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 #define VCPU_ID 1 21 22 /* The memory slot index to track dirty pages */ 23 #define TEST_MEM_SLOT_INDEX 1 24 #define TEST_MEM_PAGES 3 25 26 /* L1 guest test virtual memory offset */ 27 #define GUEST_TEST_MEM 0xc0000000 28 29 /* L2 guest test virtual memory offset */ 30 #define NESTED_TEST_MEM1 0xc0001000 31 #define NESTED_TEST_MEM2 0xc0002000 32 33 static void l2_guest_code(void) 34 { 35 *(volatile uint64_t *)NESTED_TEST_MEM1; 36 *(volatile uint64_t *)NESTED_TEST_MEM1 = 1; 37 GUEST_SYNC(true); 38 GUEST_SYNC(false); 39 40 *(volatile uint64_t *)NESTED_TEST_MEM2 = 1; 41 GUEST_SYNC(true); 42 *(volatile uint64_t *)NESTED_TEST_MEM2 = 1; 43 GUEST_SYNC(true); 44 GUEST_SYNC(false); 45 46 /* Exit to L1 and never come back. */ 47 vmcall(); 48 } 49 50 void l1_guest_code(struct vmx_pages *vmx) 51 { 52 #define L2_GUEST_STACK_SIZE 64 53 unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE]; 54 55 GUEST_ASSERT(vmx->vmcs_gpa); 56 GUEST_ASSERT(prepare_for_vmx_operation(vmx)); 57 GUEST_ASSERT(load_vmcs(vmx)); 58 59 prepare_vmcs(vmx, l2_guest_code, 60 &l2_guest_stack[L2_GUEST_STACK_SIZE]); 61 62 GUEST_SYNC(false); 63 GUEST_ASSERT(!vmlaunch()); 64 GUEST_SYNC(false); 65 GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL); 66 GUEST_DONE(); 67 } 68 69 int main(int argc, char *argv[]) 70 { 71 vm_vaddr_t vmx_pages_gva = 0; 72 struct vmx_pages *vmx; 73 unsigned long *bmap; 74 uint64_t *host_test_mem; 75 76 struct kvm_vm *vm; 77 struct kvm_run *run; 78 struct ucall uc; 79 bool done = false; 80 81 nested_vmx_check_supported(); 82 83 /* Create VM */ 84 vm = vm_create_default(VCPU_ID, 0, l1_guest_code); 85 vmx = vcpu_alloc_vmx(vm, &vmx_pages_gva); 86 vcpu_args_set(vm, VCPU_ID, 1, vmx_pages_gva); 87 run = vcpu_state(vm, VCPU_ID); 88 89 /* Add an extra memory slot for testing dirty logging */ 90 vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, 91 GUEST_TEST_MEM, 92 TEST_MEM_SLOT_INDEX, 93 TEST_MEM_PAGES, 94 KVM_MEM_LOG_DIRTY_PAGES); 95 96 /* 97 * Add an identity map for GVA range [0xc0000000, 0xc0002000). This 98 * affects both L1 and L2. However... 99 */ 100 virt_map(vm, GUEST_TEST_MEM, GUEST_TEST_MEM, TEST_MEM_PAGES); 101 102 /* 103 * ... pages in the L2 GPA range [0xc0001000, 0xc0003000) will map to 104 * 0xc0000000. 105 * 106 * Note that prepare_eptp should be called only L1's GPA map is done, 107 * meaning after the last call to virt_map. 108 */ 109 prepare_eptp(vmx, vm, 0); 110 nested_map_memslot(vmx, vm, 0); 111 nested_map(vmx, vm, NESTED_TEST_MEM1, GUEST_TEST_MEM, 4096); 112 nested_map(vmx, vm, NESTED_TEST_MEM2, GUEST_TEST_MEM, 4096); 113 114 bmap = bitmap_zalloc(TEST_MEM_PAGES); 115 host_test_mem = addr_gpa2hva(vm, GUEST_TEST_MEM); 116 117 while (!done) { 118 memset(host_test_mem, 0xaa, TEST_MEM_PAGES * 4096); 119 _vcpu_run(vm, VCPU_ID); 120 TEST_ASSERT(run->exit_reason == KVM_EXIT_IO, 121 "Unexpected exit reason: %u (%s),\n", 122 run->exit_reason, 123 exit_reason_str(run->exit_reason)); 124 125 switch (get_ucall(vm, VCPU_ID, &uc)) { 126 case UCALL_ABORT: 127 TEST_FAIL("%s at %s:%ld", (const char *)uc.args[0], 128 __FILE__, uc.args[1]); 129 /* NOT REACHED */ 130 case UCALL_SYNC: 131 /* 132 * The nested guest wrote at offset 0x1000 in the memslot, but the 133 * dirty bitmap must be filled in according to L1 GPA, not L2. 134 */ 135 kvm_vm_get_dirty_log(vm, TEST_MEM_SLOT_INDEX, bmap); 136 if (uc.args[1]) { 137 TEST_ASSERT(test_bit(0, bmap), "Page 0 incorrectly reported clean\n"); 138 TEST_ASSERT(host_test_mem[0] == 1, "Page 0 not written by guest\n"); 139 } else { 140 TEST_ASSERT(!test_bit(0, bmap), "Page 0 incorrectly reported dirty\n"); 141 TEST_ASSERT(host_test_mem[0] == 0xaaaaaaaaaaaaaaaaULL, "Page 0 written by guest\n"); 142 } 143 144 TEST_ASSERT(!test_bit(1, bmap), "Page 1 incorrectly reported dirty\n"); 145 TEST_ASSERT(host_test_mem[4096 / 8] == 0xaaaaaaaaaaaaaaaaULL, "Page 1 written by guest\n"); 146 TEST_ASSERT(!test_bit(2, bmap), "Page 2 incorrectly reported dirty\n"); 147 TEST_ASSERT(host_test_mem[8192 / 8] == 0xaaaaaaaaaaaaaaaaULL, "Page 2 written by guest\n"); 148 break; 149 case UCALL_DONE: 150 done = true; 151 break; 152 default: 153 TEST_FAIL("Unknown ucall %lu", uc.cmd); 154 } 155 } 156 } 157