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From: Like Xu <like.xu.linux@gmail.com>
To: Sean Christopherson <seanjc@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>,
	kvm@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH v6 04/10] KVM: x86: Explicitly zero cpuid "0xa" leaf when PMU is disabled
Date: Tue, 30 May 2023 14:04:17 +0800	[thread overview]
Message-ID: <20230530060423.32361-5-likexu@tencent.com> (raw)
In-Reply-To: <20230530060423.32361-1-likexu@tencent.com>

From: Like Xu <likexu@tencent.com>

Add an explicit !enable_pmu check as relying on kvm_pmu_cap to be
zeroed isn't obvious. Although when !enable_pmu, KVM will have
zero-padded kvm_pmu_cap to do subsequent CPUID leaf assignments.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Like Xu <likexu@tencent.com>
---
 arch/x86/kvm/cpuid.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 0c9660a07b23..61bc71882f07 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -948,7 +948,7 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function)
 		union cpuid10_eax eax;
 		union cpuid10_edx edx;
 
-		if (!static_cpu_has(X86_FEATURE_ARCH_PERFMON)) {
+		if (!enable_pmu || !static_cpu_has(X86_FEATURE_ARCH_PERFMON)) {
 			entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
 			break;
 		}
-- 
2.40.1


  parent reply	other threads:[~2023-05-30  6:05 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-05-30  6:04 [PATCH v6 00/10] KVM: x86: Add AMD Guest PerfMonV2 PMU support Like Xu
2023-05-30  6:04 ` [PATCH v6 01/10] KVM: x86/pmu: Expose reprogram_counters() in pmu.h Like Xu
2023-05-30  6:04 ` [PATCH v6 02/10] KVM: x86/pmu: Return #GP if user sets the GLOBAL_STATUS reserved bits Like Xu
2023-06-02 21:59   ` Sean Christopherson
2023-05-30  6:04 ` [PATCH v6 03/10] KVM: x86/pmu: Make part of the Intel v2 PMU MSRs handling x86 generic Like Xu
2023-06-02 23:23   ` Sean Christopherson
2023-05-30  6:04 ` Like Xu [this message]
2023-05-30  6:04 ` [PATCH v6 05/10] KVM: x86/pmu: Disable vPMU if the minimum num of counters isn't met Like Xu
2023-06-02  0:50   ` Sean Christopherson
2023-05-30  6:04 ` [PATCH v6 06/10] KVM: x86/pmu: Forget PERFCTR_CORE if the min " Like Xu
2023-05-30  6:04 ` [PATCH v6 07/10] KVM: x86/pmu: Constrain the num of guest counters with kvm_pmu_cap Like Xu
2023-05-30  6:04 ` [PATCH v6 08/10] KVM: x86/cpuid: Add a KVM-only leaf to redirect AMD PerfMonV2 flag Like Xu
2023-05-30  6:04 ` [PATCH v6 09/10] KVM: x86/svm/pmu: Add AMD PerfMonV2 support Like Xu
2023-05-30  6:04 ` [PATCH v6 10/10] KVM: x86/cpuid: Add AMD CPUID ExtPerfMonAndDbg leaf 0x80000022 Like Xu

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