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-rw-r--r--Documentation/virt/kvm/devices/vcpu.rst34
-rw-r--r--arch/arm64/include/asm/kvm_host.h15
-rw-r--r--arch/arm64/include/uapi/asm/kvm.h4
-rw-r--r--arch/arm64/kvm/arm.c21
-rw-r--r--arch/arm64/kvm/pmu-emul.c141
-rw-r--r--include/kvm/arm_pmu.h5
-rw-r--r--include/linux/perf_event.h2
-rw-r--r--tools/arch/arm64/include/uapi/asm/kvm.h1
8 files changed, 189 insertions, 34 deletions
diff --git a/Documentation/virt/kvm/devices/vcpu.rst b/Documentation/virt/kvm/devices/vcpu.rst
index 60a29972d3f1..260db203a1e2 100644
--- a/Documentation/virt/kvm/devices/vcpu.rst
+++ b/Documentation/virt/kvm/devices/vcpu.rst
@@ -70,7 +70,7 @@ irqchip.
-ENODEV PMUv3 not supported or GIC not initialized
-ENXIO PMUv3 not properly configured or in-kernel irqchip not
configured as required prior to calling this attribute
- -EBUSY PMUv3 already initialized
+ -EBUSY PMUv3 already initialized or a VCPU has already run
-EINVAL Invalid filter range
======= ======================================================
@@ -104,6 +104,38 @@ hardware event. Filtering event 0x1E (CHAIN) has no effect either, as it
isn't strictly speaking an event. Filtering the cycle counter is possible
using event 0x11 (CPU_CYCLES).
+1.4 ATTRIBUTE: KVM_ARM_VCPU_PMU_V3_SET_PMU
+------------------------------------------
+
+:Parameters: in kvm_device_attr.addr the address to an int representing the PMU
+ identifier.
+
+:Returns:
+
+ ======= ====================================================
+ -EBUSY PMUv3 already initialized, a VCPU has already run or
+ an event filter has already been set
+ -EFAULT Error accessing the PMU identifier
+ -ENXIO PMU not found
+ -ENODEV PMUv3 not supported or GIC not initialized
+ -ENOMEM Could not allocate memory
+ ======= ====================================================
+
+Request that the VCPU uses the specified hardware PMU when creating guest events
+for the purpose of PMU emulation. The PMU identifier can be read from the "type"
+file for the desired PMU instance under /sys/devices (or, equivalent,
+/sys/bus/even_source). This attribute is particularly useful on heterogeneous
+systems where there are at least two CPU PMUs on the system. The PMU that is set
+for one VCPU will be used by all the other VCPUs. It isn't possible to set a PMU
+if a PMU event filter is already present.
+
+Note that KVM will not make any attempts to run the VCPU on the physical CPUs
+associated with the PMU specified by this attribute. This is entirely left to
+userspace. However, attempting to run the VCPU on a physical CPU not supported
+by the PMU will fail and KVM_RUN will return with
+exit_reason = KVM_EXIT_FAIL_ENTRY and populate the fail_entry struct by setting
+hardare_entry_failure_reason field to KVM_EXIT_FAIL_ENTRY_CPU_UNSUPPORTED and
+the cpu field to the processor id.
2. GROUP: KVM_ARM_VCPU_TIMER_CTRL
=================================
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 72e8c983130c..76f795b628f1 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -129,13 +129,16 @@ struct kvm_arch {
* up to 2^10 events (ARMv8.0) or 2^16 events (ARMv8.1+).
