// SPDX-License-Identifier: GPL-2.0-only
/*
 * Kernel-based Virtual Machine driver for Linux
 *
 * This module enables machines with Intel VT-x extensions to run virtual
 * machines without emulation or binary translation.
 *
 * Copyright (C) 2006 Qumranet, Inc.
 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
 *
 * Authors:
 *   Avi Kivity   <avi@qumranet.com>
 *   Yaniv Kamay  <yaniv@qumranet.com>
 */
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/highmem.h>
#include <linux/hrtimer.h>
#include <linux/kernel.h>
#include <linux/kvm_host.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/mod_devicetable.h>
#include <linux/mm.h>
#include <linux/objtool.h>
#include <linux/sched.h>
#include <linux/sched/smt.h>
#include <linux/slab.h>
#include <linux/tboot.h>
#include <linux/trace_events.h>
#include <linux/entry-kvm.h>

#include <asm/apic.h>
#include <asm/asm.h>
#include <asm/cpu.h>
#include <asm/cpu_device_id.h>
#include <asm/debugreg.h>
#include <asm/desc.h>
#include <asm/fpu/api.h>
#include <asm/fpu/xstate.h>
#include <asm/idtentry.h>
#include <asm/io.h>
#include <asm/irq_remapping.h>
#include <asm/reboot.h>
#include <asm/perf_event.h>
#include <asm/mmu_context.h>
#include <asm/mshyperv.h>
#include <asm/mwait.h>
#include <asm/spec-ctrl.h>
#include <asm/vmx.h>

#include "capabilities.h"
#include "cpuid.h"
#include "hyperv.h"
#include "kvm_onhyperv.h"
#include "irq.h"
#include "kvm_cache_regs.h"
#include "lapic.h"
#include "mmu.h"
#include "nested.h"
#include "pmu.h"
#include "sgx.h"
#include "trace.h"
#include "vmcs.h"
#include "vmcs12.h"
#include "vmx.h"
#include "x86.h"
#include "smm.h"

MODULE_AUTHOR("Qumranet");
MODULE_LICENSE("GPL");

#ifdef MODULE
static const struct x86_cpu_id vmx_cpu_id[] = {
	X86_MATCH_FEATURE(X86_FEATURE_VMX, NULL),
	{}
};
MODULE_DEVICE_TABLE(x86cpu, vmx_cpu_id);
#endif

bool __read_mostly enable_vpid = 1;
module_param_named(vpid, enable_vpid, bool, 0444);

static bool __read_mostly enable_vnmi = 1;
module_param_named(vnmi, enable_vnmi, bool, S_IRUGO);

bool __read_mostly flexpriority_enabled = 1;
module_param_named(flexpriority, flexpriority_enabled, bool, S_IRUGO);

bool __read_mostly enable_ept = 1;
module_param_named(ept, enable_ept, bool, S_IRUGO);

bool __read_mostly enable_unrestricted_guest = 1;
module_param_named(unrestricted_guest,
			enable_unrestricted_guest, bool, S_IRUGO);

bool __read_mostly enable_ept_ad_bits = 1;
module_param_named(eptad, enable_ept_ad_bits, bool, S_IRUGO);

static bool __read_mostly emulate_invalid_guest_state = true;
module_param(emulate_invalid_guest_state, bool, S_IRUGO);

static bool __read_mostly fasteoi = 1;
module_param(fasteoi, bool, S_IRUGO);

module_param(enable_apicv, bool, S_IRUGO);

bool __read_mostly enable_ipiv = true;
module_param(enable_ipiv, bool, 0444);

/*
 * If nested=1, nested virtualization is supported, i.e., guests may use
 * VMX and be a hypervisor for its own guests. If nested=0, guests may not
 * use VMX instructions.
 */
static bool __read_mostly nested = 1;
module_param(nested, bool, S_IRUGO);

bool __read_mostly enable_pml = 1;
module_param_named(pml, enable_pml, bool, S_IRUGO);

static bool __read_mostly error_on_inconsistent_vmcs_config = true;
module_param(error_on_inconsistent_vmcs_config, bool, 0444);

static bool __read_mostly dump_invalid_vmcs = 0;
module_param(dump_invalid_vmcs, bool, 0644);

#define MSR_BITMAP_MODE_X2APIC		1
#define MSR_BITMAP_MODE_X2APIC_APICV	2

#define KVM_VMX_TSC_MULTIPLIER_MAX     0xffffffffffffffffULL

/* Guest_tsc -> host_tsc conversion requires 64-bit division.  */
static int __read_mostly cpu_preemption_timer_multi;
static bool __read_mostly enable_preemption_timer = 1;
#ifdef CONFIG_X86_64
module_param_named(preemption_timer, enable_preemption_timer, bool, S_IRUGO);
#endif

extern bool __read_mostly allow_smaller_maxphyaddr;
module_param(allow_smaller_maxphyaddr, bool, S_IRUGO);

#define KVM_VM_CR0_ALWAYS_OFF (X86_CR0_NW | X86_CR0_CD)
#define KVM_VM_CR0_ALWAYS_ON_UNRESTRICTED_GUEST X86_CR0_NE
#define KVM_VM_CR0_ALWAYS_ON				\
	(KVM_VM_CR0_ALWAYS_ON_UNRESTRICTED_GUEST | X86_CR0_PG | X86_CR0_PE)

#define KVM_VM_CR4_ALWAYS_ON_UNRESTRICTED_GUEST X86_CR4_VMXE
#define KVM_PMODE_VM_CR4_ALWAYS_ON (X86_CR4_PAE | X86_CR4_VMXE)
#define KVM_RMODE_VM_CR4_ALWAYS_ON (X86_CR4_VME | X86_CR4_PAE | X86_CR4_VMXE)

#define RMODE_GUEST_OWNED_EFLAGS_BITS (~(X86_EFLAGS_IOPL | X86_EFLAGS_VM))

