diff --git a/hw/i386/x86.c b/hw/i386/x86.c index ed796fe6ba..d30cf27e29 100644 --- a/hw/i386/x86.c +++ b/hw/i386/x86.c @@ -1246,6 +1246,23 @@ static void x86_machine_set_oem_table_id(Object *obj, const char *value, strncpy(x86ms->oem_table_id, value, 8); } +static void x86_machine_get_bus_lock_ratelimit(Object *obj, Visitor *v, + const char *name, void *opaque, Error **errp) +{ + X86MachineState *x86ms = X86_MACHINE(obj); + uint64_t bus_lock_ratelimit = x86ms->bus_lock_ratelimit; + + visit_type_uint64(v, name, &bus_lock_ratelimit, errp); +} + +static void x86_machine_set_bus_lock_ratelimit(Object *obj, Visitor *v, + const char *name, void *opaque, Error **errp) +{ + X86MachineState *x86ms = X86_MACHINE(obj); + + visit_type_uint64(v, name, &x86ms->bus_lock_ratelimit, errp); +} + static void x86_machine_initfn(Object *obj) { X86MachineState *x86ms = X86_MACHINE(obj); @@ -1256,6 +1273,7 @@ static void x86_machine_initfn(Object *obj) x86ms->pci_irq_mask = ACPI_BUILD_PCI_IRQS; x86ms->oem_id = g_strndup(ACPI_BUILD_APPNAME6, 6); x86ms->oem_table_id = g_strndup(ACPI_BUILD_APPNAME8, 8); + x86ms->bus_lock_ratelimit = 0; } static void x86_machine_class_init(ObjectClass *oc, void *data) @@ -1299,6 +1317,12 @@ static void x86_machine_class_init(ObjectClass *oc, void *data) "Override the default value of field OEM Table ID " "in ACPI table header." "The string may be up to 8 bytes in size"); + + object_class_property_add(oc, X86_MACHINE_BUS_LOCK_RATELIMIT, "uint64_t", + x86_machine_get_bus_lock_ratelimit, + x86_machine_set_bus_lock_ratelimit, NULL, NULL); + object_class_property_set_description(oc, X86_MACHINE_BUS_LOCK_RATELIMIT, + "Set the ratelimit for the bus locks acquired in VMs"); } static const TypeInfo x86_machine_info = { diff --git a/include/hw/i386/x86.h b/include/hw/i386/x86.h index c09b648dff..25a1f16f01 100644 --- a/include/hw/i386/x86.h +++ b/include/hw/i386/x86.h @@ -74,12 +74,20 @@ struct X86MachineState { * will be translated to MSI messages in the address space. */ AddressSpace *ioapic_as; + + /* + * Ratelimit enforced on detected bus locks in guest. + * The default value of the bus_lock_ratelimit is 0 per second, + * which means no limitation on the guest's bus locks. + */ + uint64_t bus_lock_ratelimit; }; #define X86_MACHINE_SMM "smm" #define X86_MACHINE_ACPI "acpi" #define X86_MACHINE_OEM_ID "x-oem-id" #define X86_MACHINE_OEM_TABLE_ID "x-oem-table-id" +#define X86_MACHINE_BUS_LOCK_RATELIMIT "bus-lock-ratelimit" #define TYPE_X86_MACHINE MACHINE_TYPE_NAME("x86") OBJECT_DECLARE_TYPE(X86MachineState, X86MachineClass, X86_MACHINE) diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c index c676ee8b38..ad950c3c27 100644 --- a/target/i386/kvm/kvm.c +++ b/target/i386/kvm/kvm.c @@ -132,6 +132,9 @@ static struct kvm_cpuid2 *cpuid_cache; static struct kvm_cpuid2 *hv_cpuid_cache; static struct kvm_msr_list *kvm_feature_msrs; +#define BUS_LOCK_SLICE_TIME 1000000000ULL /* ns */ +static RateLimit bus_lock_ratelimit_ctrl; + int kvm_has_pit_state2(void) { return has_pit_state2; @@ -2312,6 +2315,28 @@ int kvm_arch_init(MachineState *ms, KVMState *s) } } + if (object_dynamic_cast(OBJECT(ms), TYPE_X86_MACHINE)) { + X86MachineState *x86ms = X86_MACHINE(ms); + + if (x86ms->bus_lock_ratelimit > 0) { + ret = kvm_check_extension(s, KVM_CAP_X86_BUS_LOCK_EXIT); + if (!(ret & KVM_BUS_LOCK_DETECTION_EXIT)) { + error_report("kvm: bus lock detection unsupported"); + return -ENOTSUP; + } + ret = kvm_vm_enable_cap(s, KVM_CAP_X86_BUS_LOCK_EXIT, 0, + KVM_BUS_LOCK_DETECTION_EXIT); + if (ret < 0) { + error_report("kvm: Failed to enable bus lock detection cap: %s", + strerror(-ret)); + return ret; + } + ratelimit_init(&bus_lock_ratelimit_ctrl); + ratelimit_set_speed(&bus_lock_ratelimit_ctrl, + x86ms->bus_lock_ratelimit, BUS_LOCK_SLICE_TIME); + } + } + return 0; } @@ -4266,6 +4291,15 @@ void kvm_arch_pre_run(CPUState *cpu, struct kvm_run *run) } } +static void kvm_rate_limit_on_bus_lock(void) +{ + uint64_t delay_ns = ratelimit_calculate_delay(&bus_lock_ratelimit_ctrl, 1); + + if (delay_ns) { + g_usleep(delay_ns / SCALE_US); + } +} + MemTxAttrs kvm_arch_post_run(CPUState *cpu, struct kvm_run *run) { X86CPU *x86_cpu = X86_CPU(cpu); @@ -4281,6 +4315,9 @@ MemTxAttrs kvm_arch_post_run(CPUState *cpu, struct kvm_run *run) } else { env->eflags &= ~IF_MASK; } + if (run->flags & KVM_RUN_X86_BUS_LOCK) { + kvm_rate_limit_on_bus_lock(); + } /* We need to protect the apic state against concurrent accesses from * different threads in case the userspace irqchip is used. */ @@ -4639,6 +4676,10 @@ int kvm_arch_handle_exit(CPUState *cs, struct kvm_run *run) ioapic_eoi_broadcast(run->eoi.vector); ret = 0; break; + case KVM_EXIT_X86_BUS_LOCK: + /* already handled in kvm_arch_post_run */ + ret = 0; + break; default: fprintf(stderr, "KVM: unknown exit reason %d\n", run->exit_reason); ret = -1;