diff options
Diffstat (limited to 'tools/testing/selftests/kvm/x86_64/evmcs_test.c')
| -rw-r--r-- | tools/testing/selftests/kvm/x86_64/evmcs_test.c | 275 |
1 files changed, 275 insertions, 0 deletions
diff --git a/tools/testing/selftests/kvm/x86_64/evmcs_test.c b/tools/testing/selftests/kvm/x86_64/evmcs_test.c new file mode 100644 index 000000000..99bc20224 --- /dev/null +++ b/tools/testing/selftests/kvm/x86_64/evmcs_test.c @@ -0,0 +1,275 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2018, Red Hat, Inc. + * + * Tests for Enlightened VMCS, including nested guest state. + */ +#define _GNU_SOURCE /* for program_invocation_short_name */ +#include <fcntl.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/ioctl.h> +#include <linux/bitmap.h> + +#include "test_util.h" + +#include "kvm_util.h" + +#include "vmx.h" + +static int ud_count; + +static void guest_ud_handler(struct ex_regs *regs) +{ + ud_count++; + regs->rip += 3; /* VMLAUNCH */ +} + +static void guest_nmi_handler(struct ex_regs *regs) +{ +} + +/* Exits to L1 destroy GRPs! */ +static inline void rdmsr_fs_base(void) +{ + __asm__ __volatile__ ("mov $0xc0000100, %%rcx; rdmsr" : : : + "rax", "rbx", "rcx", "rdx", + "rsi", "rdi", "r8", "r9", "r10", "r11", "r12", + "r13", "r14", "r15"); +} +static inline void rdmsr_gs_base(void) +{ + __asm__ __volatile__ ("mov $0xc0000101, %%rcx; rdmsr" : : : + "rax", "rbx", "rcx", "rdx", + "rsi", "rdi", "r8", "r9", "r10", "r11", "r12", + "r13", "r14", "r15"); +} + +void l2_guest_code(void) +{ + GUEST_SYNC(7); + + GUEST_SYNC(8); + + /* Forced exit to L1 upon restore */ + GUEST_SYNC(9); + + vmcall(); + + /* MSR-Bitmap tests */ + rdmsr_fs_base(); /* intercepted */ + rdmsr_fs_base(); /* intercepted */ + rdmsr_gs_base(); /* not intercepted */ + vmcall(); + rdmsr_gs_base(); /* intercepted */ + + /* Done, exit to L1 and never come back. */ + vmcall(); +} + +void guest_code(struct vmx_pages *vmx_pages) +{ +#define L2_GUEST_STACK_SIZE 64 + unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE]; + + x2apic_enable(); + + GUEST_SYNC(1); + GUEST_SYNC(2); + + enable_vp_assist(vmx_pages->vp_assist_gpa, vmx_pages->vp_assist); + + GUEST_ASSERT(vmx_pages->vmcs_gpa); + GUEST_ASSERT(prepare_for_vmx_operation(vmx_pages)); + GUEST_SYNC(3); + GUEST_ASSERT(load_vmcs(vmx_pages)); + GUEST_ASSERT(vmptrstz() == vmx_pages->enlightened_vmcs_gpa); + + GUEST_SYNC(4); + GUEST_ASSERT(vmptrstz() == vmx_pages->enlightened_vmcs_gpa); + + prepare_vmcs(vmx_pages, l2_guest_code, + &l2_guest_stack[L2_GUEST_STACK_SIZE]); + + GUEST_SYNC(5); + GUEST_ASSERT(vmptrstz() == vmx_pages->enlightened_vmcs_gpa); + current_evmcs->revision_id = -1u; + GUEST_ASSERT(vmlaunch()); + current_evmcs->revision_id = EVMCS_VERSION; + GUEST_SYNC(6); + + vmwrite(PIN_BASED_VM_EXEC_CONTROL, vmreadz(PIN_BASED_VM_EXEC_CONTROL) | + PIN_BASED_NMI_EXITING); + + GUEST_ASSERT(!vmlaunch()); + GUEST_ASSERT(vmptrstz() == vmx_pages->enlightened_vmcs_gpa); + + /* + * NMI forces L2->L1 exit, resuming L2 and hope that EVMCS is + * up-to-date (RIP points where it should and not at the beginning + * of l2_guest_code(). GUEST_SYNC(9) checkes that. + */ + GUEST_ASSERT(!vmresume()); + + GUEST_SYNC(10); + + GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL); + current_evmcs->guest_rip += 3; /* vmcall */ + + /* Intercept RDMSR 0xc0000100 */ + vmwrite(CPU_BASED_VM_EXEC_CONTROL, vmreadz(CPU_BASED_VM_EXEC_CONTROL) | + CPU_BASED_USE_MSR_BITMAPS); + set_bit(MSR_FS_BASE & 0x1fff, vmx_pages->msr + 0x400); + GUEST_ASSERT(!vmresume()); + GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_MSR_READ); + current_evmcs->guest_rip += 2; /* rdmsr */ + + /* Enable enlightened MSR bitmap */ + current_evmcs->hv_enlightenments_control.msr_bitmap = 1; + GUEST_ASSERT(!vmresume()); + GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_MSR_READ); + current_evmcs->guest_rip += 2; /* rdmsr */ + + /* Intercept RDMSR 0xc0000101 without telling KVM about it */ + set_bit(MSR_GS_BASE & 0x1fff, vmx_pages->msr + 0x400); + /* Make sure HV_VMX_ENLIGHTENED_CLEAN_FIELD_MSR_BITMAP is set */ + current_evmcs->hv_clean_fields |= HV_VMX_ENLIGHTENED_CLEAN_FIELD_MSR_BITMAP; + GUEST_ASSERT(!vmresume()); + /* Make sure we don't see EXIT_REASON_MSR_READ here so eMSR bitmap works */ + GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL); + current_evmcs->guest_rip += 3; /* vmcall */ + + /* Now tell KVM we've changed MSR-Bitmap */ + current_evmcs->hv_clean_fields &= ~HV_VMX_ENLIGHTENED_CLEAN_FIELD_MSR_BITMAP; + GUEST_ASSERT(!vmresume()); + GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_MSR_READ); + current_evmcs->guest_rip += 2; /* rdmsr */ + + GUEST_ASSERT(!vmresume()); + GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL); + GUEST_SYNC(11); + + /* Try enlightened vmptrld with an incorrect GPA */ + evmcs_vmptrld(0xdeadbeef, vmx_pages->enlightened_vmcs); + GUEST_ASSERT(vmlaunch()); + GUEST_ASSERT(ud_count == 1); + GUEST_DONE(); +} + +void inject_nmi(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_events events; + + vcpu_events_get(vcpu, &events); + + events.nmi.pending = 1; + events.flags |= KVM_VCPUEVENT_VALID_NMI_PENDING; + + vcpu_events_set(vcpu, &events); +} + +static struct kvm_vcpu *save_restore_vm(struct kvm_vm *vm, + struct kvm_vcpu *vcpu) +{ + struct kvm_regs regs1, regs2; + struct kvm_x86_state *state; + + state = vcpu_save_state(vcpu); + memset(®s1, 0, sizeof(regs1)); + vcpu_regs_get(vcpu, ®s1); + + kvm_vm_release(vm); + + /* Restore state in a new VM. */ + vcpu = vm_recreate_with_one_vcpu(vm); + vcpu_set_hv_cpuid(vcpu); + vcpu_enable_evmcs(vcpu); + vcpu_load_state(vcpu, state); + kvm_x86_state_cleanup(state); + + memset(®s2, 0, sizeof(regs2)); + vcpu_regs_get(vcpu, ®s2); + TEST_ASSERT(!memcmp(®s1, ®s2, sizeof(regs2)), + "Unexpected register values after vcpu_load_state; rdi: %lx rsi: %lx", + (ulong) regs2.rdi, (ulong) regs2.rsi); + return vcpu; +} + +int main(int argc, char *argv[]) +{ + vm_vaddr_t vmx_pages_gva = 0; + + struct kvm_vcpu *vcpu; + struct kvm_vm *vm; + struct kvm_run *run; + struct ucall uc; + int stage; + + vm = vm_create_with_one_vcpu(&vcpu, guest_code); + + TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_VMX)); + TEST_REQUIRE(kvm_has_cap(KVM_CAP_NESTED_STATE)); + TEST_REQUIRE(kvm_has_cap(KVM_CAP_HYPERV_ENLIGHTENED_VMCS)); + + vcpu_set_hv_cpuid(vcpu); + vcpu_enable_evmcs(vcpu); + + vcpu_alloc_vmx(vm, &vmx_pages_gva); + vcpu_args_set(vcpu, 1, vmx_pages_gva); + + vm_init_descriptor_tables(vm); + vcpu_init_descriptor_tables(vcpu); + vm_install_exception_handler(vm, UD_VECTOR, guest_ud_handler); + vm_install_exception_handler(vm, NMI_VECTOR, guest_nmi_handler); + + pr_info("Running L1 which uses EVMCS to run L2\n"); + + for (stage = 1;; stage++) { + run = vcpu->run; + + vcpu_run(vcpu); + TEST_ASSERT(run->exit_reason == KVM_EXIT_IO, + "Stage %d: unexpected exit reason: %u (%s),\n", + stage, run->exit_reason, + exit_reason_str(run->exit_reason)); + + switch (get_ucall(vcpu, &uc)) { + case UCALL_ABORT: + REPORT_GUEST_ASSERT(uc); + /* NOT REACHED */ + case UCALL_SYNC: + break; + case UCALL_DONE: + goto done; + default: + TEST_FAIL("Unknown ucall %lu", uc.cmd); + } + + /* UCALL_SYNC is handled here. */ + TEST_ASSERT(!strcmp((const char *)uc.args[0], "hello") && + uc.args[1] == stage, "Stage %d: Unexpected register values vmexit, got %lx", + stage, (ulong)uc.args[1]); + + vcpu = save_restore_vm(vm, vcpu); + + /* Force immediate L2->L1 exit before resuming */ + if (stage == 8) { + pr_info("Injecting NMI into L1 before L2 had a chance to run after restore\n"); + inject_nmi(vcpu); + } + + /* + * Do KVM_GET_NESTED_STATE/KVM_SET_NESTED_STATE for a freshly + * restored VM (before the first KVM_RUN) to check that + * KVM_STATE_NESTED_EVMCS is not lost. + */ + if (stage == 9) { + pr_info("Trying extra KVM_GET_NESTED_STATE/KVM_SET_NESTED_STATE cycle\n"); + vcpu = save_restore_vm(vm, vcpu); + } + } + +done: + kvm_vm_free(vm); +} |