#define MSR_IA32_RTIT_STATUS_MASK (~(RTIT_STATUS_FILTEREN | \
	RTIT_STATUS_CONTEXTEN | RTIT_STATUS_TRIGGEREN | \
	RTIT_STATUS_ERROR | RTIT_STATUS_STOPPED | \
	RTIT_STATUS_BYTECNT))

/*
 * List of MSRs that can be directly passed to the guest.
 * In addition to these x2apic and PT MSRs are handled specially.
 */
static u32 vmx_possible_passthrough_msrs[MAX_POSSIBLE_PASSTHROUGH_MSRS] = {
	MSR_IA32_SPEC_CTRL,
	MSR_IA32_PRED_CMD,
	MSR_IA32_FLUSH_CMD,
	MSR_IA32_TSC,
#ifdef CONFIG_X86_64
	MSR_FS_BASE,
	MSR_GS_BASE,
	MSR_KERNEL_GS_BASE,
	MSR_IA32_XFD,
	MSR_IA32_XFD_ERR,
#endif
	MSR_IA32_SYSENTER_CS,
	MSR_IA32_SYSENTER_ESP,
	MSR_IA32_SYSENTER_EIP,
	MSR_CORE_C1_RES,
	MSR_CORE_C3_RESIDENCY,
	MSR_CORE_C6_RESIDENCY,
	MSR_CORE_C7_RESIDENCY,
};

/*
 * These 2 parameters are used to config the controls for Pause-Loop Exiting:
 * ple_gap:    upper bound on the amount of time between two successive
 *             executions of PAUSE in a loop. Also indicate if ple enabled.
 *             According to test, this time is usually smaller than 128 cycles.
 * ple_window: upper bound on the amount of time a guest is allowed to execute
 *             in a PAUSE loop. Tests indicate that most spinlocks are held for
 *             less than 2^12 cycles
 * Time is measured based on a counter that runs at the same rate as the TSC,
 * refer SDM volume 3b section 21.6.13 & 22.1.3.
 */
static unsigned int ple_gap = KVM_DEFAULT_PLE_GAP;
module_param(ple_gap, uint, 0444);

static unsigned int ple_window = KVM_VMX_DEFAULT_PLE_WINDOW;
module_param(ple_window, uint, 0444);

/* Default doubles per-vcpu window every exit. */
static unsigned int ple_window_grow = KVM_DEFAULT_PLE_WINDOW_GROW;
module_param(ple_window_grow, uint, 0444);

/* Default resets per-vcpu window every exit to ple_window. */
static unsigned int ple_window_shrink = KVM_DEFAULT_PLE_WINDOW_SHRINK;
module_param(ple_window_shrink, uint, 0444);

/* Default is to compute the maximum so we can never overflow. */
static unsigned int ple_window_max        = KVM_VMX_DEFAULT_PLE_WINDOW_MAX;
module_param(ple_window_max, uint, 0444);

/* Default is SYSTEM mode, 1 for host-guest mode */
int __read_mostly pt_mode = PT_MODE_SYSTEM;
module_param(pt_mode, int, S_IRUGO);

static DEFINE_STATIC_KEY_FALSE(vmx_l1d_should_flush);
static DEFINE_STATIC_KEY_FALSE(vmx_l1d_flush_cond);
static DEFINE_MUTEX(vmx_l1d_flush_mutex);

/* Storage for pre module init parameter parsing */
static enum vmx_l1d_flush_state __read_mostly vmentry_l1d_flush_param = VMENTER_L1D_FLUSH_AUTO;

static const struct {
	const char *option;
	bool for_parse;
} vmentry_l1d_param[] = {
	[VMENTER_L1D_FLUSH_AUTO]	 = {"auto", true},
	[VMENTER_L1D_FLUSH_NEVER]	 = {"never", true},
	[VMENTER_L1D_FLUSH_COND]	 = {"cond", true},
	[VMENTER_L1D_FLUSH_ALWAYS]	 = {"always", true},
	[VMENTER_L1D_FLUSH_EPT_DISABLED] = {"EPT disabled", false},
	[VMENTER_L1D_FLUSH_NOT_REQUIRED] = {"not required", false},
};

#define L1D_CACHE_ORDER 4
static void *vmx_l1d_flush_pages;

static int vmx_setup_l1d_flush(enum vmx_l1d_flush_state l1tf)
{
	struct page *page;
	unsigned int i;

	if (!boot_cpu_has_bug(X86_BUG_L1TF)) {
		l1tf_vmx_mitigation = VMENTER_L1D_FLUSH_NOT_REQUIRED;
		return 0;
	}

	if (!enable_ept) {
		l1tf_vmx_mitigation = VMENTER_L1D_FLUSH_EPT_DISABLED;
		return 0;
	}

	if (host_arch_capabilities & ARCH_CAP_SKIP_VMENTRY_L1DFLUSH) {
		l1tf_vmx_mitigation = VMENTER_L1D_FLUSH_NOT_REQUIRED;
		return 0;
	}

	/* If set to auto use the default l1tf mitigation method */
	if (l1tf == VMENTER_L1D_FLUSH_AUTO) {
		switch (l1tf_mitigation) {
		case L1TF_MITIGATION_OFF:
			l1tf = VMENTER_L1D_FLUSH_NEVER;
			break;
		case L1TF_MITIGATION_FLUSH_NOWARN:
		case L1TF_MITIGATION_FLUSH:
		case L1TF_MITIGATION_FLUSH_NOSMT:
			l1tf = VMENTER_L1D_FLUSH_COND;
			break;
		case L1TF_MITIGATION_FULL:
		case L1TF_MITIGATION_FULL_FORCE:
			l1tf = VMENTER_L1D_FLUSH_ALWAYS;
			break;
		}
	} else if (l1tf_mitigation == L1TF_MITIGATION_FULL_FORCE) {
		l1tf = VMENTER_L1D_FLUSH_ALWAYS;
	}

	if (l1tf != VMENTER_L1D_FLUSH_NEVER && !vmx_l1d_flush_pages &&
	    !boot_cpu_has(X86_FEATURE_FLUSH_L1D)) {
		/*
		 * This allocation for vmx_l1d_flush_pages is not tied to a VM
		 * lifetime and so should not be charged to a memcg.
		 */
		page = alloc_pages(GFP_KERNEL, L1D_CACHE_ORDER);
		if (!page)
			return -ENOMEM;
		vmx_l1d_flush_pages = page_address(page);

