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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * vpmu_counter_access - Test vPMU event counter access4 *5 * Copyright (c) 2023 Google LLC.6 *7 * This test checks if the guest can see the same number of the PMU event8 * counters (PMCR_EL0.N) that userspace sets, if the guest can access9 * those counters, and if the guest is prevented from accessing any10 * other counters.11 * It also checks if the userspace accesses to the PMU regsisters honor the12 * PMCR.N value that's set for the guest.13 * This test runs only when KVM_CAP_ARM_PMU_V3 is supported on the host.14 */15#include <kvm_util.h>16#include <processor.h>17#include <test_util.h>18#include <vgic.h>19#include <perf/arm_pmuv3.h>20#include <linux/bitfield.h>21 22/* The max number of the PMU event counters (excluding the cycle counter) */23#define ARMV8_PMU_MAX_GENERAL_COUNTERS	(ARMV8_PMU_MAX_COUNTERS - 1)24 25/* The cycle counter bit position that's common among the PMU registers */26#define ARMV8_PMU_CYCLE_IDX		3127 28struct vpmu_vm {29	struct kvm_vm *vm;30	struct kvm_vcpu *vcpu;31	int gic_fd;32};33 34static struct vpmu_vm vpmu_vm;35 36struct pmreg_sets {37	uint64_t set_reg_id;38	uint64_t clr_reg_id;39};40 41#define PMREG_SET(set, clr) {.set_reg_id = set, .clr_reg_id = clr}42 43static uint64_t get_pmcr_n(uint64_t pmcr)44{45	return FIELD_GET(ARMV8_PMU_PMCR_N, pmcr);46}47 48static void set_pmcr_n(uint64_t *pmcr, uint64_t pmcr_n)49{50	u64p_replace_bits((__u64 *) pmcr, pmcr_n, ARMV8_PMU_PMCR_N);51}52 53static uint64_t get_counters_mask(uint64_t n)54{55	uint64_t mask = BIT(ARMV8_PMU_CYCLE_IDX);56 57	if (n)58		mask |= GENMASK(n - 1, 0);59	return mask;60}61 62/* Read PMEVTCNTR<n>_EL0 through PMXEVCNTR_EL0 */63static inline unsigned long read_sel_evcntr(int sel)64{65	write_sysreg(sel, pmselr_el0);66	isb();67	return read_sysreg(pmxevcntr_el0);68}69 70/* Write PMEVTCNTR<n>_EL0 through PMXEVCNTR_EL0 */71static inline void write_sel_evcntr(int sel, unsigned long val)72{73	write_sysreg(sel, pmselr_el0);74	isb();75	write_sysreg(val, pmxevcntr_el0);76	isb();77}78 79/* Read PMEVTYPER<n>_EL0 through PMXEVTYPER_EL0 */80static inline unsigned long read_sel_evtyper(int sel)81{82	write_sysreg(sel, pmselr_el0);83	isb();84	return read_sysreg(pmxevtyper_el0);85}86 87/* Write PMEVTYPER<n>_EL0 through PMXEVTYPER_EL0 */88static inline void write_sel_evtyper(int sel, unsigned long val)89{90	write_sysreg(sel, pmselr_el0);91	isb();92	write_sysreg(val, pmxevtyper_el0);93	isb();94}95 96static void pmu_disable_reset(void)97{98	uint64_t pmcr = read_sysreg(pmcr_el0);99 100	/* Reset all counters, disabling them */101	pmcr &= ~ARMV8_PMU_PMCR_E;102	write_sysreg(pmcr | ARMV8_PMU_PMCR_P, pmcr_el0);103	isb();104}105 106#define RETURN_READ_PMEVCNTRN(n) \107	return read_sysreg(pmevcntr##n##_el0)108static unsigned long read_pmevcntrn(int n)109{110	PMEVN_SWITCH(n, RETURN_READ_PMEVCNTRN);111	return 0;112}113 114#define WRITE_PMEVCNTRN(n) \115	write_sysreg(val, pmevcntr##n##_el0)116static void