| // SPDX-License-Identifier: GPL-2.0 |
| #include <fcntl.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <sys/ioctl.h> |
| |
| #include "kvm_util.h" |
| #include "processor.h" |
| |
| #define CPUID_MWAIT (1u << 3) |
| |
| enum monitor_mwait_testcases { |
| MWAIT_QUIRK_DISABLED = BIT(0), |
| MISC_ENABLES_QUIRK_DISABLED = BIT(1), |
| MWAIT_DISABLED = BIT(2), |
| }; |
| |
| static void guest_monitor_wait(int testcase) |
| { |
| /* |
| * If both MWAIT and its quirk are disabled, MONITOR/MWAIT should #UD, |
| * in all other scenarios KVM should emulate them as nops. |
| */ |
| bool fault_wanted = (testcase & MWAIT_QUIRK_DISABLED) && |
| (testcase & MWAIT_DISABLED); |
| u8 vector; |
| |
| GUEST_SYNC(testcase); |
| |
| /* |
| * Arbitrarily MONITOR this function, SVM performs fault checks before |
| * intercept checks, so the inputs for MONITOR and MWAIT must be valid. |
| */ |
| vector = kvm_asm_safe("monitor", "a"(guest_monitor_wait), "c"(0), "d"(0)); |
| if (fault_wanted) |
| GUEST_ASSERT_2(vector == UD_VECTOR, testcase, vector); |
| else |
| GUEST_ASSERT_2(!vector, testcase, vector); |
| |
| vector = kvm_asm_safe("mwait", "a"(guest_monitor_wait), "c"(0), "d"(0)); |
| if (fault_wanted) |
| GUEST_ASSERT_2(vector == UD_VECTOR, testcase, vector); |
| else |
| GUEST_ASSERT_2(!vector, testcase, vector); |
| } |
| |
| static void guest_code(void) |
| { |
| guest_monitor_wait(MWAIT_DISABLED); |
| |
| guest_monitor_wait(MWAIT_QUIRK_DISABLED | MWAIT_DISABLED); |
| |
| guest_monitor_wait(MISC_ENABLES_QUIRK_DISABLED | MWAIT_DISABLED); |
| guest_monitor_wait(MISC_ENABLES_QUIRK_DISABLED); |
| |
| guest_monitor_wait(MISC_ENABLES_QUIRK_DISABLED | MWAIT_QUIRK_DISABLED | MWAIT_DISABLED); |
| guest_monitor_wait(MISC_ENABLES_QUIRK_DISABLED | MWAIT_QUIRK_DISABLED); |
| |
| GUEST_DONE(); |
| } |
| |
| int main(int argc, char *argv[]) |
| { |
| uint64_t disabled_quirks; |
| struct kvm_vcpu *vcpu; |
| struct kvm_run *run; |
| struct kvm_vm *vm; |
| struct ucall uc; |
| int testcase; |
| |
| TEST_REQUIRE(kvm_has_cap(KVM_CAP_DISABLE_QUIRKS2)); |
| |
| vm = vm_create_with_one_vcpu(&vcpu, guest_code); |
| vcpu_clear_cpuid_feature(vcpu, X86_FEATURE_MWAIT); |
| |
| run = vcpu->run; |
| |
| vm_init_descriptor_tables(vm); |
| vcpu_init_descriptor_tables(vcpu); |
| |
| while (1) { |
| vcpu_run(vcpu); |
| |
| TEST_ASSERT(run->exit_reason == KVM_EXIT_IO, |
| "Unexpected exit reason: %u (%s),\n", |
| run->exit_reason, |
| exit_reason_str(run->exit_reason)); |
| |
| switch (get_ucall(vcpu, &uc)) { |
| case UCALL_SYNC: |
| testcase = uc.args[1]; |
| break; |
| case UCALL_ABORT: |
| REPORT_GUEST_ASSERT_2(uc, "testcase = %lx, vector = %ld"); |
| goto done; |
| case UCALL_DONE: |
| goto done; |
| default: |
| TEST_FAIL("Unknown ucall %lu", uc.cmd); |
| goto done; |
| } |
| |
| disabled_quirks = 0; |
| if (testcase & MWAIT_QUIRK_DISABLED) |
| disabled_quirks |= KVM_X86_QUIRK_MWAIT_NEVER_UD_FAULTS; |
| if (testcase & MISC_ENABLES_QUIRK_DISABLED) |
| disabled_quirks |= KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT; |
| vm_enable_cap(vm, KVM_CAP_DISABLE_QUIRKS2, disabled_quirks); |
| |
| /* |
| * If the MISC_ENABLES quirk (KVM neglects to update CPUID to |
| * enable/disable MWAIT) is disabled, toggle the ENABLE_MWAIT |
| * bit in MISC_ENABLES accordingly. If the quirk is enabled, |
| * the only valid configuration is MWAIT disabled, as CPUID |
| * can't be manually changed after running the vCPU. |
| */ |
| if (!(testcase & MISC_ENABLES_QUIRK_DISABLED)) { |
| TEST_ASSERT(testcase & MWAIT_DISABLED, |
| "Can't toggle CPUID features after running vCPU"); |
| continue; |
| } |
| |
| vcpu_set_msr(vcpu, MSR_IA32_MISC_ENABLE, |
| (testcase & MWAIT_DISABLED) ? 0 : MSR_IA32_MISC_ENABLE_MWAIT); |
| } |
| |
| done: |
| kvm_vm_free(vm); |
| return 0; |
| } |