		/*
		 * Initialize each page with a different pattern in
		 * order to protect against KSM in the nested
		 * virtualization case.
		 */
		for (i = 0; i < 1u << L1D_CACHE_ORDER; ++i) {
			memset(vmx_l1d_flush_pages + i * PAGE_SIZE, i + 1,
			       PAGE_SIZE);
		}
	}

	l1tf_vmx_mitigation = l1tf;

	if (l1tf != VMENTER_L1D_FLUSH_NEVER)
		static_branch_enable(&vmx_l1d_should_flush);
	else
		static_branch_disable(&vmx_l1d_should_flush);

	if (l1tf == VMENTER_L1D_FLUSH_COND)
		static_branch_enable(&vmx_l1d_flush_cond);
	else
		static_branch_disable(&vmx_l1d_flush_cond);
	return 0;
}

static int vmentry_l1d_flush_parse(const char *s)
{
	unsigned int i;

	if (s) {
		for (i = 0; i < ARRAY_SIZE(vmentry_l1d_param); i++) {
			if (vmentry_l1d_param[i].for_parse &&
			    sysfs_streq(s, vmentry_l1d_param[i].option))
				return i;
		}
	}
	return -EINVAL;
}

static int vmentry_l1d_flush_set(const char *s, const struct kernel_param *kp)
{
	int l1tf, ret;

	l1tf = vmentry_l1d_flush_parse(s);
	if (l1tf < 0)
		return l1tf;

	if (!boot_cpu_has(X86_BUG_L1TF))
		return 0;

	/*
	 * Has vmx_init() run already? If not then this is the pre init
	 * parameter parsing. In that case just store the value and let
	 * vmx_init() do the proper setup after enable_ept has been
	 * established.
	 */
	if (l1tf_vmx_mitigation == VMENTER_L1D_FLUSH_AUTO) {
		vmentry_l1d_flush_param = l1tf;
		return 0;
	}

	mutex_lock(&vmx_l1d_flush_mutex);
	ret = vmx_setup_l1d_flush(l1tf);
	mutex_unlock(&vmx_l1d_flush_mutex);
	return ret;
}

static int vmentry_l1d_flush_get(char *s, const struct kernel_param *kp)
{
	if (WARN_ON_ONCE(l1tf_vmx_mitigation >= ARRAY_SIZE(vmentry_l1d_param)))
		return sysfs_emit(s, "???\n");

	return sysfs_emit(s, "%s\n", vmentry_l1d_param[l1tf_vmx_mitigation].option);
}

static __always_inline void vmx_disable_fb_clear(struct vcpu_vmx *vmx)
{
	u64 msr;

	if (!vmx->disable_fb_clear)
		return;

	msr = __rdmsr(MSR_IA32_MCU_OPT_CTRL);
	msr |= FB_CLEAR_DIS;
	native_wrmsrl(MSR_IA32_MCU_OPT_CTRL, msr);
	/* Cache the MSR value to avoid reading it later */
	vmx->msr_ia32_mcu_opt_ctrl = msr;
}

static __always_inline void vmx_enable_fb_clear(struct vcpu_vmx *vmx)
{
	if (!vmx->disable_fb_clear)
		return;

	vmx->msr_ia32_mcu_opt_ctrl &= ~FB_CLEAR_DIS;
	native_wrmsrl(MSR_IA32_MCU_OPT_CTRL, vmx->msr_ia32_mcu_opt_ctrl);
}

static void vmx_update_fb_clear_dis(struct kvm_vcpu *vcpu, struct vcpu_vmx *vmx)
{
	vmx->disable_fb_clear = (host_arch_capabilities & ARCH_CAP_FB_CLEAR_CTRL) &&
				!boot_cpu_has_bug(X86_BUG_MDS) &&
				!boot_cpu_has_bug(X86_BUG_TAA);

	/*
	 * If guest will not execute VERW, there is no need to set FB_CLEAR_DIS
	 * at VMEntry. Skip the MSR read/write when a guest has no use case to
	 * execute VERW.
	 */
	if ((vcpu->arch.arch_capabilities & ARCH_CAP_FB_CLEAR) ||
	   ((vcpu->arch.arch_capabilities & ARCH_CAP_MDS_NO) &&
	    (vcpu->arch.arch_capabilities & ARCH_CAP_TAA_NO) &&
	    (vcpu->arch.arch_capabilities & ARCH_CAP_PSDP_NO) &&
	    (vcpu->arch.arch_capabilities & ARCH_CAP_FBSDP_NO) &&
	    (vcpu->arch.arch_capabilities & ARCH_CAP_SBDR_SSDP_NO)))
		vmx->disable_fb_clear = false;
}

static const struct kernel_param_ops vmentry_l1d_flush_ops = {
	.set = vmentry_l1d_flush_set,
	.get = vmentry_l1d_flush_get,
};
module_param_cb(vmentry_l1d_flush, &vmentry_l1d_flush_ops, NULL, 0644);

static u32 vmx_segment_access_rights(struct kvm_segment *var);

void vmx_vmexit(void);

#define vmx_insn_failed(fmt...)		\
do {					\
	WARN_ONCE(1, fmt);		\
	pr_warn_ratelimited(fmt);	\
} while (0)

noinline void vmread_error(unsigned long field)
{
	vmx_insn_failed("vmread failed: field=%lx\n", field);
}

