| Message ID | 1634631160-67276-2-git-send-email-wanpengli@tencent.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v3,1/3] KVM: emulate: Don't inject #GP when emulating RDMPC if CR0.PE=0 | expand |
On 19/10/21 10:12, Wanpeng Li wrote: > From: Wanpeng Li <wanpengli@tencent.com> > > SDM section 18.2.3 mentioned that: > > "IA32_PERF_GLOBAL_OVF_CTL MSR allows software to clear overflow indicator(s) of > any general-purpose or fixed-function counters via a single WRMSR." > > It is R/W mentioned by SDM, we read this msr on bare-metal during perf testing, > the value is always 0 for ICX/SKX boxes on hands. Let's fill get_msr > MSR_CORE_PERF_GLOBAL_OVF_CTRL w/ 0 as hardware behavior and drop > global_ovf_ctrl variable. > > Tested-by: Like Xu <likexu@tencent.com> > Signed-off-by: Wanpeng Li <wanpengli@tencent.com> > --- > Btw, xen also fills get_msr MSR_CORE_PERF_GLOBAL_OVF_CTRL w/ 0. > v1 -> v2: > * drop 'u64 global_ovf_ctrl' directly > > arch/x86/include/asm/kvm_host.h | 1 - > arch/x86/kvm/vmx/pmu_intel.c | 6 ++---- > 2 files changed, 2 insertions(+), 5 deletions(-) > > diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h > index f8f48a7ec577..7aaac918e992 100644 > --- a/arch/x86/include/asm/kvm_host.h > +++ b/arch/x86/include/asm/kvm_host.h > @@ -499,7 +499,6 @@ struct kvm_pmu { > u64 fixed_ctr_ctrl; > u64 global_ctrl; > u64 global_status; > - u64 global_ovf_ctrl; > u64 counter_bitmask[2]; > u64 global_ctrl_mask; > u64 global_ovf_ctrl_mask; > diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c > index 10cc4f65c4ef..b8e0d21b7c8a 100644 > --- a/arch/x86/kvm/vmx/pmu_intel.c > +++ b/arch/x86/kvm/vmx/pmu_intel.c > @@ -365,7 +365,7 @@ static int intel_pmu_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) > msr_info->data = pmu->global_ctrl; > return 0; > case MSR_CORE_PERF_GLOBAL_OVF_CTRL: > - msr_info->data = pmu->global_ovf_ctrl; > + msr_info->data = 0; > return 0; > default: > if ((pmc = get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0)) || > @@ -423,7 +423,6 @@ static int intel_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) > if (!(data & pmu->global_ovf_ctrl_mask)) { > if (!msr_info->host_initiated) > pmu->global_status &= ~data; > - pmu->global_ovf_ctrl = data; > return 0; > } > break; > @@ -588,8 +587,7 @@ static void intel_pmu_reset(struct kvm_vcpu *vcpu) > pmc->counter = 0; > } > > - pmu->fixed_ctr_ctrl = pmu->global_ctrl = pmu->global_status = > - pmu->global_ovf_ctrl = 0; > + pmu->fixed_ctr_ctrl = pmu->global_ctrl = pmu->global_status = 0; > > intel_pmu_release_guest_lbr_event(vcpu); > } > Queued, thanks. Paolo
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index f8f48a7ec577..7aaac918e992 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -499,7 +499,6 @@ struct kvm_pmu { u64 fixed_ctr_ctrl; u64 global_ctrl; u64 global_status; - u64 global_ovf_ctrl; u64 counter_bitmask[2]; u64 global_ctrl_mask; u64 global_ovf_ctrl_mask; diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c index 10cc4f65c4ef..b8e0d21b7c8a 100644 --- a/arch/x86/kvm/vmx/pmu_intel.c +++ b/arch/x86/kvm/vmx/pmu_intel.c @@ -365,7 +365,7 @@ static int intel_pmu_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) msr_info->data = pmu->global_ctrl; return 0; case MSR_CORE_PERF_GLOBAL_OVF_CTRL: - msr_info->data = pmu->global_ovf_ctrl; + msr_info->data = 0; return 0; default: if ((pmc = get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0)) || @@ -423,7 +423,6 @@ static int intel_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) if (!(data & pmu->global_ovf_ctrl_mask)) { if (!msr_info->host_initiated) pmu->global_status &= ~data; - pmu->global_ovf_ctrl = data; return 0; } break; @@ -588,8 +587,7 @@ static void intel_pmu_reset(struct kvm_vcpu *vcpu) pmc->counter = 0; } - pmu->fixed_ctr_ctrl = pmu->global_ctrl = pmu->global_status = - pmu->global_ovf_ctrl = 0; + pmu->fixed_ctr_ctrl = pmu->global_ctrl = pmu->global_status = 0; intel_pmu_release_guest_lbr_event(vcpu); }