*/
unsigned long *pmu_filter;
- unsigned int pmuver;
+ struct arm_pmu *arm_pmu;
+
+ cpumask_var_t supported_cpus;
u8 pfr0_csv2;
u8 pfr0_csv3;
/* Memory Tagging Extension enabled for the guest */
bool mte_enabled;
+ bool ran_once;
};
struct kvm_vcpu_fault_info {
@@ -436,6 +439,7 @@ struct kvm_vcpu_arch {
#define KVM_ARM64_DEBUG_STATE_SAVE_SPE (1 << 12) /* Save SPE context if active */
#define KVM_ARM64_DEBUG_STATE_SAVE_TRBE (1 << 13) /* Save TRBE context if active */
#define KVM_ARM64_FP_FOREIGN_FPSTATE (1 << 14)
+#define KVM_ARM64_ON_UNSUPPORTED_CPU (1 << 15) /* Physical CPU not in supported_cpus */
#define KVM_GUESTDBG_VALID_MASK (KVM_GUESTDBG_ENABLE | \
KVM_GUESTDBG_USE_SW_BP | \
@@ -454,6 +458,15 @@ struct kvm_vcpu_arch {
#define vcpu_has_ptrauth(vcpu) false
#endif
+#define vcpu_on_unsupported_cpu(vcpu) \
+ ((vcpu)->arch.flags & KVM_ARM64_ON_UNSUPPORTED_CPU)
+
+#define vcpu_set_on_unsupported_cpu(vcpu) \
+ ((vcpu)->arch.flags |= KVM_ARM64_ON_UNSUPPORTED_CPU)
+
+#define vcpu_clear_on_unsupported_cpu(vcpu) \
+ ((vcpu)->arch.flags &= ~KVM_ARM64_ON_UNSUPPORTED_CPU)
+
#define vcpu_gp_regs(v) (&(v)->arch.ctxt.regs)
/*
diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h
index b3edde68bc3e..d49f714f48e6 100644
--- a/arch/arm64/include/uapi/asm/kvm.h
+++ b/arch/arm64/include/uapi/asm/kvm.h
@@ -362,6 +362,7 @@ struct kvm_arm_copy_mte_tags {
#define KVM_ARM_VCPU_PMU_V3_IRQ 0
#define KVM_ARM_VCPU_PMU_V3_INIT 1
#define KVM_ARM_VCPU_PMU_V3_FILTER 2
+#define KVM_ARM_VCPU_PMU_V3_SET_PMU 3
#define KVM_ARM_VCPU_TIMER_CTRL 1
#define KVM_ARM_VCPU_TIMER_IRQ_VTIMER 0
#define KVM_ARM_VCPU_TIMER_IRQ_PTIMER 1
@@ -413,6 +414,9 @@ struct kvm_arm_copy_mte_tags {
#define KVM_PSCI_RET_INVAL PSCI_RET_INVALID_PARAMS
#define KVM_PSCI_RET_DENIED PSCI_RET_DENIED
+/* run->fail_entry.hardware_entry_failure_reason codes. */
+#define KVM_EXIT_FAIL_ENTRY_CPU_UNSUPPORTED (1ULL << 0)
+
#endif
#endif /* __ARM_KVM_H__ */
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 418014998f18..fefd5774ab55 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -145,6 +145,10 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
if (ret)
goto out_free_stage2_pgd;
+ if (!zalloc_cpumask_var(&kvm->arch.supported_cpus, GFP_KERNEL))
+ goto out_free_stage2_pgd;
+ cpumask_copy(kvm->arch.supported_cpus, cpu_possible_mask);
+
kvm_vgic_early_init(kvm);
/* The maximum number of VCPUs is limited by the host's GIC model */
@@ -171,6 +175,7 @@ vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
void kvm_arch_destroy_vm(struct kvm *kvm)
{
bitmap_free(kvm->arch.pmu_filter);
+ free_cpumask_var(kvm->arch.supported_cpus);
kvm_vgic_destroy(kvm);
@@ -406,6 +411,9 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
