diff options
| -rw-r--r-- | tools/testing/selftests/kvm/Makefile.kvm | 1 | ||||
| -rw-r--r-- | tools/testing/selftests/kvm/include/x86/apic.h | 3 | ||||
| -rw-r--r-- | tools/testing/selftests/kvm/x86/xapic_tpr_test.c | 276 |
3 files changed, 280 insertions, 0 deletions
diff --git a/tools/testing/selftests/kvm/Makefile.kvm b/tools/testing/selftests/kvm/Makefile.kvm index ba5c2b643efa..3789890421bd 100644 --- a/tools/testing/selftests/kvm/Makefile.kvm +++ b/tools/testing/selftests/kvm/Makefile.kvm @@ -124,6 +124,7 @@ TEST_GEN_PROGS_x86 += x86/vmx_set_nested_state_test TEST_GEN_PROGS_x86 += x86/apic_bus_clock_test TEST_GEN_PROGS_x86 += x86/xapic_ipi_test TEST_GEN_PROGS_x86 += x86/xapic_state_test +TEST_GEN_PROGS_x86 += x86/xapic_tpr_test TEST_GEN_PROGS_x86 += x86/xcr0_cpuid_test TEST_GEN_PROGS_x86 += x86/xss_msr_test TEST_GEN_PROGS_x86 += x86/debug_regs diff --git a/tools/testing/selftests/kvm/include/x86/apic.h b/tools/testing/selftests/kvm/include/x86/apic.h index 80fe9f69b38d..e9b9aebaac97 100644 --- a/tools/testing/selftests/kvm/include/x86/apic.h +++ b/tools/testing/selftests/kvm/include/x86/apic.h @@ -28,6 +28,8 @@ #define GET_APIC_ID_FIELD(x) (((x) >> 24) & 0xFF) #define APIC_TASKPRI 0x80 #define APIC_PROCPRI 0xA0 +#define GET_APIC_PRI(x) (((x) & GENMASK(7, 4)) >> 4) +#define SET_APIC_PRI(x, y) (((x) & ~GENMASK(7, 4)) | (y << 4)) #define APIC_EOI 0xB0 #define APIC_SPIV 0xF0 #define APIC_SPIV_FOCUS_DISABLED (1 << 9) @@ -67,6 +69,7 @@ #define APIC_TMICT 0x380 #define APIC_TMCCT 0x390 #define APIC_TDCR 0x3E0 +#define APIC_SELF_IPI 0x3F0 void apic_disable(void); void xapic_enable(void); diff --git a/tools/testing/selftests/kvm/x86/xapic_tpr_test.c b/tools/testing/selftests/kvm/x86/xapic_tpr_test.c new file mode 100644 index 000000000000..3862134d9d40 --- /dev/null +++ b/tools/testing/selftests/kvm/x86/xapic_tpr_test.c @@ -0,0 +1,276 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include <fcntl.h> +#include <stdatomic.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/ioctl.h> +#include <unistd.h> + +#include "apic.h" +#include "kvm_util.h" +#include "processor.h" +#include "test_util.h" + +static bool is_x2apic; + +#define IRQ_VECTOR 0x20 + +/* See also the comment at similar assertion in memslot_perf_test.c */ +static_assert(ATOMIC_INT_LOCK_FREE == 2, "atomic int is not lockless"); + +static atomic_uint tpr_guest_irq_sync_val; + +static void tpr_guest_irq_sync_flag_reset(void) +{ + atomic_store_explicit(&tpr_guest_irq_sync_val, 0, + memory_order_release); +} + +static unsigned int tpr_guest_irq_sync_val_get(void) +{ + return atomic_load_explicit(&tpr_guest_irq_sync_val, + memory_order_acquire); +} + +static