152d3a4fbSDavid Matlack // SPDX-License-Identifier: GPL-2.0
252d3a4fbSDavid Matlack /*
352d3a4fbSDavid Matlack * Copyright (C) 2020, Google LLC.
452d3a4fbSDavid Matlack *
552d3a4fbSDavid Matlack * Test that KVM emulates instructions in response to EPT violations when
652d3a4fbSDavid Matlack * allow_smaller_maxphyaddr is enabled and guest.MAXPHYADDR < host.MAXPHYADDR.
752d3a4fbSDavid Matlack */
852d3a4fbSDavid Matlack
952d3a4fbSDavid Matlack #define _GNU_SOURCE /* for program_invocation_short_name */
1052d3a4fbSDavid Matlack
1119a2b32fSDavid Matlack #include "flds_emulation.h"
1219a2b32fSDavid Matlack
1352d3a4fbSDavid Matlack #include "test_util.h"
1452d3a4fbSDavid Matlack #include "kvm_util.h"
1552d3a4fbSDavid Matlack #include "vmx.h"
1652d3a4fbSDavid Matlack
1752d3a4fbSDavid Matlack #define MAXPHYADDR 36
1852d3a4fbSDavid Matlack
1952d3a4fbSDavid Matlack #define MEM_REGION_GVA 0x0000123456789000
2052d3a4fbSDavid Matlack #define MEM_REGION_GPA 0x0000000700000000
2152d3a4fbSDavid Matlack #define MEM_REGION_SLOT 10
2252d3a4fbSDavid Matlack #define MEM_REGION_SIZE PAGE_SIZE
2352d3a4fbSDavid Matlack
guest_code(bool tdp_enabled)24*a323845dSDavid Matlack static void guest_code(bool tdp_enabled)
2552d3a4fbSDavid Matlack {
26*a323845dSDavid Matlack uint64_t error_code;
27*a323845dSDavid Matlack uint64_t vector;
28*a323845dSDavid Matlack
29*a323845dSDavid Matlack vector = kvm_asm_safe_ec(FLDS_MEM_EAX, error_code, "a"(MEM_REGION_GVA));
30*a323845dSDavid Matlack
31*a323845dSDavid Matlack /*
32*a323845dSDavid Matlack * When TDP is enabled, flds will trigger an emulation failure, exit to
33*a323845dSDavid Matlack * userspace, and then the selftest host "VMM" skips the instruction.
34*a323845dSDavid Matlack *
35*a323845dSDavid Matlack * When TDP is disabled, no instruction emulation is required so flds
36*a323845dSDavid Matlack * should generate #PF(RSVD).
37*a323845dSDavid Matlack */
38*a323845dSDavid Matlack if (tdp_enabled) {
39*a323845dSDavid Matlack GUEST_ASSERT(!vector);
40*a323845dSDavid Matlack } else {
41*a323845dSDavid Matlack GUEST_ASSERT_EQ(vector, PF_VECTOR);
42*a323845dSDavid Matlack GUEST_ASSERT(error_code & PFERR_RSVD_MASK);
43*a323845dSDavid Matlack }
44*a323845dSDavid Matlack
4552d3a4fbSDavid Matlack GUEST_DONE();
4652d3a4fbSDavid Matlack }
4752d3a4fbSDavid Matlack
main(int argc,char * argv[])4852d3a4fbSDavid Matlack int main(int argc, char *argv[])
4952d3a4fbSDavid Matlack {
5052d3a4fbSDavid Matlack struct kvm_vcpu *vcpu;
5152d3a4fbSDavid Matlack struct kvm_vm *vm;
52*a323845dSDavid Matlack struct ucall uc;
5352d3a4fbSDavid Matlack uint64_t *pte;
5452d3a4fbSDavid Matlack uint64_t *hva;
5552d3a4fbSDavid Matlack uint64_t gpa;
5652d3a4fbSDavid Matlack int rc;
5752d3a4fbSDavid Matlack
5852d3a4fbSDavid Matlack TEST_REQUIRE(kvm_has_cap(KVM_CAP_SMALLER_MAXPHYADDR));