write_pmevcntrn(int n, unsigned long val)117{118	PMEVN_SWITCH(n, WRITE_PMEVCNTRN);119	isb();120}121 122#define READ_PMEVTYPERN(n) \123	return read_sysreg(pmevtyper##n##_el0)124static unsigned long read_pmevtypern(int n)125{126	PMEVN_SWITCH(n, READ_PMEVTYPERN);127	return 0;128}129 130#define WRITE_PMEVTYPERN(n) \131	write_sysreg(val, pmevtyper##n##_el0)132static void write_pmevtypern(int n, unsigned long val)133{134	PMEVN_SWITCH(n, WRITE_PMEVTYPERN);135	isb();136}137 138/*139 * The pmc_accessor structure has pointers to PMEV{CNTR,TYPER}<n>_EL0140 * accessors that test cases will use. Each of the accessors will141 * either directly reads/writes PMEV{CNTR,TYPER}<n>_EL0142 * (i.e. {read,write}_pmev{cnt,type}rn()), or reads/writes them through143 * PMXEV{CNTR,TYPER}_EL0 (i.e. {read,write}_sel_ev{cnt,type}r()).144 *145 * This is used to test that combinations of those accessors provide146 * the consistent behavior.147 */148struct pmc_accessor {149	/* A function to be used to read PMEVTCNTR<n>_EL0 */150	unsigned long	(*read_cntr)(int idx);151	/* A function to be used to write PMEVTCNTR<n>_EL0 */152	void		(*write_cntr)(int idx, unsigned long val);153	/* A function to be used to read PMEVTYPER<n>_EL0 */154	unsigned long	(*read_typer)(int idx);155	/* A function to be used to write PMEVTYPER<n>_EL0 */156	void		(*write_typer)(int idx, unsigned long val);157};158 159struct pmc_accessor pmc_accessors[] = {160	/* test with all direct accesses */161	{ read_pmevcntrn, write_pmevcntrn, read_pmevtypern, write_pmevtypern },162	/* test with all indirect accesses */163	{ read_sel_evcntr, write_sel_evcntr, read_sel_evtyper, write_sel_evtyper },164	/* read with direct accesses, and write with indirect accesses */165	{ read_pmevcntrn, write_sel_evcntr, read_pmevtypern, write_sel_evtyper },166	/* read with indirect accesses, and write with direct accesses */167	{ read_sel_evcntr, write_pmevcntrn, read_sel_evtyper, write_pmevtypern },168};169 170/*171 * Convert a pointer of pmc_accessor to an index in pmc_accessors[],172 * assuming that the pointer is one of the entries in pmc_accessors[].173 */174#define PMC_ACC_TO_IDX(acc)	(acc - &pmc_accessors[0])175 176#define GUEST_ASSERT_BITMAP_REG(regname, mask, set_expected)			 \177{										 \178	uint64_t _tval = read_sysreg(regname);					 \179										 \180	if (set_expected)							 \181		__GUEST_ASSERT((_tval & mask),					 \182				"tval: 0x%lx; mask: 0x%lx; set_expected: %u",	 \183				_tval, mask, set_expected);			 \184	else									 \185		__GUEST_ASSERT(!(_tval & mask),					 \186				"tval: 0x%lx; mask: 0x%lx; set_expected: %u",	 \187				_tval, mask, set_expected);			 \188}189 190/*191 * Check if @mask bits in {PMCNTEN,PMINTEN,PMOVS}{SET,CLR} registers192 * are set or cleared as specified in @set_expected.193 */194static void check_bitmap_pmu_regs(uint64_t mask, bool set_expected)195{196	GUEST_ASSERT_BITMAP_REG(pmcntenset_el0, mask, set_expected);197	GUEST_ASSERT_BITMAP_REG(pmcntenclr_el0, mask, set_expected);198	GUEST_ASSERT_BITMAP_REG(pmintenset_el1, mask, set_expected);199	