#ifndef CONFIG_CC_HAS_ASM_GOTO_OUTPUT
noinstr void vmread_error_trampoline2(unsigned long field, bool fault)
{
	if (fault) {
		kvm_spurious_fault();
	} else {
		instrumentation_begin();
		vmread_error(field);
		instrumentation_end();
	}
}
#endif

noinline void vmwrite_error(unsigned long field, unsigned long value)
{
	vmx_insn_failed("vmwrite failed: field=%lx val=%lx err=%u\n",
			field, value, vmcs_read32(VM_INSTRUCTION_ERROR));
}

noinline void vmclear_error(struct vmcs *vmcs, u64 phys_addr)
{
	vmx_insn_failed("vmclear failed: %p/%llx err=%u\n",
			vmcs, phys_addr, vmcs_read32(VM_INSTRUCTION_ERROR));
}

noinline void vmptrld_error(struct vmcs *vmcs, u64 phys_addr)
{
	vmx_insn_failed("vmptrld failed: %p/%llx err=%u\n",
			vmcs, phys_addr, vmcs_read32(VM_INSTRUCTION_ERROR));
}

noinline void invvpid_error(unsigned long ext, u16 vpid, gva_t gva)
{
	vmx_insn_failed("invvpid failed: ext=0x%lx vpid=%u gva=0x%lx\n",
			ext, vpid, gva);
}

noinline void invept_error(unsigned long ext, u64 eptp, gpa_t gpa)
{
	vmx_insn_failed("invept failed: ext=0x%lx eptp=%llx gpa=0x%llx\n",
			ext, eptp, gpa);
}

static DEFINE_PER_CPU(struct vmcs *, vmxarea);
DEFINE_PER_CPU(struct vmcs *, current_vmcs);
/*
 * We maintain a per-CPU linked-list of VMCS loaded on that CPU. This is needed
 * when a CPU is brought down, and we need to VMCLEAR all VMCSs loaded on it.
 */
static DEFINE_PER_CPU(struct list_head, loaded_vmcss_on_cpu);

static DECLARE_BITMAP(vmx_vpid_bitmap, VMX_NR_VPIDS);
static DEFINE_SPINLOCK(vmx_vpid_lock);

struct vmcs_config vmcs_config __ro_after_init;
struct vmx_capability vmx_capability __ro_after_init;

#define VMX_SEGMENT_FIELD(seg)					\
	[VCPU_SREG_##seg] = {                                   \
		.selector = GUEST_##seg##_SELECTOR,		\
		.base = GUEST_##seg##_BASE,		   	\
		.limit = GUEST_##seg##_LIMIT,		   	\
		.ar_bytes = GUEST_##seg##_AR_BYTES,	   	\
	}

static const struct kvm_vmx_segment_field {
	unsigned selector;
	unsigned base;
	unsigned limit;
	unsigned ar_bytes;
} kvm_vmx_segment_fields[] = {
	VMX_SEGMENT_FIELD(CS),
	VMX_SEGMENT_FIELD(DS),
	VMX_SEGMENT_FIELD(ES),
	VMX_SEGMENT_FIELD(FS),
	VMX_SEGMENT_FIELD(GS),
	VMX_SEGMENT_FIELD(SS),
	VMX_SEGMENT_FIELD(TR),
	VMX_SEGMENT_FIELD(LDTR),
};

static inline void vmx_segment_cache_clear(struct vcpu_vmx *vmx)
{
	vmx->segment_cache.bitmask = 0;
}

static unsigned long host_idt_base;

#if IS_ENABLED(CONFIG_HYPERV)
static struct kvm_x86_ops vmx_x86_ops __initdata;

static bool __read_mostly enlightened_vmcs = true;
module_param(enlightened_vmcs, bool, 0444);

static int hv_enable_l2_tlb_flush(struct kvm_vcpu *vcpu)
{
	struct hv_enlightened_vmcs *evmcs;
	struct hv_partition_assist_pg **p_hv_pa_pg =
			&to_kvm_hv(vcpu->kvm)->hv_pa_pg;
	/*
	 * Synthetic VM-Exit is not enabled in current code and so All
	 * evmcs in singe VM shares same assist page.
	 */
	if (!*p_hv_pa_pg)
		*p_hv_pa_pg = kzalloc(PAGE_SIZE, GFP_KERNEL_ACCOUNT);

	if (!*p_hv_pa_pg)
		return -ENOMEM;

	evmcs = (struct hv_enlightened_vmcs *)to_vmx(vcpu)->loaded_vmcs->vmcs;

	evmcs->partition_assist_page =
		__pa(*p_hv_pa_pg);
	evmcs->hv_vm_id = (unsigned long)vcpu->kvm;
	evmcs->hv_enlightenments_control.nested_flush_hypercall = 1;

	return 0;
}

static __init void hv_init_evmcs(void)
{
	int cpu;

	if (!enlightened_vmcs)
		return;

	/*
	 * Enlightened VMCS usage should be recommended and the host needs
	 * to support eVMCS v1 or above.
	 */
	if (ms_hyperv.hints & HV_X64_ENLIGHTENED_VMCS_RECOMMENDED &&
	    (ms_hyperv.nested_features & HV_X64_ENLIGHTENED_VMCS_VERSION) >=
	     KVM_EVMCS_VERSION) {

		/* Check that we have assist pages on all online CPUs */
		for_each_online_cpu(cpu) {
			if (!hv_get_vp_assist_page(cpu)) {
				enlightened_vmcs = false;
				break;
			}
		}

		if (enlightened_vmcs) {
			pr_info("Using Hyper-V Enlightened VMCS\n");
			static_branch_enable(&__kvm_is_using_evmcs);
		}

		if (ms_hyperv.nested_features & HV_X64_NESTED_DIRECT_FLUSH)
			vmx_x86_ops.enable_l2_tlb_flush
				= hv_enable_l2_tlb_flush;

	} else {
		enlightened_vmcs = false;
	}
}

static void hv_reset_evmcs(void)
{
	struct hv_vp_assist_page *vp_ap;

	if (!kvm_is_using_evmcs())
		return;

