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Peter Anvin" , Andy Lutomirski , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Sean Christopherson , Paolo Bonzini Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, kvm@vger.kernel.org, loongarch@lists.linux.dev, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Kan Liang , Yongwei Ma , Mingwei Zhang , Xiong Zhang , Sandipan Das , Dapeng Mi Content-Type: text/plain; charset="UTF-8" Rework the MSR_FILTER_CHANGED request into a more generic RECALC_INTERCEPTS request, and expand the responsibilities of vendor code to recalculate all intercepts that vary based on userspace input, e.g. instruction intercepts that are tied to guest CPUID. Providing a generic recalc request will allow the upcoming mediated PMU support to trigger a recalc when PMU features, e.g. PERF_CAPABILITIES, are set by userspace, without having to make multiple calls to/from PMU code. As a bonus, using a request will effectively coalesce recalcs, e.g. will reduce the number of recalcs for normal usage from 3+ to 1 (vCPU create, set CPUID, set PERF_CAPABILITIES (Intel only), set filter). The downside is that MSR filter changes that are done in isolation will do a small amount of unnecessary work, but that's already a relatively slow path, and the cost of recalculating instruction intercepts is negligible. Signed-off-by: Sean Christopherson --- arch/x86/include/asm/kvm-x86-ops.h | 2 +- arch/x86/include/asm/kvm_host.h | 4 ++-- arch/x86/kvm/svm/svm.c | 8 ++++---- arch/x86/kvm/vmx/main.c | 14 +++++++------- arch/x86/kvm/vmx/vmx.c | 9 +++++++-- arch/x86/kvm/vmx/x86_ops.h | 2 +- arch/x86/kvm/x86.c | 15 +++++++-------- 7 files changed, 29 insertions(+), 25 deletions(-) diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h index 18a5c3119e1a..7c240e23bd52 100644 --- a/arch/x86/include/asm/kvm-x86-ops.h +++ b/arch/x86/include/asm/kvm-x86-ops.h @@ -138,7 +138,7 @@ KVM_X86_OP(check_emulate_instruction) KVM_X86_OP(apic_init_signal_blocked) KVM_X86_OP_OPTIONAL(enable_l2_tlb_flush) KVM_X86_OP_OPTIONAL(migrate_timers) -KVM_X86_OP(recalc_msr_intercepts) +KVM_X86_OP(recalc_intercepts) KVM_X86_OP(complete_emulated_msr) KVM_X86_OP(vcpu_deliver_sipi_vector) KVM_X86_OP_OPTIONAL_RET0(vcpu_get_apicv_inhibit_reasons); diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index ff0d753e2b07..b891bd92fc83 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -120,7 +120,7 @@ #define KVM_REQ_TLB_FLUSH_GUEST \ KVM_ARCH_REQ_FLAGS(27, KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP) #define KVM_REQ_APF_READY KVM_ARCH_REQ(28) -#define KVM_REQ_MSR_FILTER_CHANGED KVM_ARCH_REQ(29) +#define KVM_REQ_RECALC_INTERCEPTS KVM_ARCH_REQ(29) #define KVM_REQ_UPDATE_CPU_DIRTY_LOGGING \ KVM_ARCH_REQ_FLAGS(30, KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP) #define KVM_REQ_MMU_FREE_OBSOLETE_ROOTS \ @@ -1912,7 +1912,7 @@ struct kvm_x86_ops { int (*enable_l2_tlb_flush)(struct kvm_vcpu *vcpu); void (*migrate_timers)(struct kvm_vcpu *vcpu); - void (*recalc_msr_intercepts)(struct kvm_vcpu *vcpu); + void (*recalc_intercepts)(struct kvm_vcpu *vcpu); int (*complete_emulated_msr)(struct kvm_vcpu *vcpu, int err); void (*vcpu_deliver_sipi_vector)(struct kvm_vcpu *vcpu, u8 vector); diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index f7e1e665a826..3d9dcc66a407 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -1077,7 +1077,7 @@ static void svm_recalc_instruction_intercepts(struct kvm_vcpu *vcpu) } } -static void svm_recalc_intercepts_after_set_cpuid(struct kvm_vcpu *vcpu) +static void svm_recalc_intercepts(struct kvm_vcpu *vcpu) { svm_recalc_instruction_intercepts(vcpu); svm_recalc_msr_intercepts(vcpu); @@ -1225,7 +1225,7 @@ static void init_vmcb(struct kvm_vcpu *vcpu) svm_hv_init_vmcb(vmcb); - svm_recalc_intercepts_after_set_cpuid(vcpu); + svm_recalc_intercepts(vcpu); vmcb_mark_all_dirty(vmcb); @@ -4479,7 +4479,7 @@ static void svm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu) if (sev_guest(vcpu->kvm)) sev_vcpu_after_set_cpuid(svm); - svm_recalc_intercepts_after_set_cpuid(vcpu); + svm_recalc_intercepts(vcpu); } static bool svm_has_wbinvd_exit(void) @@ -5181,7 +5181,7 @@ static struct kvm_x86_ops svm_x86_ops __initdata = { .apic_init_signal_blocked = svm_apic_init_signal_blocked, - .recalc_msr_intercepts = svm_recalc_msr_intercepts, + .recalc_intercepts = svm_recalc_intercepts, .complete_emulated_msr = svm_complete_emulated_msr, .vcpu_deliver_sipi_vector = svm_vcpu_deliver_sipi_vector, diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c index dbab1c15b0cd..68dcafd177a8 100644 --- a/arch/x86/kvm/vmx/main.c +++ b/arch/x86/kvm/vmx/main.c @@ -188,18 +188,18 @@ static int vt_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) return vmx_get_msr(vcpu, msr_info); } -static void vt_recalc_msr_intercepts(struct kvm_vcpu *vcpu) +static void vt_recalc_intercepts(struct kvm_vcpu *vcpu) { /* - * TDX doesn't allow VMM to configure interception of MSR accesses. - * TDX guest requests MSR accesses by calling TDVMCALL. The MSR - * filters will be applied when handling the TDVMCALL for RDMSR/WRMSR - * if the userspace has set any. + * TDX doesn't allow VMM to configure interception of instructions or + * MSR accesses. TDX guest requests MSR accesses by calling TDVMCALL. + * The MSR filters will be applied when handling the TDVMCALL for + * RDMSR/WRMSR if the userspace has set any. */ if (is_td_vcpu(vcpu)) return; - vmx_recalc_msr_intercepts(vcpu); + vmx_recalc_intercepts(vcpu); } static int vt_complete_emulated_msr(struct kvm_vcpu *vcpu, int err) @@ -995,7 +995,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = { .apic_init_signal_blocked = vt_op(apic_init_signal_blocked), .migrate_timers = vmx_migrate_timers, - .recalc_msr_intercepts = vt_op(recalc_msr_intercepts), + .recalc_intercepts = vt_op(recalc_intercepts), .complete_emulated_msr = vt_op(complete_emulated_msr), .vcpu_deliver_sipi_vector = kvm_vcpu_deliver_sipi_vector, diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 93b87f9e6dfd..2244ca074e9d 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -4068,7 +4068,7 @@ void pt_update_intercept_for_msr(struct kvm_vcpu *vcpu) } } -void vmx_recalc_msr_intercepts(struct kvm_vcpu *vcpu) +static void vmx_recalc_msr_intercepts(struct kvm_vcpu *vcpu) { if (!cpu_has_vmx_msr_bitmap()) return; @@ -4121,6 +4121,11 @@ void vmx_recalc_msr_intercepts(struct kvm_vcpu *vcpu) */ } +void vmx_recalc_intercepts(struct kvm_vcpu *vcpu) +{ + vmx_recalc_msr_intercepts(vcpu); +} + static int vmx_deliver_nested_posted_interrupt(struct kvm_vcpu *vcpu, int vector) { @@ -7778,7 +7783,7 @@ void vmx_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu) ~FEAT_CTL_SGX_LC_ENABLED; /* Recalc MSR interception to account for feature changes. */ - vmx_recalc_msr_intercepts(vcpu); + vmx_recalc_intercepts(vcpu); /* Refresh #PF interception to account for MAXPHYADDR changes. */ vmx_update_exception_bitmap(vcpu); diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h index 2b3424f638db..2c590ff44ced 100644 --- a/arch/x86/kvm/vmx/x86_ops.h +++ b/arch/x86/kvm/vmx/x86_ops.h @@ -52,7 +52,7 @@ void vmx_deliver_interrupt(struct kvm_lapic *apic, int delivery_mode, int trig_mode, int vector); void vmx_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu); bool vmx_has_emulated_msr(struct kvm *kvm, u32 index); -void vmx_recalc_msr_intercepts(struct kvm_vcpu *vcpu); +void vmx_recalc_intercepts(struct kvm_vcpu *vcpu); void vmx_prepare_switch_to_guest(struct kvm_vcpu *vcpu); void vmx_update_exception_bitmap(struct kvm_vcpu *vcpu); int vmx_get_feature_msr(u32 msr, u64 *data); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 2c34dd3f0222..69f5d9deb75f 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -6742,7 +6742,11 @@ static int kvm_vm_ioctl_set_msr_filter(struct kvm *kvm, kvm_free_msr_filter(old_filter); - kvm_make_all_cpus_request(kvm, KVM_REQ_MSR_FILTER_CHANGED); + /* + * Recalc MSR intercepts as userspace may want to intercept accesses to + * MSRs that KVM would otherwise pass through to the guest. + */ + kvm_make_all_cpus_request(kvm, KVM_REQ_RECALC_INTERCEPTS); return 0; } @@ -10765,13 +10769,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) if (kvm_check_request(KVM_REQ_APF_READY, vcpu)) kvm_check_async_pf_completion(vcpu); - /* - * Recalc MSR intercepts as userspace may want to intercept - * accesses to MSRs that KVM would otherwise pass through to - * the guest. - */ - if (kvm_check_request(KVM_REQ_MSR_FILTER_CHANGED, vcpu)) - kvm_x86_call(recalc_msr_intercepts)(vcpu); + if (kvm_check_request(KVM_REQ_RECALC_INTERCEPTS, vcpu)) + kvm_x86_call(recalc_intercepts)(vcpu); if (kvm_check_request(KVM_REQ_UPDATE_CPU_DIRTY_LOGGING, vcpu)) kvm_x86_call(update_cpu_dirty_logging)(vcpu); -- 2.50.1.565.gc32cd1483b-goog