKuiAPPA== From: Yosry Ahmed To: Sean Christopherson Cc: Paolo Bonzini , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Yosry Ahmed , stable@vger.kernel.org Subject: [PATCH v6 01/31] KVM: nSVM: Avoid clearing VMCB_LBR in vmcb12 Date: Tue, 24 Feb 2026 22:33:35 +0000 Message-ID: <20260224223405.3270433-2-yosry@kernel.org> X-Mailer: git-send-email 2.53.0.414.gf7e9f6c205-goog In-Reply-To: <20260224223405.3270433-1-yosry@kernel.org> References: <20260224223405.3270433-1-yosry@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit svm_copy_lbrs() always marks VMCB_LBR dirty in the destination VMCB. However, nested_svm_vmexit() uses it to copy LBRs to vmcb12, and clearing clean bits in vmcb12 is not architecturally defined. Move vmcb_mark_dirty() to callers and drop it for vmcb12. This also facilitates incoming refactoring that does not pass the entire VMCB to svm_copy_lbrs(). Fixes: d20c796ca370 ("KVM: x86: nSVM: implement nested LBR virtualization") Cc: stable@vger.kernel.org Signed-off-by: Yosry Ahmed --- arch/x86/kvm/svm/nested.c | 7 +++++-- arch/x86/kvm/svm/svm.c | 2 -- 2 files changed, 5 insertions(+), 4 deletions(-) diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index de90b104a0dd5..a31f3be1e16ec 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -714,6 +714,7 @@ static void nested_vmcb02_prepare_save(struct vcpu_svm *svm, struct vmcb *vmcb12 } else { svm_copy_lbrs(vmcb02, vmcb01); } + vmcb_mark_dirty(vmcb02, VMCB_LBR); svm_update_lbrv(&svm->vcpu); } @@ -1232,10 +1233,12 @@ int nested_svm_vmexit(struct vcpu_svm *svm) kvm_make_request(KVM_REQ_EVENT, &svm->vcpu); if (unlikely(guest_cpu_cap_has(vcpu, X86_FEATURE_LBRV) && - (svm->nested.ctl.virt_ext & LBR_CTL_ENABLE_MASK))) + (svm->nested.ctl.virt_ext & LBR_CTL_ENABLE_MASK))) { svm_copy_lbrs(vmcb12, vmcb02); - else + } else { svm_copy_lbrs(vmcb01, vmcb02); + vmcb_mark_dirty(vmcb01, VMCB_LBR); + } svm_update_lbrv(vcpu); diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 8f8bc863e2143..a2452b8ec49db 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -848,8 +848,6 @@ void svm_copy_lbrs(struct vmcb *to_vmcb, struct vmcb *from_vmcb) to_vmcb->save.br_to = from_vmcb->save.br_to; to_vmcb->save.last_excp_from = from_vmcb->save.last_excp_from; to_vmcb->save.last_excp_to = from_vmcb->save.last_excp_to; - - vmcb_mark_dirty(to_vmcb, VMCB_LBR); } static void __svm_enable_lbrv(struct kvm_vcpu *vcpu) -- 2.53.0.414.gf7e9f6c205-goog