1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * KVM dirty page logging test 4 * 5 * Copyright (C) 2018, Red Hat, Inc. 6 */ 7 8 #define _GNU_SOURCE /* for program_invocation_name */ 9 10 #include <stdio.h> 11 #include <stdlib.h> 12 #include <linux/bitmap.h> 13 #include <linux/bitops.h> 14 15 #include "test_util.h" 16 #include "kvm_util.h" 17 #include "processor.h" 18 #include "vmx.h" 19 20 /* The memory slot index to track dirty pages */ 21 #define TEST_MEM_SLOT_INDEX 1 22 #define TEST_MEM_PAGES 3 23 24 /* L1 guest test virtual memory offset */ 25 #define GUEST_TEST_MEM 0xc0000000 26 27 /* L2 guest test virtual memory offset */ 28 #define NESTED_TEST_MEM1 0xc0001000 29 #define NESTED_TEST_MEM2 0xc0002000 30 31 static void l2_guest_code(void) 32 { 33 *(volatile uint64_t *)NESTED_TEST_MEM1; 34 *(volatile uint64_t *)NESTED_TEST_MEM1 = 1; 35 GUEST_SYNC(true); 36 GUEST_SYNC(false); 37 38 *(volatile uint64_t *)NESTED_TEST_MEM2 = 1; 39 GUEST_SYNC(true); 40 *(volatile uint64_t *)NESTED_TEST_MEM2 = 1; 41 GUEST_SYNC(true); 42 GUEST_SYNC(false); 43 44 /* Exit to L1 and never come back. */ 45 vmcall(); 46 } 47 48 void l1_guest_code(struct vmx_pages *vmx) 49 { 50 #define L2_GUEST_STACK_SIZE 64 51 unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE]; 52 53 GUEST_ASSERT(vmx->vmcs_gpa); 54 GUEST_ASSERT(prepare_for_vmx_operation(vmx)); 55 GUEST_ASSERT(load_vmcs(vmx)); 56 57 prepare_vmcs(vmx, l2_guest_code, 58 &l2_guest_stack[L2_GUEST_STACK_SIZE]); 59 60 GUEST_SYNC(false); 61 GUEST_ASSERT(!vmlaunch()); 62 GUEST_SYNC(false); 63 GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL); 64 GUEST_DONE(); 65 } 66 67 int main(int argc, char *argv[]) 68 { 69 vm_vaddr_t vmx_pages_gva = 0; 70 struct vmx_pages *vmx; 71 unsigned long *bmap; 72 uint64_t *host_test_mem; 73 74 struct kvm_vcpu *vcpu; 75 struct kvm_vm *vm; 76 struct kvm_run *run; 77 struct ucall uc; 78 bool done = false; 79 80 TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_VMX)); 81 82 /* Create VM */ 83 vm = vm_create_with_one_vcpu(&vcpu, l1_guest_code); 84 vmx = vcpu_alloc_vmx(vm, &vmx_pages_gva); 85 vcpu_args_set(vcpu, 1, vmx_pages_gva); 86 run = vcpu->run; 87 88 /* Add an extra memory slot for testing dirty logging */ 89 vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, 90 GUEST_TEST_MEM, 91 TEST_MEM_SLOT_INDEX, 92 TEST_MEM_PAGES, 93 KVM_MEM_LOG_DIRTY_PAGES); 94 95 /* 96 * Add an identity map for GVA range [0xc0000000, 0xc0002000). This 97 * affects both L1 and L2. However... 98 */ 99 virt_map(vm, GUEST_TEST_MEM, GUEST_TEST_MEM, TEST_MEM_PAGES); 100 101 /* 102 * ... pages in the L2 GPA range [0xc0001000, 0xc0003000) will map to 103 * 0xc0000000. 104 * 105 * Note that prepare_eptp should be called only L1's GPA map is done, 106 * meaning after the last call to virt_map. 107 */ 108 prepare_eptp(vmx, vm, 0); 109 nested_map_memslot(vmx, vm, 0); 110 nested_map(vmx, vm, NESTED_TEST_MEM1, GUEST_TEST_MEM, 4096); 111 nested_map(vmx, vm, NESTED_TEST_MEM2, GUEST_TEST_MEM, 4096); 112 113 bmap = bitmap_zalloc(TEST_MEM_PAGES); 114 host_test_mem = addr_gpa2hva(vm, GUEST_TEST_MEM); 115 116 while (!done) { 117 memset(host_test_mem, 0xaa, TEST_MEM_PAGES * 4096); 118 vcpu_run(vcpu); 119 TEST_ASSERT(run->exit_reason == KVM_EXIT_IO, 120 "Unexpected exit reason: %u (%s),\n", 121 run->exit_reason, 122 exit_reason_str(run->exit_reason)); 123 124 switch (get_ucall(vcpu, &uc)) { 125 case UCALL_ABORT: 126 REPORT_GUEST_ASSERT(uc); 127 /* NOT REACHED */ 128 case UCALL_SYNC: 129 /* 130 * The nested guest wrote at offset 0x1000 in the memslot, but the 131 * dirty bitmap must be filled in according to L1 GPA, not L2. 132 */ 133 kvm_vm_get_dirty_log(vm, TEST_MEM_SLOT_INDEX, bmap); 134 if (uc.args[1]) { 135 TEST_ASSERT(test_bit(0, bmap), "Page 0 incorrectly reported clean\n"); 136 TEST_ASSERT(host_test_mem[0] == 1, "Page 0 not written by guest\n"); 137 } else { 138 TEST_ASSERT(!test_bit(0, bmap), "Page 0 incorrectly reported dirty\n"); 139 TEST_ASSERT(host_test_mem[0] == 0xaaaaaaaaaaaaaaaaULL, "Page 0 written by guest\n"); 140 } 141 142 TEST_ASSERT(!test_bit(1, bmap), "Page 1 incorrectly reported dirty\n"); 143 TEST_ASSERT(host_test_mem[4096 / 8] == 0xaaaaaaaaaaaaaaaaULL, "Page 1 written by guest\n"); 144 TEST_ASSERT(!test_bit(2, bmap), "Page 2 incorrectly reported dirty\n"); 145 TEST_ASSERT(host_test_mem[8192 / 8] == 0xaaaaaaaaaaaaaaaaULL, "Page 2 written by guest\n"); 146 break; 147 case UCALL_DONE: 148 done = true; 149 break; 150 default: 151 TEST_FAIL("Unknown ucall %lu", uc.cmd); 152 } 153 } 154 } 155