GUEST_ASSERT_BITMAP_REG(pmintenclr_el1, mask, set_expected);200	GUEST_ASSERT_BITMAP_REG(pmovsset_el0, mask, set_expected);201	GUEST_ASSERT_BITMAP_REG(pmovsclr_el0, mask, set_expected);202}203 204/*205 * Check if the bit in {PMCNTEN,PMINTEN,PMOVS}{SET,CLR} registers corresponding206 * to the specified counter (@pmc_idx) can be read/written as expected.207 * When @set_op is true, it tries to set the bit for the counter in208 * those registers by writing the SET registers (the bit won't be set209 * if the counter is not implemented though).210 * Otherwise, it tries to clear the bits in the registers by writing211 * the CLR registers.212 * Then, it checks if the values indicated in the registers are as expected.213 */214static void test_bitmap_pmu_regs(int pmc_idx, bool set_op)215{216	uint64_t pmcr_n, test_bit = BIT(pmc_idx);217	bool set_expected = false;218 219	if (set_op) {220		write_sysreg(test_bit, pmcntenset_el0);221		write_sysreg(test_bit, pmintenset_el1);222		write_sysreg(test_bit, pmovsset_el0);223 224		/* The bit will be set only if the counter is implemented */225		pmcr_n = get_pmcr_n(read_sysreg(pmcr_el0));226		set_expected = (pmc_idx < pmcr_n) ? true : false;227	} else {228		write_sysreg(test_bit, pmcntenclr_el0);229		write_sysreg(test_bit, pmintenclr_el1);230		write_sysreg(test_bit, pmovsclr_el0);231	}232	check_bitmap_pmu_regs(test_bit, set_expected);233}234 235/*236 * Tests for reading/writing registers for the (implemented) event counter237 * specified by @pmc_idx.238 */239static void test_access_pmc_regs(struct pmc_accessor *acc, int pmc_idx)240{241	uint64_t write_data, read_data;242 243	/* Disable all PMCs and reset all PMCs to zero. */244	pmu_disable_reset();245 246	/*247	 * Tests for reading/writing {PMCNTEN,PMINTEN,PMOVS}{SET,CLR}_EL1.248	 */249 250	/* Make sure that the bit in those registers are set to 0 */251	test_bitmap_pmu_regs(pmc_idx, false);252	/* Test if setting the bit in those registers works */253	test_bitmap_pmu_regs(pmc_idx, true);254	/* Test if clearing the bit in those registers works */255	test_bitmap_pmu_regs(pmc_idx, false);256 257	/*258	 * Tests for reading/writing the event type register.259	 */260 261	/*262	 * Set the event type register to an arbitrary value just for testing263	 * of reading/writing the register.264	 * Arm ARM says that for the event from 0x0000 to 0x003F,265	 * the value indicated in the PMEVTYPER<n>_EL0.evtCount field is266	 * the value written to the field even when the specified event267	 * is not supported.268	 */269	write_data = (ARMV8_PMU_EXCLUDE_EL1 | ARMV8_PMUV3_PERFCTR_INST_RETIRED);270	acc->write_typer(pmc_idx, write_data);271	read_data = acc->read_typer(pmc_idx);272	__GUEST_ASSERT(read_data == write_data,273		       "pmc_idx: 0x%x; acc_idx: 0x%lx; read_data: 0x%lx; write_data: 0x%lx",274		       pmc_idx, PMC_ACC_TO_IDX(acc), read_data, write_data);275 276	/*277	 * Tests for reading/writing the event count register.278	 */279 280	read_data = acc->read_cntr(pmc_idx);281 