diff options
| -rw-r--r-- | tools/testing/selftests/kvm/.gitignore | 1 | ||||
| -rw-r--r-- | tools/testing/selftests/kvm/Makefile | 1 | ||||
| -rw-r--r-- | tools/testing/selftests/kvm/x86_64/fix_hypercall_test.c | 170 |
3 files changed, 172 insertions, 0 deletions
diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore index 9b67343dc4ab..1f1b6c978bf7 100644 --- a/tools/testing/selftests/kvm/.gitignore +++ b/tools/testing/selftests/kvm/.gitignore @@ -15,6 +15,7 @@ /x86_64/debug_regs /x86_64/evmcs_test /x86_64/emulator_error_test +/x86_64/fix_hypercall_test /x86_64/get_msr_index_features /x86_64/kvm_clock_test /x86_64/kvm_pv_test diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile index 04099f453b59..03662666b30d 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -48,6 +48,7 @@ TEST_GEN_PROGS_x86_64 += x86_64/cr4_cpuid_sync_test TEST_GEN_PROGS_x86_64 += x86_64/get_msr_index_features TEST_GEN_PROGS_x86_64 += x86_64/evmcs_test TEST_GEN_PROGS_x86_64 += x86_64/emulator_error_test +TEST_GEN_PROGS_x86_64 += x86_64/fix_hypercall_test TEST_GEN_PROGS_x86_64 += x86_64/hyperv_clock TEST_GEN_PROGS_x86_64 += x86_64/hyperv_cpuid TEST_GEN_PROGS_x86_64 += x86_64/hyperv_features diff --git a/tools/testing/selftests/kvm/x86_64/fix_hypercall_test.c b/tools/testing/selftests/kvm/x86_64/fix_hypercall_test.c new file mode 100644 index 000000000000..1f5c32146f3d --- /dev/null +++ b/tools/testing/selftests/kvm/x86_64/fix_hypercall_test.c @@ -0,0 +1,170 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2020, Google LLC. + * + * Tests for KVM paravirtual feature disablement + */ +#include <asm/kvm_para.h> +#include <linux/kvm_para.h> +#include <linux/stringify.h> +#include <stdint.h> + +#include "apic.h" +#include "test_util.h" +#include "kvm_util.h" +#include "processor.h" + +#define VCPU_ID 0 + +static bool ud_expected; + +static void guest_ud_handler(struct ex_regs *regs) +{ + GUEST_ASSERT(ud_expected); + GUEST_DONE(); +} + +extern unsigned char svm_hypercall_insn; +static uint64_t svm_do_sched_yield(uint8_t apic_id) +{ + uint64_t ret; + + asm volatile("mov %1, %%rax\n\t" + "mov %2, %%rbx\n\t" + "svm_hypercall_insn:\n\t" + "vmmcall\n\t" + "mov %%rax, %0\n\t" + : "=r"(ret) + : "r"((uint64_t)KVM_HC_SCHED_YIELD), "r"((uint64_t)apic_id) + : "rax", "rbx", "memory"); + + return ret; +} + +extern unsigned char vmx_hypercall_insn; +static uint64_t vmx_do_sched_yield(uint8_t apic_id) +{ + uint64_t ret; + + asm volatile("mov %1, %%rax\n\t" + "mov %2, %%rbx\n\t" + "vmx_hypercall_insn:\n\t" + "vmcall\n\t" + "mov %%rax, %0\n\t" + : "=r"(ret) + : "r"((uint64_t)KVM_HC_SCHED_YIELD), "r"((uint64_t)apic_id) + : "rax", "rbx", "memory"); + + return ret; +} + +static void assert_hypercall_insn(unsigned char *exp_insn, unsigned char *obs_insn) +{ + uint32_t exp = 0, obs = 0; + + memcpy(&exp, exp_insn, sizeof(exp)); + memcpy(&obs, obs_insn, sizeof(obs)); + + GUEST_ASSERT_EQ(exp, obs); +} + +static void guest_main(void) +{ + unsigned char *native_hypercall_insn, *hypercall_insn; + uint8_t apic_id; + + apic_id = GET_APIC_ID_FIELD(xapic_read_reg(APIC_ID)); + + if (is_intel_cpu()) { + native_hypercall_insn = &vmx_hypercall_insn; + hypercall_insn = &svm_hypercall_insn; + svm_do_sched_yield(apic_id); + } else if (is_amd_cpu()) { + native_hypercall_insn = &svm_hypercall_insn; + hypercall_insn = &vmx_hypercall_insn; + vmx_do_sched_yield(apic_id); + } else { + GUEST_ASSERT(0); + /* unreachable */ + return; + } + + GUEST_ASSERT(!ud_expected); + assert_hypercall_insn(native_hypercall_insn, hypercall_insn); + GUEST_DONE(); +} + +static void setup_ud_vector(struct kvm_vm *vm) +{ + vm_init_descriptor_tables(vm); + vcpu_init_descriptor_tables(vm, VCPU_ID); + vm_install_exception_handler(vm, UD_VECTOR, guest_ud_handler); +} + +static void enter_guest(struct kvm_vm *vm) +{ + struct kvm_run *run; + struct ucall uc; + + run = vcpu_state(vm, VCPU_ID); + + vcpu_run(vm, VCPU_ID); + switch (get_ucall(vm, VCPU_ID, &uc)) { + case UCALL_SYNC: + pr_info("%s: %016lx\n", (const char *)uc.args[2], uc.args[3]); + break; + case UCALL_DONE: + return; + case UCALL_ABORT: + TEST_FAIL("%s at %s:%ld", (const char *)uc.args[0], __FILE__, uc.args[1]); + default: + TEST_FAIL("Unhandled ucall: %ld\nexit_reason: %u (%s)", + uc.cmd, run->exit_reason, exit_reason_str(run->exit_reason)); + } +} + +static void test_fix_hypercall(void) +{ + struct kvm_vm *vm; + + vm = vm_create_default(VCPU_ID, 0, guest_main); + setup_ud_vector(vm); + + ud_expected = false; + sync_global_to_guest(vm, ud_expected); + + virt_pg_map(vm, APIC_DEFAULT_GPA, APIC_DEFAULT_GPA); + + enter_guest(vm); +} + +static void test_fix_hypercall_disabled(void) +{ + struct kvm_enable_cap cap = {0}; + struct kvm_vm *vm; + + vm = vm_create_default(VCPU_ID, 0, guest_main); + setup_ud_vector(vm); + + cap.cap = KVM_CAP_DISABLE_QUIRKS2; + cap.args[0] = KVM_X86_QUIRK_FIX_HYPERCALL_INSN; + vm_enable_cap(vm, &cap); + + ud_expected = true; + sync_global_to_guest(vm, ud_expected); + + virt_pg_map(vm, APIC_DEFAULT_GPA, APIC_DEFAULT_GPA); + + enter_guest(vm); +} + +int main(void) +{ + if (!(kvm_check_cap(KVM_CAP_DISABLE_QUIRKS2) & KVM_X86_QUIRK_FIX_HYPERCALL_INSN)) { + print_skip("KVM_X86_QUIRK_HYPERCALL_INSN not supported"); + exit(KSFT_SKIP); + } + + test_fix_hypercall(); + test_fix_hypercall_disabled(); +} |