if (vcpu_has_ptrauth(vcpu))
vcpu_ptrauth_disable(vcpu);
kvm_arch_vcpu_load_debug_state_flags(vcpu);
+
+ if (!cpumask_test_cpu(smp_processor_id(), vcpu->kvm->arch.supported_cpus))
+ vcpu_set_on_unsupported_cpu(vcpu);
}
void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
@@ -419,6 +427,7 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
kvm_vcpu_pmu_restore_host(vcpu);
kvm_arm_vmid_clear_active();
+ vcpu_clear_on_unsupported_cpu(vcpu);
vcpu->cpu = -1;
}
@@ -549,6 +558,10 @@ int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu)
if (kvm_vm_is_protected(kvm))
kvm_call_hyp_nvhe(__pkvm_vcpu_init_traps, vcpu);
+ mutex_lock(&kvm->lock);
+ kvm->arch.ran_once = true;
+ mutex_unlock(&kvm->lock);
+
return ret;
}
@@ -707,6 +720,14 @@ static bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu, int *ret)
}
}
+ if (unlikely(vcpu_on_unsupported_cpu(vcpu))) {
+ run->exit_reason = KVM_EXIT_FAIL_ENTRY;
+ run->fail_entry.hardware_entry_failure_reason = KVM_EXIT_FAIL_ENTRY_CPU_UNSUPPORTED;
+ run->fail_entry.cpu = smp_processor_id();
+ *ret = 0;
+ return true;
+ }
+
return kvm_request_pending(vcpu) ||
xfer_to_guest_mode_work_pending();
}
diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c
index fbcfd4ec6f92..4526a5824dac 100644
--- a/arch/arm64/kvm/pmu-emul.c
+++ b/arch/arm64/kvm/pmu-emul.c
@@ -7,6 +7,7 @@
#include <linux/cpu.h>
#include <linux/kvm.h>
#include <linux/kvm_host.h>
+#include <linux/list.h>
#include <linux/perf_event.h>
#include <linux/perf/arm_pmu.h>
#include <linux/uaccess.h>
@@ -16,6 +17,9 @@
DEFINE_STATIC_KEY_FALSE(kvm_arm_pmu_available);
+static LIST_HEAD(arm_pmus);
+static DEFINE_MUTEX(arm_pmus_lock);
+
static void kvm_pmu_create_perf_event(struct kvm_vcpu *vcpu, u64 select_idx);
static void kvm_pmu_update_pmc_chained(struct kvm_vcpu *vcpu, u64 select_idx);
static void kvm_pmu_stop_counter(struct kvm_vcpu *vcpu, struct kvm_pmc *pmc);
@@ -24,7 +28,11 @@ static void kvm_pmu_stop_counter(struct kvm_vcpu *vcpu, struct kvm_pmc *pmc);
static u32 kvm_pmu_event_mask(struct kvm *kvm)
{
- switch (kvm->arch.pmuver) {
+ unsigned int pmuver;
+
+ pmuver = kvm->arch.arm_pmu->pmuver;
+
+ switch (pmuver) {
case ID_AA64DFR0_PMUVER_8_0:
return GENMASK(9, 0);
case ID_AA64DFR0_PMUVER_8_1:
@@ -33,7 +41,7 @@ static u32 kvm_pmu_event_mask(struct kvm *kvm)
case ID_AA64DFR0_PMUVER_8_7:
return GENMASK(15, 0);
default: /* Shouldn't be here, just for sanity */
- WARN_ONCE(1, "Unknown PMU version %d\n", kvm->arch.pmuver);
+ WARN_ONCE(1, "Unknown PMU version %d\n", pmuver);
return 0;
}
}
@@ -600,6 +608,7 @@ static bool kvm_pmu_counter_is_enabled(struct kvm_vcpu *vcpu, u64 select_idx)
*/
static void kvm_pmu_create_perf_event(struct kvm_vcpu *vcpu, u64 select_idx)
