blob: 2454a1f2ca0c251532e93905f42d00fcdc1755aa [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* VMX-pmu related msrs test
*
* Copyright (C) 2021 Intel Corporation
*
* Test to check the effect of various CPUID settings
* on the MSR_IA32_PERF_CAPABILITIES MSR, and check that
* whatever we write with KVM_SET_MSR is _not_ modified
* in the guest and test it can be retrieved with KVM_GET_MSR.
*
* Test to check that invalid LBR formats are rejected.
*/
#define _GNU_SOURCE /* for program_invocation_short_name */
#include <sys/ioctl.h>
#include "kvm_util.h"
#include "vmx.h"
#define VCPU_ID 0
#define X86_FEATURE_PDCM (1<<15)
#define PMU_CAP_FW_WRITES (1ULL << 13)
#define PMU_CAP_LBR_FMT 0x3f
union cpuid10_eax {
struct {
unsigned int version_id:8;
unsigned int num_counters:8;
unsigned int bit_width:8;
unsigned int mask_length:8;
} split;
unsigned int full;
};
union perf_capabilities {
struct {
u64 lbr_format:6;
u64 pebs_trap:1;
u64 pebs_arch_reg:1;
u64 pebs_format:4;
u64 smm_freeze:1;
u64 full_width_write:1;
u64 pebs_baseline:1;
u64 perf_metrics:1;
u64 pebs_output_pt_available:1;
u64 anythread_deprecated:1;
};
u64 capabilities;
};
static void guest_code(void)
{
wrmsr(MSR_IA32_PERF_CAPABILITIES, PMU_CAP_LBR_FMT);
}
int main(int argc, char *argv[])
{
struct kvm_cpuid2 *cpuid;
struct kvm_cpuid_entry2 *entry_1_0;
struct kvm_cpuid_entry2 *entry_a_0;
bool pdcm_supported = false;
struct kvm_vm *vm;
int ret;
union cpuid10_eax eax;
union perf_capabilities host_cap;
host_cap.capabilities = kvm_get_feature_msr(MSR_IA32_PERF_CAPABILITIES);
host_cap.capabilities &= (PMU_CAP_FW_WRITES | PMU_CAP_LBR_FMT);
/* Create VM */
vm = vm_create_default(VCPU_ID, 0, guest_code);
cpuid = kvm_get_supported_cpuid();
if (kvm_get_cpuid_max_basic() >= 0xa) {
entry_1_0 = kvm_get_supported_cpuid_index(1, 0);
entry_a_0 = kvm_get_supported_cpuid_index(0xa, 0);
pdcm_supported = entry_1_0 && !!(entry_1_0->ecx & X86_FEATURE_PDCM);
eax.full = entry_a_0->eax;
}
if (!pdcm_supported) {
print_skip("MSR_IA32_PERF_CAPABILITIES is not supported by the vCPU");
exit(KSFT_SKIP);
}
if (!eax.split.version_id) {
print_skip("PMU is not supported by the vCPU");
exit(KSFT_SKIP);
}
/* testcase 1, set capabilities when we have PDCM bit */
vcpu_set_cpuid(vm, VCPU_ID, cpuid);
vcpu_set_msr(vm, 0, MSR_IA32_PERF_CAPABILITIES, PMU_CAP_FW_WRITES);
/* check capabilities can be retrieved with KVM_GET_MSR */
ASSERT_EQ(vcpu_get_msr(vm, VCPU_ID, MSR_IA32_PERF_CAPABILITIES), PMU_CAP_FW_WRITES);
/* check whatever we write with KVM_SET_MSR is _not_ modified */
vcpu_run(vm, VCPU_ID);
ASSERT_EQ(vcpu_get_msr(vm, VCPU_ID, MSR_IA32_PERF_CAPABILITIES), PMU_CAP_FW_WRITES);
/* testcase 2, check valid LBR formats are accepted */
vcpu_set_msr(vm, 0, MSR_IA32_PERF_CAPABILITIES, 0);
ASSERT_EQ(vcpu_get_msr(vm, VCPU_ID, MSR_IA32_PERF_CAPABILITIES), 0);
vcpu_set_msr(vm, 0, MSR_IA32_PERF_CAPABILITIES, host_cap.lbr_format);
ASSERT_EQ(vcpu_get_msr(vm, VCPU_ID, MSR_IA32_PERF_CAPABILITIES), (u64)host_cap.lbr_format);
/* testcase 3, check invalid LBR format is rejected */
ret = _vcpu_set_msr(vm, 0, MSR_IA32_PERF_CAPABILITIES, PMU_CAP_LBR_FMT);
TEST_ASSERT(ret == 0, "Bad PERF_CAPABILITIES didn't fail.");
kvm_vm_free(vm);
}