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