tools/testing/selftests/kvm/x86_64/smm_test.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2018, Red Hat, Inc.
   4  *
   5  * Tests for SMM.
   6  */
   7 #define _GNU_SOURCE /* for program_invocation_short_name */
   8 #include <fcntl.h>
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11 #include <stdint.h>
  12 #include <string.h>
  13 #include <sys/ioctl.h>
  14
  15 #include "test_util.h"
  16
  17 #include "kvm_util.h"
  18
  19 #include "vmx.h"
  20
  21 #define VCPU_ID       1
  22
  23 #define PAGE_SIZE  4096
  24
  25 #define SMRAM_SIZE 65536
  26 #define SMRAM_MEMSLOT ((1 << 16) | 1)
  27 #define SMRAM_PAGES (SMRAM_SIZE / PAGE_SIZE)
  28 #define SMRAM_GPA 0x1000000
  29 #define SMRAM_STAGE 0xfe
  30
  31 #define STR(x) #x
  32 #define XSTR(s) STR(s)
  33
  34 #define SYNC_PORT 0xe
  35 #define DONE 0xff
  36
  37 /*
  38  * This is compiled as normal 64-bit code, however, SMI handler is executed
  39  * in real-address mode. To stay simple we're limiting ourselves to a mode
  40  * independent subset of asm here.
  41  * SMI handler always report back fixed stage SMRAM_STAGE.
  42  */
  43 uint8_t smi_handler[] = {
  44         0xb0, SMRAM_STAGE,    /* mov $SMRAM_STAGE, %al */
  45         0xe4, SYNC_PORT,      /* in $SYNC_PORT, %al */
  46         0x0f, 0xaa,           /* rsm */
  47 };
  48
  49 void sync_with_host(uint64_t phase)
  50 {
  51         asm volatile("in $" XSTR(SYNC_PORT)", %%al \n"
  52                      : : "a" (phase));
  53 }
  54
  55 void self_smi(void)
  56 {
  57         wrmsr(APIC_BASE_MSR + (APIC_ICR >> 4),
  58               APIC_DEST_SELF | APIC_INT_ASSERT | APIC_DM_SMI);
  59 }
  60
  61 void guest_code(struct vmx_pages *vmx_pages)
  62 {
  63         uint64_t apicbase = rdmsr(MSR_IA32_APICBASE);
  64
  65         sync_with_host(1);
  66
  67         wrmsr(MSR_IA32_APICBASE, apicbase | X2APIC_ENABLE);
  68
  69         sync_with_host(2);
  70
  71         self_smi();
  72
  73         sync_with_host(4);
  74
  75         if (vmx_pages) {
  76                 GUEST_ASSERT(prepare_for_vmx_operation(vmx_pages));
  77
  78                 sync_with_host(5);
  79
  80                 self_smi();
  81
  82                 sync_with_host(7);
  83         }
  84
  85         sync_with_host(DONE);
  86 }
  87
  88 int main(int argc, char *argv[])
  89 {
  90         vm_vaddr_t vmx_pages_gva = 0;
  91
  92         struct kvm_regs regs;
  93         struct kvm_vm *vm;
  94         struct kvm_run *run;
  95         struct kvm_x86_state *state;
  96         int stage, stage_reported;
  97
  98         /* Create VM */
  99         vm = vm_create_default(VCPU_ID, 0, guest_code);
 100
 101         vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid());
 102
 103         run = vcpu_state(vm, VCPU_ID);
 104
 105         vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, SMRAM_GPA,
 106                                     SMRAM_MEMSLOT, SMRAM_PAGES, 0);
 107         TEST_ASSERT(vm_phy_pages_alloc(vm, SMRAM_PAGES, SMRAM_GPA, SMRAM_MEMSLOT)
 108                     == SMRAM_GPA, "could not allocate guest physical addresses?");
 109
 110         memset(addr_gpa2hva(vm, SMRAM_GPA), 0x0, SMRAM_SIZE);
 111         memcpy(addr_gpa2hva(vm, SMRAM_GPA) + 0x8000, smi_handler,
 112                sizeof(smi_handler));
 113
 114         vcpu_set_msr(vm, VCPU_ID, MSR_IA32_SMBASE, SMRAM_GPA);
 115
 116         if (kvm_check_cap(KVM_CAP_NESTED_STATE)) {
 117                 vcpu_alloc_vmx(vm, &vmx_pages_gva);
 118                 vcpu_args_set(vm, VCPU_ID, 1, vmx_pages_gva);
 119         } else {
 120                 printf("will skip SMM test with VMX enabled\n");
 121                 vcpu_args_set(vm, VCPU_ID, 1, 0);
 122         }
 123
 124         for (stage = 1;; stage++) {
 125                 _vcpu_run(vm, VCPU_ID);
 126                 TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
 127                             "Stage %d: unexpected exit reason: %u (%s),\n",
 128                             stage, run->exit_reason,
 129                             exit_reason_str(run->exit_reason));
 130
 131                 memset(&regs, 0, sizeof(regs));
 132                 vcpu_regs_get(vm, VCPU_ID, &regs);
 133
 134                 stage_reported = regs.rax & 0xff;
 135
 136                 if (stage_reported == DONE)
 137                         goto done;
 138
 139                 TEST_ASSERT(stage_reported == stage ||
 140                             stage_reported == SMRAM_STAGE,
 141                             "Unexpected stage: #%x, got %x",
 142                             stage, stage_reported);
 143
 144                 state = vcpu_save_state(vm, VCPU_ID);
 145                 kvm_vm_release(vm);
 146                 kvm_vm_restart(vm, O_RDWR);
 147                 vm_vcpu_add(vm, VCPU_ID);
 148                 vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid());
 149                 vcpu_load_state(vm, VCPU_ID, state);
 150                 run = vcpu_state(vm, VCPU_ID);
 151                 free(state);
 152         }
 153
 154 done:
 155         kvm_vm_free(vm);
 156 }