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1// SPDX-License-Identifier: GPL-2.02/*3 * Copyright (C) 2019, Google LLC.4 *5 * Tests for the IA32_XSS MSR.6 */7#include <sys/ioctl.h>8 9#include "test_util.h"10#include "kvm_util.h"11#include "vmx.h"12 13#define MSR_BITS 6414 15int main(int argc, char *argv[])16{17 bool xss_in_msr_list;18 struct kvm_vm *vm;19 struct kvm_vcpu *vcpu;20 uint64_t xss_val;21 int i, r;22 23 /* Create VM */24 vm = vm_create_with_one_vcpu(&vcpu, NULL);25 26 TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_XSAVES));27 28 xss_val = vcpu_get_msr(vcpu, MSR_IA32_XSS);29 TEST_ASSERT(xss_val == 0,30 "MSR_IA32_XSS should be initialized to zero");31 32 vcpu_set_msr(vcpu, MSR_IA32_XSS, xss_val);33 34 /*35 * At present, KVM only supports a guest IA32_XSS value of 0. Verify36 * that trying to set the guest IA32_XSS to an unsupported value fails.37 * Also, in the future when a non-zero value succeeds check that38 * IA32_XSS is in the list of MSRs to save/restore.39 */40 xss_in_msr_list = kvm_msr_is_in_save_restore_list(MSR_IA32_XSS);41 for (i = 0; i < MSR_BITS; ++i) {42 r = _vcpu_set_msr(vcpu, MSR_IA32_XSS, 1ull << i);43 44 /*45 * Setting a list of MSRs returns the entry that "faulted", or46 * the last entry +1 if all MSRs were successfully written.47 */48 TEST_ASSERT(!r || r == 1, KVM_IOCTL_ERROR(KVM_SET_MSRS, r));49 TEST_ASSERT(r != 1 || xss_in_msr_list,50 "IA32_XSS was able to be set, but was not in save/restore list");51 }52 53 kvm_vm_free(vm);54}55