5952d3a4fbSDavid Matlack
6052d3a4fbSDavid Matlack vm = vm_create_with_one_vcpu(&vcpu, guest_code);
61*a323845dSDavid Matlack vcpu_args_set(vcpu, 1, kvm_is_tdp_enabled());
62*a323845dSDavid Matlack
63*a323845dSDavid Matlack vm_init_descriptor_tables(vm);
64*a323845dSDavid Matlack vcpu_init_descriptor_tables(vcpu);
6552d3a4fbSDavid Matlack
6652d3a4fbSDavid Matlack vcpu_set_cpuid_maxphyaddr(vcpu, MAXPHYADDR);
6752d3a4fbSDavid Matlack
6852d3a4fbSDavid Matlack rc = kvm_check_cap(KVM_CAP_EXIT_ON_EMULATION_FAILURE);
6952d3a4fbSDavid Matlack TEST_ASSERT(rc, "KVM_CAP_EXIT_ON_EMULATION_FAILURE is unavailable");
7052d3a4fbSDavid Matlack vm_enable_cap(vm, KVM_CAP_EXIT_ON_EMULATION_FAILURE, 1);
7152d3a4fbSDavid Matlack
7252d3a4fbSDavid Matlack vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS,
7352d3a4fbSDavid Matlack MEM_REGION_GPA, MEM_REGION_SLOT,
7452d3a4fbSDavid Matlack MEM_REGION_SIZE / PAGE_SIZE, 0);
7552d3a4fbSDavid Matlack gpa = vm_phy_pages_alloc(vm, MEM_REGION_SIZE / PAGE_SIZE,
7652d3a4fbSDavid Matlack MEM_REGION_GPA, MEM_REGION_SLOT);
7752d3a4fbSDavid Matlack TEST_ASSERT(gpa == MEM_REGION_GPA, "Failed vm_phy_pages_alloc\n");
7852d3a4fbSDavid Matlack virt_map(vm, MEM_REGION_GVA, MEM_REGION_GPA, 1);
7952d3a4fbSDavid Matlack hva = addr_gpa2hva(vm, MEM_REGION_GPA);
8052d3a4fbSDavid Matlack memset(hva, 0, PAGE_SIZE);
8152d3a4fbSDavid Matlack
8252d3a4fbSDavid Matlack pte = vm_get_page_table_entry(vm, MEM_REGION_GVA);
8352d3a4fbSDavid Matlack *pte |= BIT_ULL(MAXPHYADDR);
8452d3a4fbSDavid Matlack
8552d3a4fbSDavid Matlack vcpu_run(vcpu);
86*a323845dSDavid Matlack
87*a323845dSDavid Matlack /*
88*a323845dSDavid Matlack * When TDP is enabled, KVM must emulate in response the guest physical
89*a323845dSDavid Matlack * address that is illegal from the guest's perspective, but is legal
90*a323845dSDavid Matlack * from hardware's perspeective. This should result in an emulation
91*a323845dSDavid Matlack * failure exit to userspace since KVM doesn't support emulating flds.
92*a323845dSDavid Matlack */
93*a323845dSDavid Matlack if (kvm_is_tdp_enabled()) {
9419a2b32fSDavid Matlack handle_flds_emulation_failure_exit(vcpu);
9552d3a4fbSDavid Matlack vcpu_run(vcpu);
96*a323845dSDavid Matlack }
97*a323845dSDavid Matlack
98*a323845dSDavid Matlack switch (get_ucall(vcpu, &uc)) {
99*a323845dSDavid Matlack case UCALL_ABORT:
100*a323845dSDavid Matlack REPORT_GUEST_ASSERT(uc);
101*a323845dSDavid Matlack break;
102*a323845dSDavid Matlack case UCALL_DONE:
103*a323845dSDavid Matlack break;
104*a323845dSDavid Matlack default:
105*a323845dSDavid Matlack TEST_FAIL("Unrecognized ucall: %lu\n", uc.cmd);
106*a323845dSDavid Matlack }
10752d3a4fbSDavid Matlack
10852d3a4fbSDavid Matlack kvm_vm_free(vm);
10952d3a4fbSDavid Matlack
11052d3a4fbSDavid Matlack return 0;
11152d3a4fbSDavid Matlack }
112