	/*
	 * KVM should enable eVMCS if and only if all CPUs have a VP assist
	 * page, and should reject CPU onlining if eVMCS is enabled the CPU
	 * doesn't have a VP assist page allocated.
	 */
	vp_ap = hv_get_vp_assist_page(smp_processor_id());
	if (WARN_ON_ONCE(!vp_ap))
		return;

	/*
	 * Reset everything to support using non-enlightened VMCS access later
	 * (e.g. when we reload the module with enlightened_vmcs=0)
	 */
	vp_ap->nested_control.features.directhypercall = 0;
	vp_ap->current_nested_vmcs = 0;
	vp_ap->enlighten_vmentry = 0;
}

#else /* IS_ENABLED(CONFIG_HYPERV) */
static void hv_init_evmcs(void) {}
static void hv_reset_evmcs(void) {}
#endif /* IS_ENABLED(CONFIG_HYPERV) */

/*
 * Comment's format: document - errata name - stepping - processor name.
 * Refer from
 * https://www.virtualbox.org/svn/vbox/trunk/src/VBox/VMM/VMMR0/HMR0.cpp
 */
static u32 vmx_preemption_cpu_tfms[] = {
/* 323344.pdf - BA86   - D0 - Xeon 7500 Series */
0x000206E6,
/* 323056.pdf - AAX65  - C2 - Xeon L3406 */
/* 322814.pdf - AAT59  - C2 - i7-600, i5-500, i5-400 and i3-300 Mobile */
/* 322911.pdf - AAU65  - C2 - i5-600, i3-500 Desktop and Pentium G6950 */
0x00020652,
/* 322911.pdf - AAU65  - K0 - i5-600, i3-500 Desktop and Pentium G6950 */
0x00020655,
/* 322373.pdf - AAO95  - B1 - Xeon 3400 Series */
/* 322166.pdf - AAN92  - B1 - i7-800 and i5-700 Desktop */
/*
 * 320767.pdf - AAP86  - B1 -
 * i7-900 Mobile Extreme, i7-800 and i7-700 Mobile
 */
0x000106E5,
/* 321333.pdf - AAM126 - C0 - Xeon 3500 */
0x000106A0,
/* 321333.pdf - AAM126 - C1 - Xeon 3500 */
0x000106A1,
/* 320836.pdf - AAJ124 - C0 - i7-900 Desktop Extreme and i7-900 Desktop */
0x000106A4,
 /* 321333.pdf - AAM126 - D0 - Xeon 3500 */
 /* 321324.pdf - AAK139 - D0 - Xeon 5500 */
 /* 320836.pdf - AAJ124 - D0 - i7-900 Extreme and i7-900 Desktop */
0x000106A5,
 /* Xeon E3-1220 V2 */
0x000306A8,
};

static inline bool cpu_has_broken_vmx_preemption_timer(void)
{
	u32 eax = cpuid_eax(0x00000001), i;

	/* Clear the reserved bits */
	eax &= ~(0x3U << 14 | 0xfU << 28);
	for (i = 0; i < ARRAY_SIZE(vmx_preemption_cpu_tfms); i++)
		if (eax == vmx_preemption_cpu_tfms[i])
			return true;

	return false;
}

static inline bool cpu_need_virtualize_apic_accesses(struct kvm_vcpu *vcpu)
{
	return flexpriority_enabled && lapic_in_kernel(vcpu);
}

static int possible_passthrough_msr_slot(u32 msr)
{
	u32 i;

	for (i = 0; i < ARRAY_SIZE(vmx_possible_passthrough_msrs); i++)
		if (vmx_possible_passthrough_msrs[i] == msr)
			return i;

	return -ENOENT;
}

static bool is_valid_passthrough_msr(u32 msr)
{
	bool r;

	switch (msr) {
	case 0x800 ... 0x8ff:
		/* x2APIC MSRs. These are handled in vmx_update_msr_bitmap_x2apic() */
		return true;
	case MSR_IA32_RTIT_STATUS:
	case MSR_IA32_RTIT_OUTPUT_BASE:
	case MSR_IA32_RTIT_OUTPUT_MASK:
	case MSR_IA32_RTIT_CR3_MATCH:
	case MSR_IA32_RTIT_ADDR0_A ... MSR_IA32_RTIT_ADDR3_B:
		/* PT MSRs. These are handled in pt_update_intercept_for_msr() */
	case MSR_LBR_SELECT:
	case MSR_LBR_TOS:
	case MSR_LBR_INFO_0 ... MSR_LBR_INFO_0 + 31:
	case MSR_LBR_NHM_FROM ... MSR_LBR_NHM_FROM + 31:
	case MSR_LBR_NHM_TO ... MSR_LBR_NHM_TO + 31:
	case MSR_LBR_CORE_FROM ... MSR_LBR_CORE_FROM + 8:
	case MSR_LBR_CORE_TO ... MSR_LBR_CORE_TO + 8:
		/* LBR MSRs. These are handled in vmx_update_intercept_for_lbr_msrs() */
		return true;
	}

	r = possible_passthrough_msr_slot(msr) != -ENOENT;

	WARN(!r, "Invalid MSR %x, please adapt vmx_possible_passthrough_msrs[]", msr);

	return r;
}

struct vmx_uret_msr *vmx_find_uret_msr(struct vcpu_vmx *vmx, u32 msr)
{
	int i;

	i = kvm_find_user_return_msr(msr);
	if (i >= 0)
		return &vmx->guest_uret_msrs[i];
	return NULL;
}

static int vmx_set_guest_uret_msr(struct vcpu_vmx *vmx,
				  struct vmx_uret_msr *msr, u64 data)
{
	unsigned int slot = msr - vmx->guest_uret_msrs;
	int ret = 0;

	if (msr->load_into_hardware) {
		preempt_disable();
		ret = kvm_set_user_return_msr(slot, data, msr->mask);
		preempt_enable();
	}
	if (!ret)
		msr->data = data;
	return ret;
}

