From: Chao Gao <chao.gao@intel.com>
To: Sean Christopherson <seanjc@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>,
Vitaly Kuznetsov <vkuznets@redhat.com>, <kvm@vger.kernel.org>,
<linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 01/12] KVM: x86: Add a framework for enabling KVM-governed x86 features
Date: Fri, 30 Jun 2023 16:01:38 +0800 [thread overview]
Message-ID: <ZJ6L4oWE9refbXnX@chao-email> (raw)
In-Reply-To: <20230217231022.816138-2-seanjc@google.com>
On Fri, Feb 17, 2023 at 03:10:11PM -0800, Sean Christopherson wrote:
>+static __always_inline void kvm_governed_feature_set(struct kvm_vcpu *vcpu,
>+ unsigned int x86_feature)
>+{
>+ BUILD_BUG_ON(KVM_NR_GOVERNED_FEATURES >
>+ sizeof(vcpu->arch.governed_features.enabled) * BITS_PER_BYTE);
>+
>+ vcpu->arch.governed_features.enabled |= kvm_governed_feature_bit(x86_feature);
>+}
>+
>+static __always_inline void kvm_governed_feature_check_and_set(struct kvm_vcpu *vcpu,
>+ unsigned int x86_feature)
>+{
>+ if (guest_cpuid_has(vcpu, x86_feature))
Most callers in this series are conditional on either boot_cpu_has() or some
local variables. Can we convert them to kvm_cpu_cap_has() and incorporate them
within this function? i.e.,
if (kvm_cpu_cap_has(x86_feature) && guest_cpuid_has(vcpu, x86_feature))
The benefits of doing so are
1. callers needn't repeat
if (kvm_cpu_cap_has(x86_feature))
kvm_governed_feature_check_and_set(x86_feature)
2. this fits the idea better that guests can use a governed feature only if host
supports it _and_ QEMU exposes it to the guest.
>+ kvm_governed_feature_set(vcpu, x86_feature);
>+}
>+
next prev parent reply other threads:[~2023-06-30 8:02 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-02-17 23:10 [PATCH 00/12] KVM: x86: Add "governed" X86_FEATURE framework Sean Christopherson
2023-02-17 23:10 ` [PATCH 01/12] KVM: x86: Add a framework for enabling KVM-governed x86 features Sean Christopherson
2023-02-21 17:12 ` Vitaly Kuznetsov
2023-06-29 2:40 ` Binbin Wu
2023-06-29 16:26 ` Sean Christopherson
2023-06-30 8:01 ` Chao Gao [this message]
2023-06-30 15:31 ` Sean Christopherson
2023-02-17 23:10 ` [PATCH 02/12] KVM: x86/mmu: Use KVM-governed feature framework to track "GBPAGES enabled" Sean Christopherson
2023-02-17 23:10 ` [PATCH 03/12] KVM: VMX: Recompute "XSAVES enabled" only after CPUID update Sean Christopherson
2023-02-17 23:10 ` [PATCH 04/12] KVM: VMX: Rename XSAVES control to follow KVM's preferred "ENABLE_XYZ" Sean Christopherson
2023-02-17 23:10 ` [PATCH 05/12] KVM: x86: Use KVM-governed feature framework to track "XSAVES enabled" Sean Christopherson
2023-02-21 14:56 ` Yu Zhang
2023-02-22 18:56 ` Sean Christopherson
2023-02-24 9:54 ` Yu Zhang
2023-02-17 23:10 ` [PATCH 06/12] KVM: nSVM: Use KVM-governed feature framework to track "NRIPS enabled" Sean Christopherson
2023-02-17 23:10 ` [PATCH 07/12] KVM: nSVM: Use KVM-governed feature framework to track "TSC scaling enabled" Sean Christopherson
2023-02-17 23:10 ` [PATCH 08/12] KVM: nSVM: Use KVM-governed feature framework to track "vVM{SAVE,LOAD} enabled" Sean Christopherson
2023-02-21 15:23 ` Yu Zhang
2023-02-21 15:33 ` Yu Zhang
2023-02-21 23:48 ` Sean Christopherson
2023-02-22 6:49 ` Yu Zhang
2023-02-22 16:39 ` Sean Christopherson
2023-02-24 9:25 ` Yu Zhang
2023-02-24 16:16 ` Sean Christopherson
[not found] ` <20230227065437.j7f7rfadut532fud@linux.intel.com>
2023-03-07 16:32 ` Sean Christopherson
2023-06-29 16:50 ` Sean Christopherson
2023-06-30 10:00 ` Yu Zhang
2023-02-17 23:10 ` [PATCH 09/12] KVM: nSVM: Use KVM-governed feature framework to track "LBRv enabled" Sean Christopherson
2023-02-17 23:10 ` [PATCH 10/12] KVM: nSVM: Use KVM-governed feature framework to track "Pause Filter enabled" Sean Christopherson
2023-02-17 23:10 ` [PATCH 11/12] KVM: nSVM: Use KVM-governed feature framework to track "vGIF enabled" Sean Christopherson
2023-02-17 23:10 ` [PATCH 12/12] KVM: x86: Disallow guest CPUID lookups when IRQs are disabled Sean Christopherson
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