static __init int svm_hardware_setup(void)
{
	int cpu;
	struct page *iopm_pages;
	void *iopm_va;
	int r;
	unsigned int order = get_order(IOPM_SIZE);

	/*
	 * NX is required for shadow paging and for NPT if the NX huge pages
	 * mitigation is enabled.
	 */
	if (!boot_cpu_has(X86_FEATURE_NX)) {
		pr_err_ratelimited("NX (Execute Disable) not supported\n");
		return -EOPNOTSUPP;
	}
	kvm_enable_efer_bits(EFER_NX);

	iopm_pages = alloc_pages(GFP_KERNEL, order);

	if (!iopm_pages)
		return -ENOMEM;

	iopm_va = page_address(iopm_pages);
	memset(iopm_va, 0xff, PAGE_SIZE * (1 << order));
	iopm_base = page_to_pfn(iopm_pages) << PAGE_SHIFT;

	init_msrpm_offsets();

	supported_xcr0 &= ~(XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR);

	if (boot_cpu_has(X86_FEATURE_FXSR_OPT))
		kvm_enable_efer_bits(EFER_FFXSR);

	if (boot_cpu_has(X86_FEATURE_TSCRATEMSR)) {
		kvm_has_tsc_control = true;
		kvm_max_tsc_scaling_ratio = TSC_RATIO_MAX;
		kvm_tsc_scaling_ratio_frac_bits = 32;
	}

	tsc_aux_uret_slot = kvm_add_user_return_msr(MSR_TSC_AUX);

	/* Check for pause filtering support */
	if (!boot_cpu_has(X86_FEATURE_PAUSEFILTER)) {
		pause_filter_count = 0;
		pause_filter_thresh = 0;
	} else if (!boot_cpu_has(X86_FEATURE_PFTHRESHOLD)) {
		pause_filter_thresh = 0;
	}

	if (nested) {
		printk(KERN_INFO "kvm: Nested Virtualization enabled\n");
		kvm_enable_efer_bits(EFER_SVME | EFER_LMSLE);
	}

	/*
	 * KVM's MMU doesn't support using 2-level paging for itself, and thus
	 * NPT isn't supported if the host is using 2-level paging since host
	 * CR4 is unchanged on VMRUN.
	 */
	if (!IS_ENABLED(CONFIG_X86_64) && !IS_ENABLED(CONFIG_X86_PAE))
		npt_enabled = false;

	if (!boot_cpu_has(X86_FEATURE_NPT))
		npt_enabled = false;

	kvm_configure_mmu(npt_enabled, get_max_npt_level(), PG_LEVEL_1G);
	pr_info("kvm: Nested Paging %sabled\n", npt_enabled ? "en" : "dis");

	/* Note, SEV setup consumes npt_enabled. */
	sev_hardware_setup();

	svm_hv_hardware_setup();

	svm_adjust_mmio_mask();

	for_each_possible_cpu(cpu) {
		r = svm_cpu_init(cpu);
		if (r)
			goto err;
	}

	if (nrips) {
		if (!boot_cpu_has(X86_FEATURE_NRIPS))
			nrips = false;
	}

	enable_apicv = avic = avic && npt_enabled && boot_cpu_has(X86_FEATURE_AVIC);

	if (enable_apicv) {
		pr_info("AVIC enabled\n");

		amd_iommu_register_ga_log_notifier(&avic_ga_log_notifier);
	}

	if (vls) {
		if (!npt_enabled ||
		    !boot_cpu_has(X86_FEATURE_V_VMSAVE_VMLOAD) ||
		    !IS_ENABLED(CONFIG_X86_64)) {
			vls = false;
		} else {
			pr_info("Virtual VMLOAD VMSAVE supported\n");
		}
	}

	if (boot_cpu_has(X86_FEATURE_SVME_ADDR_CHK))
		svm_gp_erratum_intercept = false;

	if (vgif) {
		if (!boot_cpu_has(X86_FEATURE_VGIF))
			vgif = false;
		else
			pr_info("Virtual GIF supported\n");
	}

	svm_set_cpu_caps();

