From nobody Tue Sep 16 05:44:10 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) client-ip=192.237.175.120; envelope-from=xen-devel-bounces@lists.xenproject.org; helo=lists.xenproject.org; Authentication-Results: mx.zohomail.com; spf=pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org; dmarc=fail(p=quarantine dis=quarantine) header.from=amazon.com Return-Path: Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) by mx.zohomail.com with SMTPS id 1673001415420430.191637997861; Fri, 6 Jan 2023 02:36:55 -0800 (PST) Received: from list by lists.xenproject.org with outflank-mailman.472422.732637 (Exim 4.92) (envelope-from ) id 1pDk5Q-00050f-6Q; Fri, 06 Jan 2023 10:36:32 +0000 Received: by outflank-mailman (output) from mailman id 472422.732637; Fri, 06 Jan 2023 10:36:32 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1pDk5Q-00050W-3L; Fri, 06 Jan 2023 10:36:32 +0000 Received: by outflank-mailman (input) for mailman id 472422; Fri, 06 Jan 2023 10:36:31 +0000 Received: from mail.xenproject.org ([104.130.215.37]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1pDk5P-000500-5n for xen-devel@lists.xenproject.org; Fri, 06 Jan 2023 10:36:31 +0000 Received: from xenbits.xenproject.org ([104.239.192.120]) by mail.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1pDk5K-0003o2-SY; Fri, 06 Jan 2023 10:36:26 +0000 Received: from 54-240-197-227.amazon.com ([54.240.197.227] helo=debian.cbg12.amazon.com) by xenbits.xenproject.org with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1pDk5K-0001wX-Ir; Fri, 06 Jan 2023 10:36:26 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" From: Paul Durrant To: x86@kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org, linux-kernel@vger.kernel.org Cc: Paul Durrant , Sean Christopherson , Paolo Bonzini , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , David Woodhouse Subject: [PATCH v7 1/2] KVM: x86/cpuid: generalize kvm_update_kvm_cpuid_base() and also capture limit Date: Fri, 6 Jan 2023 10:35:59 +0000 Message-Id: <20230106103600.528-2-pdurrant@amazon.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20230106103600.528-1-pdurrant@amazon.com> References: <20230106103600.528-1-pdurrant@amazon.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ZM-MESSAGEID: 1673001418158100001 Content-Type: text/plain; charset="utf-8" A subsequent patch will need to acquire the CPUID leaf range for emulated Xen so explicitly pass the signature of the hypervisor we're interested in to the new function. Also introduce a new kvm_hypervisor_cpuid structure so we can neatly store both the base and limit leaf indices. Signed-off-by: Paul Durrant Reviewed-by: David Woodhouse --- Cc: Sean Christopherson Cc: Paolo Bonzini Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: Dave Hansen Cc: David Woodhouse v7: - Morph kvm_update_hypervisor_cpuid() into kvm_get_hypervisor_cpuid() - Place the definition of struct kvm_hypervisor_cpuid to avoid churn in patch #2. v6: - New in this version --- arch/x86/include/asm/kvm_host.h | 7 ++++++- arch/x86/kvm/cpuid.c | 24 +++++++++++++----------- 2 files changed, 19 insertions(+), 12 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_hos= t.h index c70690b2c82d..85cbe4571ac9 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -678,6 +678,11 @@ struct kvm_vcpu_hv { } nested; }; =20 +struct kvm_hypervisor_cpuid { + u32 base; + u32 limit; +}; + /* Xen HVM per vcpu emulation context */ struct kvm_vcpu_xen { u64 hypercall_rip; @@ -826,7 +831,7 @@ struct kvm_vcpu_arch { =20 int cpuid_nent; struct kvm_cpuid_entry2 *cpuid_entries; - u32 kvm_cpuid_base; + struct kvm_hypervisor_cpuid kvm_cpuid; =20 u64 reserved_gpa_bits; int maxphyaddr; diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 69768e4d53a6..db5a4d38fcd0 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -180,15 +180,15 @@ static int kvm_cpuid_check_equal(struct kvm_vcpu *vcp= u, struct kvm_cpuid_entry2 return 0; } =20 -static void kvm_update_kvm_cpuid_base(struct kvm_vcpu *vcpu) +static struct kvm_hypervisor_cpuid kvm_get_hypervisor_cpuid(struct kvm_vcp= u *vcpu, + const char *sig) { - u32 function; + struct kvm_hypervisor_cpuid cpuid =3D {}; struct kvm_cpuid_entry2 *entry; + u32 base; =20 - vcpu->arch.kvm_cpuid_base =3D 0; - - for_each_possible_hypervisor_cpuid_base(function) { - entry =3D kvm_find_cpuid_entry(vcpu, function); + for_each_possible_hypervisor_cpuid_base(base) { + entry =3D kvm_find_cpuid_entry(vcpu, base); =20 if (entry) { u32 signature[3]; @@ -197,19 +197,21 @@ static void kvm_update_kvm_cpuid_base(struct kvm_vcpu= *vcpu) signature[1] =3D entry->ecx; signature[2] =3D entry->edx; =20 - BUILD_BUG_ON(sizeof(signature) > sizeof(KVM_SIGNATURE)); - if (!memcmp(signature, KVM_SIGNATURE, sizeof(signature))) { - vcpu->arch.kvm_cpuid_base =3D function; + if (!memcmp(signature, sig, sizeof(signature))) { + cpuid.base =3D base; + cpuid.limit =3D entry->eax; break; } } } + + return cpuid; } =20 static struct kvm_cpuid_entry2 *__kvm_find_kvm_cpuid_features(struct kvm_v= cpu *vcpu, struct kvm_cpuid_entry2 *entries, int nent) { - u32 base =3D vcpu->arch.kvm_cpuid_base; + u32 base =3D vcpu->arch.kvm_cpuid.base; =20 if (!base) return NULL; @@ -439,7 +441,7 @@ static int kvm_set_cpuid(struct kvm_vcpu *vcpu, struct = kvm_cpuid_entry2 *e2, vcpu->arch.cpuid_entries =3D e2; vcpu->arch.cpuid_nent =3D nent; =20 - kvm_update_kvm_cpuid_base(vcpu); + vcpu->arch.kvm_cpuid =3D kvm_get_hypervisor_cpuid(vcpu, KVM_SIGNATURE); kvm_vcpu_after_set_cpuid(vcpu); =20 return 0; --=20 2.20.1