/*
 * Disable VMX and clear CR4.VMXE (even if VMXOFF faults)
 *
 * Note, VMXOFF causes a #UD if the CPU is !post-VMXON, but it's impossible to
 * atomically track post-VMXON state, e.g. this may be called in NMI context.
 * Eat all faults as all other faults on VMXOFF faults are mode related, i.e.
 * faults are guaranteed to be due to the !post-VMXON check unless the CPU is
 * magically in RM, VM86, compat mode, or at CPL>0.
 */
static int kvm_cpu_vmxoff(void)
{
	asm_volatile_goto("1: vmxoff\n\t"
			  _ASM_EXTABLE(1b, %l[fault])
			  ::: "cc", "memory" : fault);

	cr4_clear_bits(X86_CR4_VMXE);
	return 0;

fault:
	cr4_clear_bits(X86_CR4_VMXE);
	return -EIO;
}

static void vmx_emergency_disable(void)
{
	int cpu = raw_smp_processor_id();
	struct loaded_vmcs *v;

	kvm_rebooting = true;

	/*
	 * Note, CR4.VMXE can be _cleared_ in NMI context, but it can only be
	 * set in task context.  If this races with VMX is disabled by an NMI,
	 * VMCLEAR and VMXOFF may #UD, but KVM will eat those faults due to
	 * kvm_rebooting set.
	 */
	if (!(__read_cr4() & X86_CR4_VMXE))
		return;

	list_for_each_entry(v, &per_cpu(loaded_vmcss_on_cpu, cpu),
			    loaded_vmcss_on_cpu_link)
		vmcs_clear(v->vmcs);

	kvm_cpu_vmxoff();
}

static void __loaded_vmcs_clear(void *arg)
{
	struct loaded_vmcs *loaded_vmcs = arg;
	int cpu = raw_smp_processor_id();

	if (loaded_vmcs->cpu != cpu)
		return; /* vcpu migration can race with cpu offline */
	if (per_cpu(current_vmcs, cpu) == loaded_vmcs->vmcs)
		per_cpu(current_vmcs, cpu) = NULL;

	vmcs_clear(loaded_vmcs->vmcs);
	if (loaded_vmcs->shadow_vmcs && loaded_vmcs->launched)
		vmcs_clear(loaded_vmcs->shadow_vmcs);

	list_del(&loaded_vmcs->loaded_vmcss_on_cpu_link);

	/*
	 * Ensure all writes to loaded_vmcs, including deleting it from its
	 * current percpu list, complete before setting loaded_vmcs->cpu to
	 * -1, otherwise a different cpu can see loaded_vmcs->cpu == -1 first
	 * and add loaded_vmcs to its percpu list before it's deleted from this
	 * cpu's list. Pairs with the smp_rmb() in vmx_vcpu_load_vmcs().
	 */
	smp_wmb();

	loaded_vmcs->cpu = -1;
	loaded_vmcs->launched = 0;
}

void loaded_vmcs_clear(struct loaded_vmcs *loaded_vmcs)
{
	int cpu = loaded_vmcs->cpu;

	if (cpu != -1)
		smp_call_function_single(cpu,
			 __loaded_vmcs_clear, loaded_vmcs, 1);
}

static bool vmx_segment_cache_test_set(struct vcpu_vmx *vmx, unsigned seg,
				       unsigned field)
{
	bool ret;
	u32 mask = 1 << (seg * SEG_FIELD_NR + field);

	if (!kvm_register_is_available(&vmx->vcpu, VCPU_EXREG_SEGMENTS)) {
		kvm_register_mark_available(&vmx->vcpu, VCPU_EXREG_SEGMENTS);
		vmx->segment_cache.bitmask = 0;
	}
	ret = vmx->segment_cache.bitmask & mask;
	vmx->segment_cache.bitmask |= mask;
	return ret;
}

static u16 vmx_read_guest_seg_selector(struct vcpu_vmx *vmx, unsigned seg)
{
	u16 *p = &vmx->segment_cache.seg[seg].selector;

	if (!vmx_segment_cache_test_set(vmx, seg, SEG_FIELD_SEL))
		*p = vmcs_read16(kvm_vmx_segment_fields[seg].selector);
	return *p;
}

static ulong vmx_read_guest_seg_base(struct vcpu_vmx *vmx, unsigned seg)
{
	ulong *p = &vmx->segment_cache.seg[seg].base;

	if (!vmx_segment_cache_test_set(vmx, seg, SEG_FIELD_BASE))
		*p = vmcs_readl(kvm_vmx_segment_fields[seg].base);
	return *p;
}

static u32 vmx_read_guest_seg_limit(struct vcpu_vmx *vmx, unsigned seg)
{
	u32 *p = &vmx->segment_cache.seg[seg].limit;

	if (!vmx_segment_cache_test_set(vmx, seg, SEG_FIELD_LIMIT))
		*p = vmcs_read32(kvm_vmx_segment_fields[seg].limit);
	return *p;
}

static u32 vmx_read_guest_seg_ar(struct vcpu_vmx *vmx, unsigned seg)
{
	u32 *p = &vmx->segment_cache.seg[seg].ar;

	if (!vmx_segment_cache_test_set(vmx, seg, SEG_FIELD_AR))
		*p = vmcs_read32(kvm_vmx_segment_fields[seg].ar_bytes);
	return *p;
}

void vmx_update_exception_bitmap(struct kvm_vcpu *vcpu)
{
	u32 eb;

	eb = (1u << PF_VECTOR) | (1u << UD_VECTOR) | (1u << MC_VECTOR) |
	     (1u << DB_VECTOR) | (1u << AC_VECTOR);
	/*
	 * Guest access to VMware backdoor ports could legitimately
	 * trigger #GP because of TSS I/O permission bitmap.
	 * We intercept those #GP and allow access to them anyway
	 * as VMware does.
	 */
	if (enable_vmware_backdoor)
		eb |= (1u << GP_VECTOR);
	if ((vcpu->guest_debug &
	     (KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_SW_BP)) ==
	    (KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_SW_BP))
		eb |= 1u << BP_VECTOR;
	if (to_vmx(vcpu)->rmode.vm86_active)
		eb = ~0;
	if (!vmx_need_pf_intercept(vcpu))
		eb &= ~(1u << PF_VECTOR);

