LXR linux/tools/testing/selftests/kvm/x86_64/smm

   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#include "svm_util.h"
  21
  22#define VCPU_ID       1
  23
  24#define PAGE_SIZE  4096
  25
  26#define SMRAM_SIZE 65536
  27#define SMRAM_MEMSLOT ((1 << 16) | 1)
  28#define SMRAM_PAGES (SMRAM_SIZE / PAGE_SIZE)
  29#define SMRAM_GPA 0x1000000
  30#define SMRAM_STAGE 0xfe
  31
  32#define STR(x) #x
  33#define XSTR(s) STR(s)
  34
  35#define SYNC_PORT 0xe
  36#define DONE 0xff
  37
  38/*
  39 * This is compiled as normal 64-bit code, however, SMI handler is executed
  40 * in real-address mode. To stay simple we're limiting ourselves to a mode
  41 * independent subset of asm here.
  42 * SMI handler always report back fixed stage SMRAM_STAGE.
  43 */
  44uint8_t smi_handler[] = {
  45        0xb0, SMRAM_STAGE,    /* mov $SMRAM_STAGE, %al */
  46        0xe4, SYNC_PORT,      /* in $SYNC_PORT, %al */
  47        0x0f, 0xaa,           /* rsm */
  48};
  49
  50static inline void sync_with_host(uint64_t phase)
  51{
  52        asm volatile("in $" XSTR(SYNC_PORT)", %%al \n"
  53                     : "+a" (phase));
  54}
  55
  56void self_smi(void)
  57{
  58        wrmsr(APIC_BASE_MSR + (APIC_ICR >> 4),
  59              APIC_DEST_SELF | APIC_INT_ASSERT | APIC_DM_SMI);
  60}
  61
  62void guest_code(void *arg)
  63{
  64        uint64_t apicbase = rdmsr(MSR_IA32_APICBASE);
  65
  66        sync_with_host(1);
  67
  68        wrmsr(MSR_IA32_APICBASE, apicbase | X2APIC_ENABLE);
  69
  70        sync_with_host(2);
  71
  72        self_smi();
  73
  74        sync_with_host(4);
  75
  76        if (arg) {
  77                if (cpu_has_svm())
  78                        generic_svm_setup(arg, NULL, NULL);
  79                else
  80                        GUEST_ASSERT(prepare_for_vmx_operation(arg));
  81
  82                sync_with_host(5);
  83
  84                self_smi();
  85
  86                sync_with_host(7);
  87        }
  88
  89        sync_with_host(DONE);
  90}
  91
  92int main(int argc, char *argv[])
  93{
  94        vm_vaddr_t nested_gva = 0;
  95
  96        struct kvm_regs regs;
  97        struct kvm_vm *vm;
  98        struct kvm_run *run;
  99        struct kvm_x86_state *state;
 100        int stage, stage_reported;
 101
 102        /* Create VM */
 103        vm = vm_create_default(VCPU_ID, 0, guest_code);
 104
 105        vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid());
 106
 107        run = vcpu_state(vm, VCPU_ID);
 108
 109        vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, SMRAM_GPA,
 110                                    SMRAM_MEMSLOT, SMRAM_PAGES, 0);
 111        TEST_ASSERT(vm_phy_pages_alloc(vm, SMRAM_PAGES, SMRAM_GPA, SMRAM_MEMSLOT)
 112                    == SMRAM_GPA, "could not allocate guest physical addresses?");
 113
 114        memset(addr_gpa2hva(vm, SMRAM_GPA), 0x0, SMRAM_SIZE);
 115        memcpy(addr_gpa2hva(vm, SMRAM_GPA) + 0x8000, smi_handler,
 116               sizeof(smi_handler));
 117
 118        vcpu_set_msr(vm, VCPU_ID, MSR_IA32_SMBASE, SMRAM_GPA);
 119
 120        if (kvm_check_cap(KVM_CAP_NESTED_STATE)) {
 121                if (nested_svm_supported())
 122                        vcpu_alloc_svm(vm, &nested_gva);
 123                else if (nested_vmx_supported())
 124                        vcpu_alloc_vmx(vm, &nested_gva);
 125        }
 126
 127        if (!nested_gva)
 128                pr_info("will skip SMM test with VMX enabled\n");
 129
 130        vcpu_args_set(vm, VCPU_ID, 1, nested_gva);
 131
 132        for (stage = 1;; stage++) {
 133                _vcpu_run(vm, VCPU_ID);
 134                TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
 135                            "Stage %d: unexpected exit reason: %u (%s),\n",
 136                            stage, run->exit_reason,
 137                            exit_reason_str(run->exit_reason));
 138
 139                memset(&regs, 0, sizeof(regs));
 140                vcpu_regs_get(vm, VCPU_ID, &regs);
 141
 142                stage_reported = regs.rax & 0xff;
 143
 144                if (stage_reported == DONE)
 145                        goto done;
 146
 147                TEST_ASSERT(stage_reported == stage ||
 148                            stage_reported == SMRAM_STAGE,
 149                            "Unexpected stage: #%x, got %x",
 150                            stage, stage_reported);
 151
 152                state = vcpu_save_state(vm, VCPU_ID);
 153                kvm_vm_release(vm);
 154                kvm_vm_restart(vm, O_RDWR);
 155                vm_vcpu_add(vm, VCPU_ID);
 156                vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid());
 157                vcpu_load_state(vm, VCPU_ID, state);
 158                run = vcpu_state(vm, VCPU_ID);
 159                free(state);
 160        }
 161
 162done:
 163        kvm_vm_free(vm);
 164}
 165