282	/* The count value must be 0, as it is disabled and reset */283	__GUEST_ASSERT(read_data == 0,284		       "pmc_idx: 0x%x; acc_idx: 0x%lx; read_data: 0x%lx",285		       pmc_idx, PMC_ACC_TO_IDX(acc), read_data);286 287	write_data = read_data + pmc_idx + 0x12345;288	acc->write_cntr(pmc_idx, write_data);289	read_data = acc->read_cntr(pmc_idx);290	__GUEST_ASSERT(read_data == write_data,291		       "pmc_idx: 0x%x; acc_idx: 0x%lx; read_data: 0x%lx; write_data: 0x%lx",292		       pmc_idx, PMC_ACC_TO_IDX(acc), read_data, write_data);293}294 295#define INVALID_EC	(-1ul)296uint64_t expected_ec = INVALID_EC;297 298static void guest_sync_handler(struct ex_regs *regs)299{300	uint64_t esr, ec;301 302	esr = read_sysreg(esr_el1);303	ec = (esr >> ESR_EC_SHIFT) & ESR_EC_MASK;304 305	__GUEST_ASSERT(expected_ec == ec,306			"PC: 0x%lx; ESR: 0x%lx; EC: 0x%lx; EC expected: 0x%lx",307			regs->pc, esr, ec, expected_ec);308 309	/* skip the trapping instruction */310	regs->pc += 4;311 312	/* Use INVALID_EC to indicate an exception occurred */313	expected_ec = INVALID_EC;314}315 316/*317 * Run the given operation that should trigger an exception with the318 * given exception class. The exception handler (guest_sync_handler)319 * will reset op_end_addr to 0, expected_ec to INVALID_EC, and skip320 * the instruction that trapped.321 */322#define TEST_EXCEPTION(ec, ops)				\323({							\324	GUEST_ASSERT(ec != INVALID_EC);			\325	WRITE_ONCE(expected_ec, ec);			\326	dsb(ish);					\327	ops;						\328	GUEST_ASSERT(expected_ec == INVALID_EC);	\329})330 331/*332 * Tests for reading/writing registers for the unimplemented event counter333 * specified by @pmc_idx (>= PMCR_EL0.N).334 */335static void test_access_invalid_pmc_regs(struct pmc_accessor *acc, int pmc_idx)336{337	/*338	 * Reading/writing the event count/type registers should cause339	 * an UNDEFINED exception.340	 */341	TEST_EXCEPTION(ESR_EC_UNKNOWN, acc->read_cntr(pmc_idx));342	TEST_EXCEPTION(ESR_EC_UNKNOWN, acc->write_cntr(pmc_idx, 0));343	TEST_EXCEPTION(ESR_EC_UNKNOWN, acc->read_typer(pmc_idx));344	TEST_EXCEPTION(ESR_EC_UNKNOWN, acc->write_typer(pmc_idx, 0));345	/*346	 * The bit corresponding to the (unimplemented) counter in347	 * {PMCNTEN,PMINTEN,PMOVS}{SET,CLR} registers should be RAZ.348	 */349	test_bitmap_pmu_regs(pmc_idx, 1);350	test_bitmap_pmu_regs(pmc_idx, 0);351}352 353/*354 * The guest is configured with PMUv3 with @expected_pmcr_n number of355 * event counters.356 * Check if @expected_pmcr_n is consistent with PMCR_EL0.N, and357 * if reading/writing PMU registers for implemented or unimplemented358 * counters works as expected.359 */360static void guest_code(uint64_t expected_pmcr_n)361{362	uint64_t pmcr, pmcr_n, unimp_mask;363	int i, pmc;364 365	__GUEST_ASSERT(expected_pmcr_n <= ARMV8_PMU_MAX_GENERAL_COUNTERS,366			"Expected PMCR.N: 0x%lx; ARMv8 general counters: 0x%x",367			expected_pmcr_n, ARMV8_PMU_MAX_GENERAL_COUNTERS);368 369	pmcr = read_sysreg(pmcr_el0);370	pmcr_n = get_pmcr_n(pmcr);371 372	/* Make sure that PMCR_EL0.N