1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2025, Google LLC. 4 * 5 * This test verifies that L1 fails to enter L2 with an invalid CR3, and 6 * succeeds otherwise. 7 */ 8 #include "kvm_util.h" 9 #include "vmx.h" 10 #include "svm_util.h" 11 #include "kselftest.h" 12 13 14 static void l2_guest_code(void) 15 { 16 vmcall(); 17 } 18 19 static void l1_svm_code(struct svm_test_data *svm) 20 { 21 uintptr_t save_cr3; 22 23 generic_svm_setup(svm, l2_guest_code); 24 25 /* Try to run L2 with invalid CR3 and make sure it fails */ 26 save_cr3 = svm->vmcb->save.cr3; 27 svm->vmcb->save.cr3 = -1ull; 28 run_guest(svm->vmcb, svm->vmcb_gpa); 29 GUEST_ASSERT(svm->vmcb->control.exit_code == SVM_EXIT_ERR); 30 31 /* Now restore CR3 and make sure L2 runs successfully */ 32 svm->vmcb->save.cr3 = save_cr3; 33 run_guest(svm->vmcb, svm->vmcb_gpa); 34 GUEST_ASSERT(svm->vmcb->control.exit_code == SVM_EXIT_VMMCALL); 35 36 GUEST_DONE(); 37 } 38 39 static void l1_vmx_code(struct vmx_pages *vmx_pages) 40 { 41 uintptr_t save_cr3; 42 43 GUEST_ASSERT(prepare_for_vmx_operation(vmx_pages)); 44 GUEST_ASSERT(load_vmcs(vmx_pages)); 45 46 prepare_vmcs(vmx_pages, l2_guest_code); 47 48 /* Try to run L2 with invalid CR3 and make sure it fails */ 49 save_cr3 = vmreadz(GUEST_CR3); 50 vmwrite(GUEST_CR3, -1ull); 51 GUEST_ASSERT(!vmlaunch()); 52 GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == 53 (EXIT_REASON_FAILED_VMENTRY | EXIT_REASON_INVALID_STATE)); 54 55 /* Now restore CR3 and make sure L2 runs successfully */ 56 vmwrite(GUEST_CR3, save_cr3); 57 GUEST_ASSERT(!vmlaunch()); 58 GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL); 59 60 GUEST_DONE(); 61 } 62 63 static void l1_guest_code(void *data) 64 { 65 if (this_cpu_has(X86_FEATURE_VMX)) 66 l1_vmx_code(data); 67 else 68 l1_svm_code(data); 69 } 70 71 int main(int argc, char *argv[]) 72 { 73 struct kvm_vcpu *vcpu; 74 struct kvm_vm *vm; 75 gva_t guest_gva = 0; 76 77 TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_VMX) || 78 kvm_cpu_has(X86_FEATURE_SVM)); 79 80 vm = vm_create_with_one_vcpu(&vcpu, l1_guest_code); 81 82 if (kvm_cpu_has(X86_FEATURE_VMX)) 83 vcpu_alloc_vmx(vm, &guest_gva); 84 else 85 vcpu_alloc_svm(vm, &guest_gva); 86 87 vcpu_args_set(vcpu, 1, guest_gva); 88 89 for (;;) { 90 struct ucall uc; 91 92 vcpu_run(vcpu); 93 TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_IO); 94 95 switch (get_ucall(vcpu, &uc)) { 96 case UCALL_ABORT: 97 REPORT_GUEST_ASSERT(uc); 98 case UCALL_SYNC: 99 break; 100 case UCALL_DONE: 101 goto done; 102 default: 103 TEST_FAIL("Unknown ucall %lu", uc.cmd); 104 } 105 } 106 107 done: 108 kvm_vm_free(vm); 109 return 0; 110 } 111