Add a new test case to the vpmu_counter_access test to check if PMU registers or their bits for unimplemented counters are not accessible or are RAZ, as expected.
Signed-off-by: Reiji Watanabe <[email protected]> --- .../kvm/aarch64/vpmu_counter_access.c | 103 +++++++++++++++++- .../selftests/kvm/include/aarch64/processor.h | 1 + 2 files changed, 98 insertions(+), 6 deletions(-) diff --git a/tools/testing/selftests/kvm/aarch64/vpmu_counter_access.c b/tools/testing/selftests/kvm/aarch64/vpmu_counter_access.c index 5b9d837f903a..af1abdfa2be2 100644 --- a/tools/testing/selftests/kvm/aarch64/vpmu_counter_access.c +++ b/tools/testing/selftests/kvm/aarch64/vpmu_counter_access.c @@ -5,8 +5,8 @@ * Copyright (c) 2022 Google LLC. * * This test checks if the guest can see the same number of the PMU event - * counters (PMCR_EL1.N) that userspace sets, and if the guest can access - * those counters. + * counters (PMCR_EL1.N) that userspace sets, if the guest can access + * those counters, and if the guest cannot access any other counters. * This test runs only when KVM_CAP_ARM_PMU_V3 is supported on the host. */ #include <kvm_util.h> @@ -179,6 +179,51 @@ struct pmc_accessor pmc_accessors[] = { { read_sel_evcntr, write_pmevcntrn, read_sel_evtyper, write_pmevtypern }, }; +#define INVALID_EC (-1ul) +uint64_t expected_ec = INVALID_EC; +uint64_t op_end_addr; + +static void guest_sync_handler(struct ex_regs *regs) +{ + uint64_t esr, ec; + + esr = read_sysreg(esr_el1); + ec = (esr >> ESR_EC_SHIFT) & ESR_EC_MASK; + GUEST_ASSERT_4(op_end_addr && (expected_ec == ec), + regs->pc, esr, ec, expected_ec); + + /* Will go back to op_end_addr after the handler exits */ + regs->pc = op_end_addr; + + /* + * Clear op_end_addr, and setting expected_ec to INVALID_EC + * as a sign that an exception has occurred. + */ + op_end_addr = 0; + expected_ec = INVALID_EC; +} + +/* + * Run the given operation that should trigger an exception with the + * given exception class. The exception handler (guest_sync_handler) + * will reset op_end_addr to 0, and expected_ec to INVALID_EC, and + * will come back to the instruction at the @done_label. + * The @done_label must be a unique label in this test program. + */ +#define TEST_EXCEPTION(ec, ops, done_label) \ +{ \ + extern int done_label; \ + \ + WRITE_ONCE(op_end_addr, (uint64_t)&done_label); \ + GUEST_ASSERT(ec != INVALID_EC); \ + WRITE_ONCE(expected_ec, ec); \ + dsb(ish); \ + ops; \ + asm volatile(#done_label":"); \ + GUEST_ASSERT(!op_end_addr); \ + GUEST_ASSERT(expected_ec == INVALID_EC); \ +} + static void pmu_disable_reset(void) { uint64_t pmcr = read_sysreg(pmcr_el0); @@ -352,16 +397,38 @@ static void test_access_pmc_regs(struct pmc_accessor *acc, int pmc_idx) pmc_idx, acc, read_data, read_data_prev); } +/* + * Tests for reading/writing registers for the unimplemented event counter + * specified by @pmc_idx (>= PMCR_EL1.N). + */ +static void test_access_invalid_pmc_regs(struct pmc_accessor *acc, int pmc_idx) +{ + /* + * Reading/writing the event count/type registers should cause + * an UNDEFINED exception. + */ + TEST_EXCEPTION(ESR_EC_UNKNOWN, acc->read_cntr(pmc_idx), inv_rd_cntr); + TEST_EXCEPTION(ESR_EC_UNKNOWN, acc->write_cntr(pmc_idx, 0), inv_wr_cntr); + TEST_EXCEPTION(ESR_EC_UNKNOWN, acc->read_typer(pmc_idx), inv_rd_typer); + TEST_EXCEPTION(ESR_EC_UNKNOWN, acc->write_typer(pmc_idx, 0), inv_wr_typer); + /* + * The bit corresponding to the (unimplemented) counter in + * {PMCNTEN,PMOVS}{SET,CLR}_EL1 registers should be RAZ. + */ + test_bitmap_pmu_regs(pmc_idx, 1); + test_bitmap_pmu_regs(pmc_idx, 0); +} + /* * The guest is configured with PMUv3 with @expected_pmcr_n number of * event counters. * Check if @expected_pmcr_n is consistent with PMCR_EL0.N, and - * if reading/writing PMU registers for implemented counters can work - * as expected. + * if reading/writing PMU registers for implemented or unimplemented + * counters can work as expected. */ static void guest_code(uint64_t expected_pmcr_n) { - uint64_t pmcr, pmcr_n; + uint64_t pmcr, pmcr_n, unimp_mask; int i, pmc; GUEST_ASSERT(expected_pmcr_n <= ARMV8_PMU_MAX_GENERAL_COUNTERS); @@ -372,6 +439,14 @@ static void guest_code(uint64_t expected_pmcr_n) /* Make sure that PMCR_EL0.N indicates the value userspace set */ GUEST_ASSERT_2(pmcr_n == expected_pmcr_n, pmcr_n, expected_pmcr_n); + /* + * Make sure that (RAZ) bits corresponding to unimplemented event + * counters in {PMCNTEN,PMOVS}{SET,CLR}_EL1 registers are reset to zero. + * (NOTE: bits for implemented event counters are reset to UNKNOWN) + */ + unimp_mask = GENMASK_ULL(ARMV8_PMU_MAX_GENERAL_COUNTERS - 1, pmcr_n); + check_bitmap_pmu_regs(unimp_mask, false); + /* * Tests for reading/writing PMU registers for implemented counters. * Use each combination of PMEVT{CNTR,TYPER}<n>_EL0 accessor functions. @@ -381,6 +456,14 @@ static void guest_code(uint64_t expected_pmcr_n) test_access_pmc_regs(&pmc_accessors[i], pmc); } + /* + * Tests for reading/writing PMU registers for unimplemented counters. + * Use each combination of PMEVT{CNTR,TYPER}<n>_EL0 accessor functions. + */ + for (i = 0; i < ARRAY_SIZE(pmc_accessors); i++) { + for (pmc = pmcr_n; pmc < ARMV8_PMU_MAX_GENERAL_COUNTERS; pmc++) + test_access_invalid_pmc_regs(&pmc_accessors[i], pmc); + } GUEST_DONE(); } @@ -394,7 +477,7 @@ static struct kvm_vm *create_vpmu_vm(void *guest_code, struct kvm_vcpu **vcpup, struct kvm_vm *vm; struct kvm_vcpu *vcpu; struct kvm_vcpu_init init; - uint8_t pmuver; + uint8_t pmuver, ec; uint64_t dfr0, irq = 23; struct kvm_device_attr irq_attr = { .group = KVM_ARM_VCPU_PMU_V3_CTRL, @@ -408,11 +491,18 @@ static struct kvm_vm *create_vpmu_vm(void *guest_code, struct kvm_vcpu **vcpup, vm = vm_create(1); ucall_init(vm, NULL); + vm_init_descriptor_tables(vm); + /* Catch exceptions for easier debugging */ + for (ec = 0; ec < ESR_EC_NUM; ec++) { + vm_install_sync_handler(vm, VECTOR_SYNC_CURRENT, ec, + guest_sync_handler); + } /* Create vCPU with PMUv3 */ vm_ioctl(vm, KVM_ARM_PREFERRED_TARGET, &init); init.features[0] |= (1 << KVM_ARM_VCPU_PMU_V3); vcpu = aarch64_vcpu_add(vm, 0, &init, guest_code); + vcpu_init_descriptor_tables(vcpu); *gic_fd = vgic_v3_setup(vm, 1, 64, GICD_BASE_GPA, GICR_BASE_GPA); /* Make sure that PMUv3 support is indicated in the ID register */ @@ -481,6 +571,7 @@ static void run_test(uint64_t pmcr_n) vm_ioctl(vm, KVM_ARM_PREFERRED_TARGET, &init); init.features[0] |= (1 << KVM_ARM_VCPU_PMU_V3); aarch64_vcpu_setup(vcpu, &init); + vcpu_init_descriptor_tables(vcpu); vcpu_set_reg(vcpu, ARM64_CORE_REG(sp_el1), sp); vcpu_set_reg(vcpu, ARM64_CORE_REG(regs.pc), (uint64_t)guest_code); diff --git a/tools/testing/selftests/kvm/include/aarch64/processor.h b/tools/testing/selftests/kvm/include/aarch64/processor.h index 5f977528e09c..52d87809356c 100644 --- a/tools/testing/selftests/kvm/include/aarch64/processor.h +++ b/tools/testing/selftests/kvm/include/aarch64/processor.h @@ -104,6 +104,7 @@ enum { #define ESR_EC_SHIFT 26 #define ESR_EC_MASK (ESR_EC_NUM - 1) +#define ESR_EC_UNKNOWN 0x0 #define ESR_EC_SVC64 0x15 #define ESR_EC_IABT 0x21 #define ESR_EC_DABT 0x25 -- 2.39.0.314.g84b9a713c41-goog _______________________________________________ kvmarm mailing list [email protected] https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