indicates the value userspace set */373	__GUEST_ASSERT(pmcr_n == expected_pmcr_n,374			"Expected PMCR.N: 0x%lx, PMCR.N: 0x%lx",375			expected_pmcr_n, pmcr_n);376 377	/*378	 * Make sure that (RAZ) bits corresponding to unimplemented event379	 * counters in {PMCNTEN,PMINTEN,PMOVS}{SET,CLR} registers are reset380	 * to zero.381	 * (NOTE: bits for implemented event counters are reset to UNKNOWN)382	 */383	unimp_mask = GENMASK_ULL(ARMV8_PMU_MAX_GENERAL_COUNTERS - 1, pmcr_n);384	check_bitmap_pmu_regs(unimp_mask, false);385 386	/*387	 * Tests for reading/writing PMU registers for implemented counters.388	 * Use each combination of PMEV{CNTR,TYPER}<n>_EL0 accessor functions.389	 */390	for (i = 0; i < ARRAY_SIZE(pmc_accessors); i++) {391		for (pmc = 0; pmc < pmcr_n; pmc++)392			test_access_pmc_regs(&pmc_accessors[i], pmc);393	}394 395	/*396	 * Tests for reading/writing PMU registers for unimplemented counters.397	 * Use each combination of PMEV{CNTR,TYPER}<n>_EL0 accessor functions.398	 */399	for (i = 0; i < ARRAY_SIZE(pmc_accessors); i++) {400		for (pmc = pmcr_n; pmc < ARMV8_PMU_MAX_GENERAL_COUNTERS; pmc++)401			test_access_invalid_pmc_regs(&pmc_accessors[i], pmc);402	}403 404	GUEST_DONE();405}406 407/* Create a VM that has one vCPU with PMUv3 configured. */408static void create_vpmu_vm(void *guest_code)409{410	struct kvm_vcpu_init init;411	uint8_t pmuver, ec;412	uint64_t dfr0, irq = 23;413	struct kvm_device_attr irq_attr = {414		.group = KVM_ARM_VCPU_PMU_V3_CTRL,415		.attr = KVM_ARM_VCPU_PMU_V3_IRQ,416		.addr = (uint64_t)&irq,417	};418	struct kvm_device_attr init_attr = {419		.group = KVM_ARM_VCPU_PMU_V3_CTRL,420		.attr = KVM_ARM_VCPU_PMU_V3_INIT,421	};422 423	/* The test creates the vpmu_vm multiple times. Ensure a clean state */424	memset(&vpmu_vm, 0, sizeof(vpmu_vm));425 426	vpmu_vm.vm = vm_create(1);427	vm_init_descriptor_tables(vpmu_vm.vm);428	for (ec = 0; ec < ESR_EC_NUM; ec++) {429		vm_install_sync_handler(vpmu_vm.vm, VECTOR_SYNC_CURRENT, ec,430					guest_sync_handler);431	}432 433	/* Create vCPU with PMUv3 */434	vm_ioctl(vpmu_vm.vm, KVM_ARM_PREFERRED_TARGET, &init);435	init.features[0] |= (1 << KVM_ARM_VCPU_PMU_V3);436	vpmu_vm.vcpu = aarch64_vcpu_add(vpmu_vm.vm, 0, &init, guest_code);437	vcpu_init_descriptor_tables(vpmu_vm.vcpu);438	vpmu_vm.gic_fd = vgic_v3_setup(vpmu_vm.vm, 1, 64);439	__TEST_REQUIRE(vpmu_vm.gic_fd >= 0,440		       "Failed to create vgic-v3, skipping");441 442	/* Make sure that PMUv3 support is indicated in the ID register */443	vcpu_get_reg(vpmu_vm.vcpu,444		     KVM_ARM64_SYS_REG(SYS_ID_AA64DFR0_EL1), &dfr0);445	pmuver = FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer), dfr0);446	TEST_ASSERT(pmuver != ID_AA64DFR0_EL1_PMUVer_IMP_DEF &&447		    pmuver >= ID_AA64DFR0_EL1_PMUVer_IMP,448		    "Unexpected PMUVER (0x%x) on the vCPU with PMUv3", pmuver);449 450	/* Initialize vPMU */451	vcpu_ioctl(vpmu_vm.vcpu, KVM_SET_DEVICE_ATTR, &irq_attr);452	vcpu_ioctl(vpmu_vm.vcpu, KVM_SET_DEVICE_ATTR, &init_attr);453}454 455static void destroy_vpmu_vm(void)456{457	