	/* When we are running a nested L2 guest and L1 specified for it a
	 * certain exception bitmap, we must trap the same exceptions and pass
	 * them to L1. When running L2, we will only handle the exceptions
	 * specified above if L1 did not want them.
	 */
	if (is_guest_mode(vcpu))
		eb |= get_vmcs12(vcpu)->exception_bitmap;
	else {
		int mask = 0, match = 0;

		if (enable_ept && (eb & (1u << PF_VECTOR))) {
			/*
			 * If EPT is enabled, #PF is currently only intercepted
			 * if MAXPHYADDR is smaller on the guest than on the
			 * host.  In that case we only care about present,
			 * non-reserved faults.  For vmcs02, however, PFEC_MASK
			 * and PFEC_MATCH are set in prepare_vmcs02_rare.
			 */
			mask = PFERR_PRESENT_MASK | PFERR_RSVD_MASK;
			match = PFERR_PRESENT_MASK;
		}
		vmcs_write32(PAGE_FAULT_ERROR_CODE_MASK, mask);
		vmcs_write32(PAGE_FAULT_ERROR_CODE_MATCH, match);
	}

	/*
	 * Disabling xfd interception indicates that dynamic xfeatures
	 * might be used in the guest. Always trap #NM in this case
	 * to save guest xfd_err timely.
	 */
	if (vcpu->arch.xfd_no_write_intercept)
		eb |= (1u << NM_VECTOR);

	vmcs_write32(EXCEPTION_BITMAP, eb);
}

/*
 * Check if MSR is intercepted for currently loaded MSR bitmap.
 */
static bool msr_write_intercepted(struct vcpu_vmx *vmx, u32 msr)
{
	if (!(exec_controls_get(vmx) & CPU_BASED_USE_MSR_BITMAPS))
		return true;

	return vmx_test_msr_bitmap_write(vmx->loaded_vmcs->msr_bitmap, msr);
}

unsigned int __vmx_vcpu_run_flags(struct vcpu_vmx *vmx)
{
	unsigned int flags = 0;

	if (vmx->loaded_vmcs->launched)
		flags |= VMX_RUN_VMRESUME;

	/*
	 * If writes to the SPEC_CTRL MSR aren't intercepted, the guest is free
	 * to change it directly without causing a vmexit.  In that case read
	 * it after vmexit and store it in vmx->spec_ctrl.
	 */
	if (!msr_write_intercepted(vmx, MSR_IA32_SPEC_CTRL))
		flags |= VMX_RUN_SAVE_SPEC_CTRL;

	return flags;
}

static __always_inline void clear_atomic_switch_msr_special(struct vcpu_vmx *vmx,
		unsigned long entry, unsigned long exit)
{
	vm_entry_controls_clearbit(vmx, entry);
	vm_exit_controls_clearbit(vmx, exit);
}

int vmx_find_loadstore_msr_slot(struct vmx_msrs *m, u32 msr)
{
	unsigned int i;

	for (i = 0; i < m->nr; ++i) {
		if (m->val[i].index == msr)
			return i;
	}
	return -ENOENT;
}

static void clear_atomic_switch_msr(struct vcpu_vmx *vmx, unsigned msr)
{
	int i;
	struct msr_autoload *m = &vmx->msr_autoload;

	switch (msr) {
	case MSR_EFER:
		if (cpu_has_load_ia32_efer()) {
			clear_atomic_switch_msr_special(vmx,
					VM_ENTRY_LOAD_IA32_EFER,
					VM_EXIT_LOAD_IA32_EFER);
			return;
		}
		break;
	case MSR_CORE_PERF_GLOBAL_CTRL:
		if (cpu_has_load_perf_global_ctrl()) {
			clear_atomic_switch_msr_special(vmx,
					VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL,
					VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL);
			return;
		}
		break;
	}
	i = vmx_find_loadstore_msr_slot(&m->guest, msr);
	if (i < 0)
		goto skip_guest;
	--m->guest.nr;
	m->guest.val[i] = m->guest.val[m->guest.nr];
	vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, m->guest.nr);

skip_guest:
	i = vmx_find_loadstore_msr_slot(&m->host, msr);
	if (i < 0)
		return;

	--m->host.nr;
	m->host.val[i] = m->host.val[m->host.nr];
	vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, m->host.nr);
}

static __always_inline void add_atomic_switch_msr_special(struct vcpu_vmx *vmx,
		unsigned long entry, unsigned long exit,
		unsigned long guest_val_vmcs, unsigned long host_val_vmcs,
		u64 guest_val, u64 host_val)
{
	vmcs_write64(guest_val_vmcs, guest_val);
	if (host_val_vmcs != HOST_IA32_EFER)
		vmcs_write64(host_val_vmcs, host_val);
	vm_entry_controls_setbit(vmx, entry);
	vm_exit_controls_setbit(vmx, exit);
}

static void add_atomic_switch_msr(struct vcpu_vmx *vmx, unsigned msr,
				  u64 guest_val, u64 host_val, bool entry_only)
{
	int i, j = 0;
	struct msr_autoload *m = &vmx->msr_autoload;

	switch (msr) {
	case MSR_EFER:
		if (cpu_has_load_ia32_efer()) {
			add_atomic_switch_msr_special(vmx,
					VM_ENTRY_LOAD_IA32_EFER,
					VM_EXIT_LOAD_IA32_EFER,
					GUEST_IA32_EFER,
					HOST_IA32_EFER,
					guest_val, host_val);
			return;
		}
		break;
	case MSR_CORE_PERF_GLOBAL_CTRL:
		if (cpu_has_load_perf_global_ctrl()) {
			add_atomic_switch_msr_special(vmx,
					VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL,
					VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL,
					GUEST_IA32_PERF_GLOBAL_CTRL,
					HOST_IA32_PERF_GLOBAL_CTRL,
					guest_val, host_val);
			return;
		}
		break;
	case MSR_IA32_PEBS_ENABLE:
		/* PEBS needs a quiescent period after being disabled (to write
		 * a record).  Disabling PEBS through VMX MSR swapping doesn't
		 * provide that period, so a CPU could write host's record into
		 * guest's memory.
		 */
		wrmsrl(MSR_IA32_PEBS_ENABLE, 0);
	}