{
+ struct arm_pmu *arm_pmu = vcpu->kvm->arch.arm_pmu;
struct kvm_pmu *pmu = &vcpu->arch.pmu;
struct kvm_pmc *pmc;
struct perf_event *event;
@@ -636,7 +645,7 @@ static void kvm_pmu_create_perf_event(struct kvm_vcpu *vcpu, u64 select_idx)
return;
memset(&attr, 0, sizeof(struct perf_event_attr));
- attr.type = PERF_TYPE_RAW;
+ attr.type = arm_pmu->pmu.type;
attr.size = sizeof(attr);
attr.pinned = 1;
attr.disabled = !kvm_pmu_counter_is_enabled(vcpu, pmc->idx);
@@ -745,17 +754,33 @@ void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data,
void kvm_host_pmu_init(struct arm_pmu *pmu)
{
- if (pmu->pmuver != 0 && pmu->pmuver != ID_AA64DFR0_PMUVER_IMP_DEF &&
- !kvm_arm_support_pmu_v3() && !is_protected_kvm_enabled())
+ struct arm_pmu_entry *entry;
+
+ if (pmu->pmuver == 0 || pmu->pmuver == ID_AA64DFR0_PMUVER_IMP_DEF ||
+ is_protected_kvm_enabled())
+ return;
+
+ mutex_lock(&arm_pmus_lock);
+
+ entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry)
+ goto out_unlock;
+
+ entry->arm_pmu = pmu;
+ list_add_tail(&entry->entry, &arm_pmus);
+
+ if (list_is_singular(&arm_pmus))
static_branch_enable(&kvm_arm_pmu_available);
+
+out_unlock:
+ mutex_unlock(&arm_pmus_lock);
}
-static int kvm_pmu_probe_pmuver(void)
+static struct arm_pmu *kvm_pmu_probe_armpmu(void)
{
struct perf_event_attr attr = { };
struct perf_event *event;
- struct arm_pmu *pmu;
- int pmuver = ID_AA64DFR0_PMUVER_IMP_DEF;
+ struct arm_pmu *pmu = NULL;
/*
* Create a dummy event that only counts user cycles. As we'll never
@@ -780,19 +805,20 @@ static int kvm_pmu_probe_pmuver(void)
if (IS_ERR(event)) {
pr_err_once("kvm: pmu event creation failed %ld\n",
PTR_ERR(event));
- return ID_AA64DFR0_PMUVER_IMP_DEF;
+ return NULL;
}
if (event->pmu) {
pmu = to_arm_pmu(event->pmu);
- if (pmu->pmuver)
- pmuver = pmu->pmuver;
+ if (pmu->pmuver == 0 ||
+ pmu->pmuver == ID_AA64DFR0_PMUVER_IMP_DEF)
+ pmu = NULL;
}
perf_event_disable(event);
perf_event_release_kernel(event);
- return pmuver;
+ return pmu;
}
u64 kvm_pmu_get_pmceid(struct kvm_vcpu *vcpu, bool pmceid1)
@@ -810,7 +836,7 @@ u64 kvm_pmu_get_pmceid(struct kvm_vcpu *vcpu, bool pmceid1)
* Don't advertise STALL_SLOT, as PMMIR_EL0 is handled
* as RAZ
*/
- if (vcpu->kvm->arch.pmuver >= ID_AA64DFR0_PMUVER_8_4)
+ if (vcpu->kvm->arch.arm_pmu->pmuver >= ID_AA64DFR0_PMUVER_8_4)
val &= ~BIT_ULL(ARMV8_PMUV3_PERFCTR_STALL_SLOT - 32);
base = 32;
}
@@ -922,26 +948,64 @@ static bool pmu_irq_is_valid(struct kvm *kvm, int irq)
return true;
}
+static int kvm_arm_pmu_v3_set_pmu(struct kvm_vcpu *vcpu, int pmu_id)
+{
+ struct kvm *kvm = vcpu->kvm;
+ struct arm_pmu_entry *entry;
+ struct arm_pmu *arm_pmu;
+ int ret = -ENXIO;
+
