1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * xen_vmcall_test 4 * 5 * Copyright © 2020 Amazon.com, Inc. or its affiliates. 6 * 7 * Userspace hypercall testing 8 */ 9 10 #include "test_util.h" 11 #include "kvm_util.h" 12 #include "processor.h" 13 14 #define VCPU_ID 5 15 16 #define HCALL_REGION_GPA 0xc0000000ULL 17 #define HCALL_REGION_SLOT 10 18 #define PAGE_SIZE 4096 19 20 static struct kvm_vm *vm; 21 22 #define INPUTVALUE 17 23 #define ARGVALUE(x) (0xdeadbeef5a5a0000UL + x) 24 #define RETVALUE 0xcafef00dfbfbffffUL 25 26 #define XEN_HYPERCALL_MSR 0x40000200 27 #define HV_GUEST_OS_ID_MSR 0x40000000 28 #define HV_HYPERCALL_MSR 0x40000001 29 30 #define HVCALL_SIGNAL_EVENT 0x005d 31 #define HV_STATUS_INVALID_ALIGNMENT 4 32 33 static void guest_code(void) 34 { 35 unsigned long rax = INPUTVALUE; 36 unsigned long rdi = ARGVALUE(1); 37 unsigned long rsi = ARGVALUE(2); 38 unsigned long rdx = ARGVALUE(3); 39 unsigned long rcx; 40 register unsigned long r10 __asm__("r10") = ARGVALUE(4); 41 register unsigned long r8 __asm__("r8") = ARGVALUE(5); 42 register unsigned long r9 __asm__("r9") = ARGVALUE(6); 43 44 /* First a direct invocation of 'vmcall' */ 45 __asm__ __volatile__("vmcall" : 46 "=a"(rax) : 47 "a"(rax), "D"(rdi), "S"(rsi), "d"(rdx), 48 "r"(r10), "r"(r8), "r"(r9)); 49 GUEST_ASSERT(rax == RETVALUE); 50 51 /* Fill in the Xen hypercall page */ 52 __asm__ __volatile__("wrmsr" : : "c" (XEN_HYPERCALL_MSR), 53 "a" (HCALL_REGION_GPA & 0xffffffff), 54 "d" (HCALL_REGION_GPA >> 32)); 55 56 /* Set Hyper-V Guest OS ID */ 57 __asm__ __volatile__("wrmsr" : : "c" (HV_GUEST_OS_ID_MSR), 58 "a" (0x5a), "d" (0)); 59 60 /* Hyper-V hypercall page */ 61 u64 msrval = HCALL_REGION_GPA + PAGE_SIZE + 1; 62 __asm__ __volatile__("wrmsr" : : "c" (HV_HYPERCALL_MSR), 63 "a" (msrval & 0xffffffff), 64 "d" (msrval >> 32)); 65 66 /* Invoke a Xen hypercall */ 67 __asm__ __volatile__("call *%1" : "=a"(rax) : 68 "r"(HCALL_REGION_GPA + INPUTVALUE * 32), 69 "a"(rax), "D"(rdi), "S"(rsi), "d"(rdx), 70 "r"(r10), "r"(r8), "r"(r9)); 71 GUEST_ASSERT(rax == RETVALUE); 72 73 /* Invoke a Hyper-V hypercall */ 74 rax = 0; 75 rcx = HVCALL_SIGNAL_EVENT; /* code */ 76 rdx = 0x5a5a5a5a; /* ingpa (badly aligned) */ 77 __asm__ __volatile__("call *%1" : "=a"(rax) : 78 "r"(HCALL_REGION_GPA + PAGE_SIZE), 79 "a"(rax), "c"(rcx), "d"(rdx), 80 "r"(r8)); 81 GUEST_ASSERT(rax == HV_STATUS_INVALID_ALIGNMENT); 82 83 GUEST_DONE(); 84 } 85 86 int main(int argc, char *argv[]) 87 { 88 if (!(kvm_check_cap(KVM_CAP_XEN_HVM) & 89 KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL) ) { 90 print_skip("KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL not available"); 91 exit(KSFT_SKIP); 92 } 93 94 vm = vm_create_default(VCPU_ID, 0, (void *) guest_code); 95 vcpu_set_hv_cpuid(vm, VCPU_ID); 96 97 struct kvm_xen_hvm_config hvmc = { 98 .flags = KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL, 99 .msr = XEN_HYPERCALL_MSR, 100 }; 101 vm_ioctl(vm, KVM_XEN_HVM_CONFIG, &hvmc); 102 103 /* Map a region for the hypercall pages */ 104 vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, 105 HCALL_REGION_GPA, HCALL_REGION_SLOT, 2, 0); 106 virt_map(vm, HCALL_REGION_GPA, HCALL_REGION_GPA, 2, 0); 107 108 for (;;) { 109 volatile struct kvm_run *run = vcpu_state(vm, VCPU_ID); 110 struct ucall uc; 111 112 vcpu_run(vm, VCPU_ID); 113 114 if (run->exit_reason == KVM_EXIT_XEN) { 115 ASSERT_EQ(run->xen.type, KVM_EXIT_XEN_HCALL); 116 ASSERT_EQ(run->xen.u.hcall.cpl, 0); 117 ASSERT_EQ(run->xen.u.hcall.longmode, 1); 118 ASSERT_EQ(run->xen.u.hcall.input, INPUTVALUE); 119 ASSERT_EQ(run->xen.u.hcall.params[0], ARGVALUE(1)); 120 ASSERT_EQ(run->xen.u.hcall.params[1], ARGVALUE(2)); 121 ASSERT_EQ(run->xen.u.hcall.params[2], ARGVALUE(3)); 122 ASSERT_EQ(run->xen.u.hcall.params[3], ARGVALUE(4)); 123 ASSERT_EQ(run->xen.u.hcall.params[4], ARGVALUE(5)); 124 ASSERT_EQ(run->xen.u.hcall.params[5], ARGVALUE(6)); 125 run->xen.u.hcall.result = RETVALUE; 126 continue; 127 } 128 129 TEST_ASSERT(run->exit_reason == KVM_EXIT_IO, 130 "Got exit_reason other than KVM_EXIT_IO: %u (%s)\n", 131 run->exit_reason, 132 exit_reason_str(run->exit_reason)); 133 134 switch (get_ucall(vm, VCPU_ID, &uc)) { 135 case UCALL_ABORT: 136 TEST_FAIL("%s", (const char *)uc.args[0]); 137 /* NOT REACHED */ 138 case UCALL_SYNC: 139 break; 140 case UCALL_DONE: 141 goto done; 142 default: 143 TEST_FAIL("Unknown ucall 0x%lx.", uc.cmd); 144 } 145 } 146 done: 147 kvm_vm_free(vm); 148 return 0; 149 } 150