Hi Drew, On 6/21/19 6:34 PM, Andrew Jones wrote: > We first convert the pmu property from a static property to one with > its own accessors. Then we use the set accessor to check if the PMU is > supported when using KVM. Indeed a 32-bit KVM host does not support > the PMU, so this check will catch an attempt to use it at property-set > time. > > Signed-off-by: Andrew Jones <drjo...@redhat.com> > --- > target/arm/cpu.c | 30 +++++++++++++++++++++++++----- > target/arm/kvm.c | 9 +++++++++ > target/arm/kvm_arm.h | 13 +++++++++++++ > 3 files changed, 47 insertions(+), 5 deletions(-) > > diff --git a/target/arm/cpu.c b/target/arm/cpu.c > index 376db154f008..858f668d226e 100644 > --- a/target/arm/cpu.c > +++ b/target/arm/cpu.c > @@ -759,10 +759,6 @@ static Property arm_cpu_has_el3_property = > static Property arm_cpu_cfgend_property = > DEFINE_PROP_BOOL("cfgend", ARMCPU, cfgend, false); > > -/* use property name "pmu" to match other archs and virt tools */ > -static Property arm_cpu_has_pmu_property = > - DEFINE_PROP_BOOL("pmu", ARMCPU, has_pmu, true); > - > static Property arm_cpu_has_vfp_property = > DEFINE_PROP_BOOL("vfp", ARMCPU, has_vfp, true); > > @@ -785,6 +781,29 @@ static Property arm_cpu_pmsav7_dregion_property = > pmsav7_dregion, > qdev_prop_uint32, uint32_t); > > +static bool arm_get_pmu(Object *obj, Error **errp) > +{ > + ARMCPU *cpu = ARM_CPU(obj); > + > + return cpu->has_pmu; > +} > + > +static void arm_set_pmu(Object *obj, bool value, Error **errp) > +{ > + ARMCPU *cpu = ARM_CPU(obj); > + > + if (value) { > + if (kvm_enabled() && !kvm_arm_pmu_supported(CPU(cpu))) { > + error_setg(errp, "'pmu' feature not supported by KVM on this > host"); > + return; > + } > + set_feature(&cpu->env, ARM_FEATURE_PMU); > + } else { > + unset_feature(&cpu->env, ARM_FEATURE_PMU); > + } > + cpu->has_pmu = value; > +} > + > static void arm_get_init_svtor(Object *obj, Visitor *v, const char *name, > void *opaque, Error **errp) > { > @@ -859,7 +878,8 @@ void arm_cpu_post_init(Object *obj) > } > > if (arm_feature(&cpu->env, ARM_FEATURE_PMU)) { > - qdev_property_add_static(DEVICE(obj), &arm_cpu_has_pmu_property, > + cpu->has_pmu = true; > + object_property_add_bool(obj, "pmu", arm_get_pmu, arm_set_pmu, > &error_abort); > } > > diff --git a/target/arm/kvm.c b/target/arm/kvm.c > index fe4f461d4ef6..69c961a4c62c 100644 > --- a/target/arm/kvm.c > +++ b/target/arm/kvm.c > @@ -162,6 +162,15 @@ void kvm_arm_set_cpu_features_from_host(ARMCPU *cpu) > env->features = arm_host_cpu_features.features; > } > > +bool kvm_arm_pmu_supported(CPUState *cpu) > +{ > + KVMState *s = KVM_STATE(current_machine->accelerator); > + int ret; > + > + ret = kvm_check_extension(s, KVM_CAP_ARM_PMU_V3); > + return ret > 0; return kvm_check_extension > +} > + > int kvm_arm_get_max_vm_ipa_size(MachineState *ms) > { > KVMState *s = KVM_STATE(ms->accelerator); > diff --git a/target/arm/kvm_arm.h b/target/arm/kvm_arm.h > index 812125f805a1..e0ded3607996 100644 > --- a/target/arm/kvm_arm.h > +++ b/target/arm/kvm_arm.h > @@ -216,6 +216,14 @@ void kvm_arm_set_cpu_features_from_host(ARMCPU *cpu); > */ > bool kvm_arm_aarch32_supported(CPUState *cs); > > +/** > + * bool kvm_arm_pmu_supported: > + * @cs: CPUState kernel-doc comment style? > + * > + * Returns true if the KVM VCPU can enable its PMU and false otherwise. > + */ > +bool kvm_arm_pmu_supported(CPUState *cs); > + > /** > * kvm_arm_get_max_vm_ipa_size - Returns the number of bits in the > * IPA address space supported by KVM > @@ -261,6 +269,11 @@ static inline bool kvm_arm_aarch32_supported(CPUState > *cs) > return false; > } > > +static inline bool kvm_arm_pmu_supported(CPUState *cs) > +{ > + return false; > +} > + > static inline int kvm_arm_get_max_vm_ipa_size(MachineState *ms) > { > return -ENOENT; > Reviewed-by: Eric Auger <eric.au...@redhat.com>
Thanks Eric