+ mutex_lock(&kvm->lock);
+ mutex_lock(&arm_pmus_lock);
+
+ list_for_each_entry(entry, &arm_pmus, entry) {
+ arm_pmu = entry->arm_pmu;
+ if (arm_pmu->pmu.type == pmu_id) {
+ if (kvm->arch.ran_once ||
+ (kvm->arch.pmu_filter && kvm->arch.arm_pmu != arm_pmu)) {
+ ret = -EBUSY;
+ break;
+ }
+
+ kvm->arch.arm_pmu = arm_pmu;
+ cpumask_copy(kvm->arch.supported_cpus, &arm_pmu->supported_cpus);
+ ret = 0;
+ break;
+ }
+ }
+
+ mutex_unlock(&arm_pmus_lock);
+ mutex_unlock(&kvm->lock);
+ return ret;
+}
+
int kvm_arm_pmu_v3_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
{
+ struct kvm *kvm = vcpu->kvm;
+
if (!kvm_vcpu_has_pmu(vcpu))
return -ENODEV;
if (vcpu->arch.pmu.created)
return -EBUSY;
- if (!vcpu->kvm->arch.pmuver)
- vcpu->kvm->arch.pmuver = kvm_pmu_probe_pmuver();
-
- if (vcpu->kvm->arch.pmuver == ID_AA64DFR0_PMUVER_IMP_DEF)
- return -ENODEV;
+ mutex_lock(&kvm->lock);
+ if (!kvm->arch.arm_pmu) {
+ /* No PMU set, get the default one */
+ kvm->arch.arm_pmu = kvm_pmu_probe_armpmu();
+ if (!kvm->arch.arm_pmu) {
+ mutex_unlock(&kvm->lock);
+ return -ENODEV;
+ }
+ }
+ mutex_unlock(&kvm->lock);
switch (attr->attr) {
case KVM_ARM_VCPU_PMU_V3_IRQ: {
int __user *uaddr = (int __user *)(long)attr->addr;
int irq;
- if (!irqchip_in_kernel(vcpu->kvm))
+ if (!irqchip_in_kernel(kvm))
return -EINVAL;
if (get_user(irq, uaddr))
@@ -951,7 +1015,7 @@ int kvm_arm_pmu_v3_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
if (!(irq_is_ppi(irq) || irq_is_spi(irq)))
return -EINVAL;
- if (!pmu_irq_is_valid(vcpu->kvm, irq))
+ if (!pmu_irq_is_valid(kvm, irq))
return -EINVAL;
if (kvm_arm_pmu_irq_initialized(vcpu))
@@ -966,7 +1030,7 @@ int kvm_arm_pmu_v3_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
struct kvm_pmu_event_filter filter;
int nr_events;
- nr_events = kvm_pmu_event_mask(vcpu->kvm) + 1;
+ nr_events = kvm_pmu_event_mask(kvm) + 1;
uaddr = (struct kvm_pmu_event_filter __user *)(long)attr->addr;
@@ -978,12 +1042,17 @@ int kvm_arm_pmu_v3_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
filter.action != KVM_PMU_EVENT_DENY))
return -EINVAL;
- mutex_lock(&vcpu->kvm->lock);
+ mutex_lock(&kvm->lock);
- if (!vcpu->kvm->arch.pmu_filter) {
- vcpu->kvm->arch.pmu_filter = bitmap_alloc(nr_events, GFP_KERNEL_ACCOUNT);
- if (!vcpu->kvm->arch.pmu_filter) {
- mutex_unlock(&vcpu->kvm->lock);
+ if (kvm->arch.ran_once) {
+ mutex_unlock(&kvm->lock);
+ return -EBUSY;
+ }
+
+ if (!kvm->arch.pmu_filter) {
+ kvm->arch.pmu_filter = bitmap_alloc(nr_events, GFP_KERNEL_ACCOUNT);
+ if (!kvm->arch.pmu_filter) {
+ mutex_unlock(&kvm->lock);
return -ENOMEM;
}
@@ -994,20 +1063,29 @@ int kvm_arm_pmu_v3_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
* events, the default is to allow.