void tpr_guest_irq_sync_val_inc(void) +{ + atomic_fetch_add_explicit(&tpr_guest_irq_sync_val, 1, + memory_order_acq_rel); +} + +static void tpr_guest_irq_handler_xapic(struct ex_regs *regs) +{ + tpr_guest_irq_sync_val_inc(); + + xapic_write_reg(APIC_EOI, 0); +} + +static void tpr_guest_irq_handler_x2apic(struct ex_regs *regs) +{ + tpr_guest_irq_sync_val_inc(); + + x2apic_write_reg(APIC_EOI, 0); +} + +static void tpr_guest_irq_queue(void) +{ + if (is_x2apic) { + x2apic_write_reg(APIC_SELF_IPI, IRQ_VECTOR); + } else { + uint32_t icr, icr2; + + icr = APIC_DEST_SELF | APIC_DEST_PHYSICAL | APIC_DM_FIXED | + IRQ_VECTOR; + icr2 = 0; + + xapic_write_reg(APIC_ICR2, icr2); + xapic_write_reg(APIC_ICR, icr); + } +} + +static uint8_t tpr_guest_tpr_get(void) +{ + uint32_t taskpri; + + if (is_x2apic) + taskpri = x2apic_read_reg(APIC_TASKPRI); + else + taskpri = xapic_read_reg(APIC_TASKPRI); + + return GET_APIC_PRI(taskpri); +} + +static uint8_t tpr_guest_ppr_get(void) +{ + uint32_t procpri; + + if (is_x2apic) + procpri = x2apic_read_reg(APIC_PROCPRI); + else + procpri = xapic_read_reg(APIC_PROCPRI); + + return GET_APIC_PRI(procpri); +} + +static uint8_t tpr_guest_cr8_get(void) +{ + uint64_t cr8; + + asm volatile ("mov %%cr8, %[cr8]\n\t" : [cr8] "=r"(cr8)); + + return cr8 & GENMASK(3, 0); +} + +static void tpr_guest_check_tpr_ppr_cr8_equal(void) +{ + uint8_t tpr; + + tpr = tpr_guest_tpr_get(); + + GUEST_ASSERT_EQ(tpr_guest_ppr_get(), tpr); + GUEST_ASSERT_EQ(tpr_guest_cr8_get(), tpr); +} + +static void tpr_guest_code(void) +{ + cli(); + + if (is_x2apic) + x2apic_enable(); + else + xapic_enable(); + + GUEST_ASSERT_EQ(tpr_guest_tpr_get(), 0); + tpr_guest_check_tpr_ppr_cr8_equal(); + + tpr_guest_irq_queue(); + + /* TPR = 0 but IRQ masked by IF=0, should not fire */ + udelay(1000); + GUEST_ASSERT_EQ(tpr_guest_irq_sync_val_get(), 0); + + sti(); + + /* IF=1 now, IRQ should fire */ + while (tpr_guest_irq_sync_val_get() == 0) + cpu_relax(); + GUEST_ASSERT_EQ(tpr_guest_irq_sync_val_get(), 1); + + GUEST_SYNC(true); + tpr_guest_check_tpr_ppr_cr8_equal(); + + tpr_guest_irq_queue(); + + /* IRQ masked by barely high enough TPR now, should not fire */ + udelay(1000); + GUEST_ASSERT_EQ(tpr_guest_irq_sync_val_get(), 1); + + GUEST_SYNC(false); + tpr_guest_check_tpr_ppr_cr8_equal(); + + /* TPR barely low enough now to unmask IRQ, should fire */ + while (tpr_guest_irq_sync_val_get() == 1) + cpu_relax(); + GUEST_ASSERT_EQ(tpr_guest_irq_sync_val_get(), 2); + + GUEST_DONE(); +} + +static uint8_t lapic_tpr_get(struct kvm_lapic_state *xapic) +{ + return GET_APIC_PRI(*((u32 *)&xapic->regs[APIC_TASKPRI])); +} + +static