close(vpmu_vm.gic_fd);458	kvm_vm_free(vpmu_vm.vm);459}460 461static void run_vcpu(struct kvm_vcpu *vcpu, uint64_t pmcr_n)462{463	struct ucall uc;464 465	vcpu_args_set(vcpu, 1, pmcr_n);466	vcpu_run(vcpu);467	switch (get_ucall(vcpu, &uc)) {468	case UCALL_ABORT:469		REPORT_GUEST_ASSERT(uc);470		break;471	case UCALL_DONE:472		break;473	default:474		TEST_FAIL("Unknown ucall %lu", uc.cmd);475		break;476	}477}478 479static void test_create_vpmu_vm_with_pmcr_n(uint64_t pmcr_n, bool expect_fail)480{481	struct kvm_vcpu *vcpu;482	uint64_t pmcr, pmcr_orig;483 484	create_vpmu_vm(guest_code);485	vcpu = vpmu_vm.vcpu;486 487	vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_PMCR_EL0), &pmcr_orig);488	pmcr = pmcr_orig;489 490	/*491	 * Setting a larger value of PMCR.N should not modify the field, and492	 * return a success.493	 */494	set_pmcr_n(&pmcr, pmcr_n);495	vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_PMCR_EL0), pmcr);496	vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_PMCR_EL0), &pmcr);497 498	if (expect_fail)499		TEST_ASSERT(pmcr_orig == pmcr,500			    "PMCR.N modified by KVM to a larger value (PMCR: 0x%lx) for pmcr_n: 0x%lx",501			    pmcr, pmcr_n);502	else503		TEST_ASSERT(pmcr_n == get_pmcr_n(pmcr),504			    "Failed to update PMCR.N to %lu (received: %lu)",505			    pmcr_n, get_pmcr_n(pmcr));506}507 508/*509 * Create a guest with one vCPU, set the PMCR_EL0.N for the vCPU to @pmcr_n,510 * and run the test.511 */512static void run_access_test(uint64_t pmcr_n)513{514	uint64_t sp;515	struct kvm_vcpu *vcpu;516	struct kvm_vcpu_init init;517 518	pr_debug("Test with pmcr_n %lu\n", pmcr_n);519 520	test_create_vpmu_vm_with_pmcr_n(pmcr_n, false);521	vcpu = vpmu_vm.vcpu;522 523	/* Save the initial sp to restore them later to run the guest again */524	vcpu_get_reg(vcpu, ARM64_CORE_REG(sp_el1), &sp);525 526	run_vcpu(vcpu, pmcr_n);527 528	/*529	 * Reset and re-initialize the vCPU, and run the guest code again to530	 * check if PMCR_EL0.N is preserved.531	 */532	vm_ioctl(vpmu_vm.vm, KVM_ARM_PREFERRED_TARGET, &init);533	init.features[0] |= (1 << KVM_ARM_VCPU_PMU_V3);534	aarch64_vcpu_setup(vcpu, &init);535	vcpu_init_descriptor_tables(vcpu);536	vcpu_set_reg(vcpu, ARM64_CORE_REG(sp_el1), sp);537	vcpu_set_reg(vcpu, ARM64_CORE_REG(regs.pc), (uint64_t)guest_code);538 539	run_vcpu(vcpu, pmcr_n);540 541	destroy_vpmu_vm();542}543 544static struct pmreg_sets validity_check_reg_sets[] = {545	PMREG_SET(SYS_PMCNTENSET_EL0, SYS_PMCNTENCLR_EL0),546	PMREG_SET(SYS_PMINTENSET_EL1, SYS_PMINTENCLR_EL1),547	PMREG_SET(SYS_PMOVSSET_EL0, SYS_PMOVSCLR_EL0),548};549 550/*551 * Create a VM, and check if KVM handles the userspace accesses of552 * the PMU register sets in @validity_check_reg_sets[] correctly.553 */554static void run_pmregs_validity_test(uint64_t pmcr_n)555{556	int i;557	struct kvm_vcpu *vcpu;558	uint64_t set_reg_id, clr_reg_id, reg_val;559	uint64_t valid_counters_mask, max_counters_mask;560 561	test_create_vpmu_vm_with_pmcr_n(pmcr_n, false);562	vcpu = vpmu_vm.vcpu;563 