*/
if (filter.action == KVM_PMU_EVENT_ALLOW)
- bitmap_zero(vcpu->kvm->arch.pmu_filter, nr_events);
+ bitmap_zero(kvm->arch.pmu_filter, nr_events);
else
- bitmap_fill(vcpu->kvm->arch.pmu_filter, nr_events);
+ bitmap_fill(kvm->arch.pmu_filter, nr_events);
}
if (filter.action == KVM_PMU_EVENT_ALLOW)
- bitmap_set(vcpu->kvm->arch.pmu_filter, filter.base_event, filter.nevents);
+ bitmap_set(kvm->arch.pmu_filter, filter.base_event, filter.nevents);
else
- bitmap_clear(vcpu->kvm->arch.pmu_filter, filter.base_event, filter.nevents);
+ bitmap_clear(kvm->arch.pmu_filter, filter.base_event, filter.nevents);
- mutex_unlock(&vcpu->kvm->lock);
+ mutex_unlock(&kvm->lock);
return 0;
}
+ case KVM_ARM_VCPU_PMU_V3_SET_PMU: {
+ int __user *uaddr = (int __user *)(long)attr->addr;
+ int pmu_id;
+
+ if (get_user(pmu_id, uaddr))
+ return -EFAULT;
+
+ return kvm_arm_pmu_v3_set_pmu(vcpu, pmu_id);
+ }
case KVM_ARM_VCPU_PMU_V3_INIT:
return kvm_arm_pmu_v3_init(vcpu);
}
@@ -1045,6 +1123,7 @@ int kvm_arm_pmu_v3_has_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
case KVM_ARM_VCPU_PMU_V3_IRQ:
case KVM_ARM_VCPU_PMU_V3_INIT:
case KVM_ARM_VCPU_PMU_V3_FILTER:
+ case KVM_ARM_VCPU_PMU_V3_SET_PMU:
if (kvm_vcpu_has_pmu(vcpu))
return 0;
}
diff --git a/include/kvm/arm_pmu.h b/include/kvm/arm_pmu.h
index f9ed4c171d7b..20193416d214 100644
--- a/include/kvm/arm_pmu.h
+++ b/include/kvm/arm_pmu.h
@@ -29,6 +29,11 @@ struct kvm_pmu {
struct irq_work overflow_work;
};
+struct arm_pmu_entry {
+ struct list_head entry;
+ struct arm_pmu *arm_pmu;
+};
+
DECLARE_STATIC_KEY_FALSE(kvm_arm_pmu_available);
static __always_inline bool kvm_arm_support_pmu_v3(void)
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 733649184b27..af97dd427501 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -864,7 +864,7 @@ struct perf_event_context {
#define PERF_NR_CONTEXTS 4
/**
- * struct perf_event_cpu_context - per cpu event context structure
+ * struct perf_cpu_context - per cpu event context structure
*/
struct perf_cpu_context {
struct perf_event_context ctx;
diff --git a/tools/arch/arm64/include/uapi/asm/kvm.h b/tools/arch/arm64/include/uapi/asm/kvm.h
index b3edde68bc3e..1d0a0a2a9711 100644
--- a/tools/arch/arm64/include/uapi/asm/kvm.h
+++ b/tools/arch/arm64/include/uapi/asm/kvm.h
@@ -362,6 +362,7 @@ struct kvm_arm_copy_mte_tags {
#define KVM_ARM_VCPU_PMU_V3_IRQ 0
#define KVM_ARM_VCPU_PMU_V3_INIT 1
#define KVM_ARM_VCPU_PMU_V3_FILTER 2
+#define KVM_ARM_VCPU_PMU_V3_SET_PMU 3
#define KVM_ARM_VCPU_TIMER_CTRL 1
#define KVM_ARM_VCPU_TIMER_IRQ_VTIMER 0
#define KVM_ARM_VCPU_TIMER_IRQ_PTIMER 1
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.