void lapic_tpr_set(struct kvm_lapic_state *xapic, uint8_t val) +{ + u32 *taskpri = (u32 *)&xapic->regs[APIC_TASKPRI]; + + *taskpri = SET_APIC_PRI(*taskpri, val); +} + +static uint8_t sregs_tpr(struct kvm_sregs *sregs) +{ + return sregs->cr8 & GENMASK(3, 0); +} + +static void test_tpr_check_tpr_zero(struct kvm_vcpu *vcpu) +{ + struct kvm_lapic_state xapic; + + vcpu_ioctl(vcpu, KVM_GET_LAPIC, &xapic); + + TEST_ASSERT_EQ(lapic_tpr_get(&xapic), 0); +} + +static void test_tpr_check_tpr_cr8_equal(struct kvm_vcpu *vcpu) +{ + struct kvm_sregs sregs; + struct kvm_lapic_state xapic; + + vcpu_sregs_get(vcpu, &sregs); + vcpu_ioctl(vcpu, KVM_GET_LAPIC, &xapic); + + TEST_ASSERT_EQ(sregs_tpr(&sregs), lapic_tpr_get(&xapic)); +} + +static void test_tpr_set_tpr_for_irq(struct kvm_vcpu *vcpu, bool mask) +{ + struct kvm_lapic_state xapic; + uint8_t tpr; + + static_assert(IRQ_VECTOR >= 16, "invalid IRQ vector number"); + tpr = IRQ_VECTOR / 16; + if (!mask) + tpr--; + + vcpu_ioctl(vcpu, KVM_GET_LAPIC, &xapic); + lapic_tpr_set(&xapic, tpr); + vcpu_ioctl(vcpu, KVM_SET_LAPIC, &xapic); +} + +static void test_tpr(bool __is_x2apic) +{ + struct kvm_vcpu *vcpu; + struct kvm_vm *vm; + bool done = false; + + is_x2apic = __is_x2apic; + + vm = vm_create_with_one_vcpu(&vcpu, tpr_guest_code); + if (is_x2apic) { + vm_install_exception_handler(vm, IRQ_VECTOR, + tpr_guest_irq_handler_x2apic); + } else { + vm_install_exception_handler(vm, IRQ_VECTOR, + tpr_guest_irq_handler_xapic); + vcpu_clear_cpuid_feature(vcpu, X86_FEATURE_X2APIC); + virt_pg_map(vm, APIC_DEFAULT_GPA, APIC_DEFAULT_GPA); + } + + sync_global_to_guest(vcpu->vm, is_x2apic); + + /* According to the SDM/APM the TPR value at reset is 0 */ + test_tpr_check_tpr_zero(vcpu); + test_tpr_check_tpr_cr8_equal(vcpu); + + tpr_guest_irq_sync_flag_reset(); + sync_global_to_guest(vcpu->vm, tpr_guest_irq_sync_val); + + while (!done) { + struct ucall uc; + + alarm(2); + vcpu_run(vcpu); + alarm(0); + + switch (get_ucall(vcpu, &uc)) { + case UCALL_ABORT: + REPORT_GUEST_ASSERT(uc); + break; + case UCALL_DONE: + test_tpr_check_tpr_cr8_equal(vcpu); + done = true; + break; + case UCALL_SYNC: + test_tpr_check_tpr_cr8_equal(vcpu); + test_tpr_set_tpr_for_irq(vcpu, uc.args[1]); + break; + default: + TEST_FAIL("Unknown ucall result 0x%lx", uc.cmd); + break; + } + } + kvm_vm_free(vm); +} + +int main(int argc, char *argv[]) +{ + /* + * Use separate VMs for the xAPIC and x2APIC tests so that x2APIC can + * be fully hidden from the guest. KVM disallows changing CPUID after + * KVM_RUN and AVIC is disabled if _any_ vCPU is allowed to use x2APIC. + */ + test_tpr(false); + test_tpr(true); +} |