1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * KVM_GET/SET_* tests 4 * 5 * Copyright (C) 2022, Red Hat, Inc. 6 * 7 * Tests for Hyper-V extensions to SVM. 8 */ 9 #define _GNU_SOURCE /* for program_invocation_short_name */ 10 #include <fcntl.h> 11 #include <stdio.h> 12 #include <stdlib.h> 13 #include <string.h> 14 #include <sys/ioctl.h> 15 #include <linux/bitmap.h> 16 17 #include "test_util.h" 18 19 #include "kvm_util.h" 20 #include "processor.h" 21 #include "svm_util.h" 22 #include "hyperv.h" 23 24 #define L2_GUEST_STACK_SIZE 256 25 26 struct hv_enlightenments { 27 struct __packed hv_enlightenments_control { 28 u32 nested_flush_hypercall:1; 29 u32 msr_bitmap:1; 30 u32 enlightened_npt_tlb: 1; 31 u32 reserved:29; 32 } __packed hv_enlightenments_control; 33 u32 hv_vp_id; 34 u64 hv_vm_id; 35 u64 partition_assist_page; 36 u64 reserved; 37 } __packed; 38 39 /* 40 * Hyper-V uses the software reserved clean bit in VMCB 41 */ 42 #define VMCB_HV_NESTED_ENLIGHTENMENTS (1U << 31) 43 44 void l2_guest_code(void) 45 { 46 GUEST_SYNC(3); 47 /* Exit to L1 */ 48 vmmcall(); 49 50 /* MSR-Bitmap tests */ 51 rdmsr(MSR_FS_BASE); /* intercepted */ 52 rdmsr(MSR_FS_BASE); /* intercepted */ 53 rdmsr(MSR_GS_BASE); /* not intercepted */ 54 vmmcall(); 55 rdmsr(MSR_GS_BASE); /* intercepted */ 56 57 GUEST_SYNC(5); 58 59 /* Done, exit to L1 and never come back. */ 60 vmmcall(); 61 } 62 63 static void __attribute__((__flatten__)) guest_code(struct svm_test_data *svm) 64 { 65 unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE]; 66 struct vmcb *vmcb = svm->vmcb; 67 struct hv_enlightenments *hve = 68 (struct hv_enlightenments *)vmcb->control.reserved_sw; 69 70 GUEST_SYNC(1); 71 72 wrmsr(HV_X64_MSR_GUEST_OS_ID, (u64)0x8100 << 48); 73 74 GUEST_ASSERT(svm->vmcb_gpa); 75 /* Prepare for L2 execution. */ 76 generic_svm_setup(svm, l2_guest_code, 77 &l2_guest_stack[L2_GUEST_STACK_SIZE]); 78 79 GUEST_SYNC(2); 80 run_guest(vmcb, svm->vmcb_gpa); 81 GUEST_ASSERT(vmcb->control.exit_code == SVM_EXIT_VMMCALL); 82 GUEST_SYNC(4); 83 vmcb->save.rip += 3; 84 85 /* Intercept RDMSR 0xc0000100 */ 86 vmcb->control.intercept |= 1ULL << INTERCEPT_MSR_PROT; 87 set_bit(2 * (MSR_FS_BASE & 0x1fff), svm->msr + 0x800); 88 run_guest(vmcb, svm->vmcb_gpa); 89 GUEST_ASSERT(vmcb->control.exit_code == SVM_EXIT_MSR); 90 vmcb->save.rip += 2; /* rdmsr */ 91 92 /* Enable enlightened MSR bitmap */ 93 hve->hv_enlightenments_control.msr_bitmap = 1; 94 run_guest(vmcb, svm->vmcb_gpa); 95 GUEST_ASSERT(vmcb->control.exit_code == SVM_EXIT_MSR); 96 vmcb->save.rip += 2; /* rdmsr */ 97 98 /* Intercept RDMSR 0xc0000101 without telling KVM about it */ 99 set_bit(2 * (MSR_GS_BASE & 0x1fff), svm->msr + 0x800); 100 /* Make sure HV_VMX_ENLIGHTENED_CLEAN_FIELD_MSR_BITMAP is set */ 101 vmcb->control.clean |= VMCB_HV_NESTED_ENLIGHTENMENTS; 102 run_guest(vmcb, svm->vmcb_gpa); 103 /* Make sure we don't see SVM_EXIT_MSR here so eMSR bitmap works */ 104 GUEST_ASSERT(vmcb->control.exit_code == SVM_EXIT_VMMCALL); 105 vmcb->save.rip += 3; /* vmcall */ 106 107 /* Now tell KVM we've changed MSR-Bitmap */ 108 vmcb->control.clean &= ~VMCB_HV_NESTED_ENLIGHTENMENTS; 109 run_guest(vmcb, svm->vmcb_gpa); 110 GUEST_ASSERT(vmcb->control.exit_code == SVM_EXIT_MSR); 111 vmcb->save.rip += 2; /* rdmsr */ 112 113 run_guest(vmcb, svm->vmcb_gpa); 114 GUEST_ASSERT(vmcb->control.exit_code == SVM_EXIT_VMMCALL); 115 GUEST_SYNC(6); 116 117 GUEST_DONE(); 118 } 119 120 int main(int argc, char *argv[]) 121 { 122 vm_vaddr_t nested_gva = 0; 123 124 struct kvm_vcpu *vcpu; 125 struct kvm_vm *vm; 126 struct kvm_run *run; 127 struct ucall uc; 128 int stage; 129 130 TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_SVM)); 131 132 /* Create VM */ 133 vm = vm_create_with_one_vcpu(&vcpu, guest_code); 134 vcpu_set_hv_cpuid(vcpu); 135 run = vcpu->run; 136 vcpu_alloc_svm(vm, &nested_gva); 137 vcpu_args_set(vcpu, 1, nested_gva); 138 139 for (stage = 1;; stage++) { 140 vcpu_run(vcpu); 141 TEST_ASSERT(run->exit_reason == KVM_EXIT_IO, 142 "Stage %d: unexpected exit reason: %u (%s),\n", 143 stage, run->exit_reason, 144 exit_reason_str(run->exit_reason)); 145 146 switch (get_ucall(vcpu, &uc)) { 147 case UCALL_ABORT: 148 REPORT_GUEST_ASSERT(uc); 149 /* NOT REACHED */ 150 case UCALL_SYNC: 151 break; 152 case UCALL_DONE: 153 goto done; 154 default: 155 TEST_FAIL("Unknown ucall %lu", uc.cmd); 156 } 157 158 /* UCALL_SYNC is handled here. */ 159 TEST_ASSERT(!strcmp((const char *)uc.args[0], "hello") && 160 uc.args[1] == stage, "Stage %d: Unexpected register values vmexit, got %lx", 161 stage, (ulong)uc.args[1]); 162 163 } 164 165 done: 166 kvm_vm_free(vm); 167 } 168