564	valid_counters_mask = get_counters_mask(pmcr_n);565	max_counters_mask = get_counters_mask(ARMV8_PMU_MAX_COUNTERS);566 567	for (i = 0; i < ARRAY_SIZE(validity_check_reg_sets); i++) {568		set_reg_id = validity_check_reg_sets[i].set_reg_id;569		clr_reg_id = validity_check_reg_sets[i].clr_reg_id;570 571		/*572		 * Test if the 'set' and 'clr' variants of the registers573		 * are initialized based on the number of valid counters.574		 */575		vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(set_reg_id), &reg_val);576		TEST_ASSERT((reg_val & (~valid_counters_mask)) == 0,577			    "Initial read of set_reg: 0x%llx has unimplemented counters enabled: 0x%lx",578			    KVM_ARM64_SYS_REG(set_reg_id), reg_val);579 580		vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(clr_reg_id), &reg_val);581		TEST_ASSERT((reg_val & (~valid_counters_mask)) == 0,582			    "Initial read of clr_reg: 0x%llx has unimplemented counters enabled: 0x%lx",583			    KVM_ARM64_SYS_REG(clr_reg_id), reg_val);584 585		/*586		 * Using the 'set' variant, force-set the register to the587		 * max number of possible counters and test if KVM discards588		 * the bits for unimplemented counters as it should.589		 */590		vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(set_reg_id), max_counters_mask);591 592		vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(set_reg_id), &reg_val);593		TEST_ASSERT((reg_val & (~valid_counters_mask)) == 0,594			    "Read of set_reg: 0x%llx has unimplemented counters enabled: 0x%lx",595			    KVM_ARM64_SYS_REG(set_reg_id), reg_val);596 597		vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(clr_reg_id), &reg_val);598		TEST_ASSERT((reg_val & (~valid_counters_mask)) == 0,599			    "Read of clr_reg: 0x%llx has unimplemented counters enabled: 0x%lx",600			    KVM_ARM64_SYS_REG(clr_reg_id), reg_val);601	}602 603	destroy_vpmu_vm();604}605 606/*607 * Create a guest with one vCPU, and attempt to set the PMCR_EL0.N for608 * the vCPU to @pmcr_n, which is larger than the host value.609 * The attempt should fail as @pmcr_n is too big to set for the vCPU.610 */611static void run_error_test(uint64_t pmcr_n)612{613	pr_debug("Error test with pmcr_n %lu (larger than the host)\n", pmcr_n);614 615	test_create_vpmu_vm_with_pmcr_n(pmcr_n, true);616	destroy_vpmu_vm();617}618 619/*620 * Return the default number of implemented PMU event counters excluding621 * the cycle counter (i.e. PMCR_EL0.N value) for the guest.622 */623static uint64_t get_pmcr_n_limit(void)624{625	uint64_t pmcr;626 627	create_vpmu_vm(guest_code);628	vcpu_get_reg(vpmu_vm.vcpu, KVM_ARM64_SYS_REG(SYS_PMCR_EL0), &pmcr);629	destroy_vpmu_vm();630	return get_pmcr_n(pmcr);631}632 633int main(void)634{635	uint64_t i, pmcr_n;636 637	TEST_REQUIRE(kvm_has_cap(KVM_CAP_ARM_PMU_V3));638 639	pmcr_n = get_pmcr_n_limit();640	for (i = 0; i <= pmcr_n; i++) {641		run_access_test(i);642		run_pmregs_validity_test(i);643	}644 645	for (i = pmcr_n + 1; i < ARMV8_PMU_MAX_COUNTERS; i++)646		run_error_test(i);647 648	return 0;649}650