Commit de1b03f2 authored by Thomas Huth's avatar Thomas Huth Committed by Sean Christopherson
Browse files

KVM: selftests: x86: Use TAP interface in the vmx_pmu_caps test 



Use the kvm_test_harness.h interface in this test to get TAP
output, so that it is easier for the user to see what the test
is doing.

Signed-off-by: default avatarThomas Huth <thuth@redhat.com>
Link: https://lore.kernel.org/r/20240208204844.119326-8-thuth@redhat.com


[sean: make host_cap static]
Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
parent a6983e8f

tools/testing/selftests/kvm/x86_64/vmx_pmu_caps_test.c

+12 −40
Original line number Diff line number Diff line
@@ -15,10 +15,11 @@ 


#include <linux/bitmap.h>



#include "kvm_test_harness.h"

#include "kvm_util.h"

#include "vmx.h"



union perf_capabilities {

static union perf_capabilities {

	struct {

		u64	lbr_format:6;

		u64	pebs_trap:1;
@@ -32,7 +33,7 @@ union perf_capabilities { 
		u64	anythread_deprecated:1;

	};

	u64	capabilities;

};

} host_cap;



/*

 * The LBR format and most PEBS features are immutable, all other features are
@@ -73,19 +74,19 @@ static void guest_code(uint64_t current_val) 
	GUEST_DONE();

}



KVM_ONE_VCPU_TEST_SUITE(vmx_pmu_caps);



/*

 * Verify that guest WRMSRs to PERF_CAPABILITIES #GP regardless of the value

 * written, that the guest always sees the userspace controlled value, and that

 * PERF_CAPABILITIES is immutable after KVM_RUN.

 */

static void test_guest_wrmsr_perf_capabilities(union perf_capabilities host_cap)

KVM_ONE_VCPU_TEST(vmx_pmu_caps, guest_wrmsr_perf_capabilities, guest_code)

{

	struct kvm_vcpu *vcpu;

	struct kvm_vm *vm = vm_create_with_one_vcpu(&vcpu, guest_code);

	struct ucall uc;

	int r, i;



	vm_init_descriptor_tables(vm);

	vm_init_descriptor_tables(vcpu->vm);

	vcpu_init_descriptor_tables(vcpu);



	vcpu_set_msr(vcpu, MSR_IA32_PERF_CAPABILITIES, host_cap.capabilities);
@@ -117,31 +118,21 @@ static void test_guest_wrmsr_perf_capabilities(union perf_capabilities host_cap) 
		TEST_ASSERT(!r, "Post-KVM_RUN write '0x%llx'didn't fail",

			    host_cap.capabilities ^ BIT_ULL(i));

	}



	kvm_vm_free(vm);

}



/*

 * Verify KVM allows writing PERF_CAPABILITIES with all KVM-supported features

 * enabled, as well as '0' (to disable all features).

 */

static void test_basic_perf_capabilities(union perf_capabilities host_cap)

KVM_ONE_VCPU_TEST(vmx_pmu_caps, basic_perf_capabilities, guest_code)

{

	struct kvm_vcpu *vcpu;

	struct kvm_vm *vm = vm_create_with_one_vcpu(&vcpu, NULL);



	vcpu_set_msr(vcpu, MSR_IA32_PERF_CAPABILITIES, 0);

	vcpu_set_msr(vcpu, MSR_IA32_PERF_CAPABILITIES, host_cap.capabilities);



	kvm_vm_free(vm);

}



static void test_fungible_perf_capabilities(union perf_capabilities host_cap)

KVM_ONE_VCPU_TEST(vmx_pmu_caps, fungible_perf_capabilities, guest_code)

{

	const uint64_t fungible_caps = host_cap.capabilities & ~immutable_caps.capabilities;



	struct kvm_vcpu *vcpu;

	struct kvm_vm *vm = vm_create_with_one_vcpu(&vcpu, NULL);

	int bit;



	for_each_set_bit(bit, &fungible_caps, 64) {
@@ -150,8 +141,6 @@ static void test_fungible_perf_capabilities(union perf_capabilities host_cap) 
			     host_cap.capabilities & ~BIT_ULL(bit));

	}

	vcpu_set_msr(vcpu, MSR_IA32_PERF_CAPABILITIES, host_cap.capabilities);



	kvm_vm_free(vm);

}



/*
@@ -160,14 +149,11 @@ static void test_fungible_perf_capabilities(union perf_capabilities host_cap) 
 * separately as they are multi-bit values, e.g. toggling or setting a single

 * bit can generate a false positive without dedicated safeguards.

 */

static void test_immutable_perf_capabilities(union perf_capabilities host_cap)

KVM_ONE_VCPU_TEST(vmx_pmu_caps, immutable_perf_capabilities, guest_code)

{

	const uint64_t reserved_caps = (~host_cap.capabilities |

					immutable_caps.capabilities) &

				       ~format_caps.capabilities;



	struct kvm_vcpu *vcpu;

	struct kvm_vm *vm = vm_create_with_one_vcpu(&vcpu, NULL);

	union perf_capabilities val = host_cap;

	int r, bit;
@@ -201,8 +187,6 @@ static void test_immutable_perf_capabilities(union perf_capabilities host_cap) 
		TEST_ASSERT(!r, "Bad PEBS FMT = 0x%x didn't fail, host = 0x%x",

			    val.pebs_format, host_cap.pebs_format);

	}



	kvm_vm_free(vm);

}



/*
@@ -211,17 +195,13 @@ static void test_immutable_perf_capabilities(union perf_capabilities host_cap) 
 * LBR_TOS as those bits are writable across all uarch implementations (arch

 * LBRs will need to poke a different MSR).

 */

static void test_lbr_perf_capabilities(union perf_capabilities host_cap)

KVM_ONE_VCPU_TEST(vmx_pmu_caps, lbr_perf_capabilities, guest_code)

{

	struct kvm_vcpu *vcpu;

	struct kvm_vm *vm;

	int r;



	if (!host_cap.lbr_format)

		return;



	vm = vm_create_with_one_vcpu(&vcpu, NULL);



	vcpu_set_msr(vcpu, MSR_IA32_PERF_CAPABILITIES, host_cap.capabilities);

	vcpu_set_msr(vcpu, MSR_LBR_TOS, 7);
@@ -229,14 +209,10 @@ static void test_lbr_perf_capabilities(union perf_capabilities host_cap) 


	r = _vcpu_set_msr(vcpu, MSR_LBR_TOS, 7);

	TEST_ASSERT(!r, "Writing LBR_TOS should fail after disabling vPMU");



	kvm_vm_free(vm);

}



int main(int argc, char *argv[])

{

	union perf_capabilities host_cap;



	TEST_REQUIRE(get_kvm_param_bool("enable_pmu"));

	TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_PDCM));
@@ -248,9 +224,5 @@ int main(int argc, char *argv[]) 
	TEST_ASSERT(host_cap.full_width_write,

		    "Full-width writes should always be supported");



	test_basic_perf_capabilities(host_cap);

	test_fungible_perf_capabilities(host_cap);

	test_immutable_perf_capabilities(host_cap);

	test_guest_wrmsr_perf_capabilities(host_cap);

	test_lbr_perf_capabilities(host_cap);

	return test_harness_run(argc, argv);

}