	/*
	 * It seems that on AMD processors PTE's accessed bit is
	 * being set by the CPU hardware before the NPF vmexit.
	 * This is not expected behaviour and our tests fail because
	 * of it.
	 * A workaround here is to disable support for
	 * GUEST_MAXPHYADDR < HOST_MAXPHYADDR if NPT is enabled.
	 * In this case userspace can know if there is support using
	 * KVM_CAP_SMALLER_MAXPHYADDR extension and decide how to handle
	 * it
	 * If future AMD CPU models change the behaviour described above,
	 * this variable can be changed accordingly
	 */
	allow_smaller_maxphyaddr = !npt_enabled;

	return 0;

err:
	svm_hardware_teardown();
	return r;
}
static __init int svm_hardware_setup(void)
{
	int cpu;
	struct page *iopm_pages;
	void *iopm_va;
	int r;
	unsigned int order = get_order(IOPM_SIZE);

	 
	if (!boot_cpu_has(X86_FEATURE_NX)) {
		pr_err_ratelimited("NX (Execute Disable) not supported\n");
		return -EOPNOTSUPP;
	}
	kvm_enable_efer_bits(EFER_NX);

	iopm_pages = alloc_pages(GFP_KERNEL, order);

	if (!iopm_pages)
		return -ENOMEM;

	iopm_va = page_address(iopm_pages);
	memset(iopm_va, 0xff, PAGE_SIZE * (1 << order));
	iopm_base = page_to_pfn(iopm_pages) << PAGE_SHIFT;

	init_msrpm_offsets();

	supported_xcr0 &= ~(XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR);

	if (boot_cpu_has(X86_FEATURE_FXSR_OPT))
		kvm_enable_efer_bits(EFER_FFXSR);

	if (boot_cpu_has(X86_FEATURE_TSCRATEMSR)) {
		kvm_has_tsc_control = true;
		kvm_max_tsc_scaling_ratio = TSC_RATIO_MAX;
		kvm_tsc_scaling_ratio_frac_bits = 32;
	}

	tsc_aux_uret_slot = kvm_add_user_return_msr(MSR_TSC_AUX);

	 
	if (!boot_cpu_has(X86_FEATURE_PAUSEFILTER)) {
		pause_filter_count = 0;
		pause_filter_thresh = 0;
	} else if (!boot_cpu_has(X86_FEATURE_PFTHRESHOLD)) {
		pause_filter_thresh = 0;
	}

	if (nested) {
		printk(KERN_INFO "kvm: Nested Virtualization enabled\n");
		kvm_enable_efer_bits(EFER_SVME | EFER_LMSLE);
	}

	 
	if (!IS_ENABLED(CONFIG_X86_64) && !IS_ENABLED(CONFIG_X86_PAE))
		npt_enabled = false;

	if (!boot_cpu_has(X86_FEATURE_NPT))
		npt_enabled = false;

	kvm_configure_mmu(npt_enabled, get_max_npt_level(), PG_LEVEL_1G);
	pr_info("kvm: Nested Paging %sabled\n", npt_enabled ? "en" : "dis");

	 
	sev_hardware_setup();

	svm_hv_hardware_setup();

	svm_adjust_mmio_mask();

	for_each_possible_cpu(cpu) {
		r = svm_cpu_init(cpu);
		if (r)
			goto err;
	}

	if (nrips) {
		if (!boot_cpu_has(X86_FEATURE_NRIPS))
			nrips = false;
	}

	enable_apicv = avic = avic && npt_enabled && boot_cpu_has(X86_FEATURE_AVIC);

	if (enable_apicv) {
		pr_info("AVIC enabled\n");

		amd_iommu_register_ga_log_notifier(&avic_ga_log_notifier);
	}

	if (vls) {
		if (!npt_enabled ||
		    !boot_cpu_has(X86_FEATURE_V_VMSAVE_VMLOAD) ||
		    !IS_ENABLED(CONFIG_X86_64)) {
			vls = false;
		} else {
			pr_info("Virtual VMLOAD VMSAVE supported\n");
		}
	}

	if (boot_cpu_has(X86_FEATURE_SVME_ADDR_CHK))
		svm_gp_erratum_intercept = false;

	if (vgif) {
		if (!boot_cpu_has(X86_FEATURE_VGIF))
			vgif = false;
		else
			pr_info("Virtual GIF supported\n");
	}

	svm_set_cpu_caps();

	 
	allow_smaller_maxphyaddr = !npt_enabled;

	return 0;

err:
	svm_hardware_teardown();
	return r;
}