	i = vmx_find_loadstore_msr_slot(&m->guest, msr);
	if (!entry_only)
		j = vmx_find_loadstore_msr_slot(&m->host, msr);

	if ((i < 0 && m->guest.nr == MAX_NR_LOADSTORE_MSRS) ||
	    (j < 0 &&  m->host.nr == MAX_NR_LOADSTORE_MSRS)) {
		printk_once(KERN_WARNING "Not enough msr switch entries. "
				"Can't add msr %x\n", msr);
		return;
	}
	if (i < 0) {
		i = m->guest.nr++;
		vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, m->guest.nr);
	}
	m->guest.val[i].index = msr;
	m->guest.val[i].value = guest_val;

	if (entry_only)
		return;

	if (j < 0) {
		j = m->host.nr++;
		vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, m->host.nr);
	}
	m->host.val[j].index = msr;
	m->host.val[j].value = host_val;
}

static bool update_transition_efer(struct vcpu_vmx *vmx)
{
	u64 guest_efer = vmx->vcpu.arch.efer;
	u64 ignore_bits = 0;
	int i;

	/* Shadow paging assumes NX to be available.  */
	if (!enable_ept)
		guest_efer |= EFER_NX;

	/*
	 * LMA and LME handled by hardware; SCE meaningless outside long mode.
	 */
	ignore_bits |= EFER_SCE;
#ifdef CONFIG_X86_64
	ignore_bits |= EFER_LMA | EFER_LME;
	/* SCE is meaningful only in long mode on Intel */
	if (guest_efer & EFER_LMA)
		ignore_bits &= ~(u64)EFER_SCE;
#endif

	/*
	 * On EPT, we can't emulate NX, so we must switch EFER atomically.
	 * On CPUs that support "load IA32_EFER", always switch EFER
	 * atomically, since it's faster than switching it manually.
	 */
	if (cpu_has_load_ia32_efer() ||
	    (enable_ept && ((vmx->vcpu.arch.efer ^ host_efer) & EFER_NX))) {
		if (!(guest_efer & EFER_LMA))
			guest_efer &= ~EFER_LME;
		if (guest_efer != host_efer)
			add_atomic_switch_msr(vmx, MSR_EFER,
					      guest_efer, host_efer, false);
		else
			clear_atomic_switch_msr(vmx, MSR_EFER);
		return false;
	}

	i = kvm_find_user_return_msr(MSR_EFER);
	if (i < 0)
		return false;

	clear_atomic_switch_msr(vmx, MSR_EFER);

	guest_efer &= ~ignore_bits;
	guest_efer |= host_efer & ignore_bits;

	vmx->guest_uret_msrs[i].data = guest_efer;
	vmx->guest_uret_msrs[i].mask = ~ignore_bits;

	return true;
}

#ifdef CONFIG_X86_32
/*
 * On 32-bit kernels, VM exits still load the FS and GS bases from the
 * VMCS rather than the segment table.  KVM uses this helper to figure
 * out the current bases to poke them into the VMCS before entry.
 */
static unsigned long segment_base(u16 selector)
{
	struct desc_struct *table;
	unsigned long v;

	if (!(selector & ~SEGMENT_RPL_MASK))
		return 0;

	table = get_current_gdt_ro();

	if ((selector & SEGMENT_TI_MASK) == SEGMENT_LDT) {
		u16 ldt_selector = kvm_read_ldt();

		if (!(ldt_selector & ~SEGMENT_RPL_MASK))
			return 0;

		table = (struct desc_struct *)segment_base(ldt_selector);
	}
	v = get_desc_base(&table[selector >> 3]);
	return v;
}
#endif

static inline bool pt_can_write_msr(struct vcpu_vmx *vmx)
{
	return vmx_pt_mode_is_host_guest() &&
	       !(vmx->pt_desc.guest.ctl & RTIT_CTL_TRACEEN);
}

static inline bool pt_output_base_valid(struct kvm_vcpu *vcpu, u64 base)
{
	/* The base must be 128-byte aligned and a legal physical address. */
	return kvm_vcpu_is_legal_aligned_gpa(vcpu, base, 128);
}

static inline void pt_load_msr(struct pt_ctx *ctx, u32 addr_range)
{
	u32 i;

	wrmsrl(MSR_IA32_RTIT_STATUS, ctx->status);
	wrmsrl(MSR_IA32_RTIT_OUTPUT_BASE, ctx->output_base);
	wrmsrl(MSR_IA32_RTIT_OUTPUT_MASK, ctx->output_mask);
	wrmsrl(MSR_IA32_RTIT_CR3_MATCH, ctx->cr3_match);
	for (i = 0; i < addr_range; i++) {
		wrmsrl(MSR_IA32_RTIT_ADDR0_A + i * 2, ctx->addr_a[i]);
		wrmsrl(MSR_IA32_RTIT_ADDR0_B + i * 2, ctx->addr_b[i]);
	}
}

static inline void pt_save_msr(struct pt_ctx *ctx, u32 addr_range)
{
	u32 i;

	rdmsrl(MSR_IA32_RTIT_STATUS, ctx->status);
	rdmsrl(MSR_IA32_RTIT_OUTPUT_BASE, ctx->output_base);
	rdmsrl(MSR_IA32_RTIT_OUTPUT_MASK, ctx->output_mask);
	rdmsrl(MSR_IA32_RTIT_CR3_MATCH, ctx->cr3_match);
	for (i = 0; i < addr_range; i++) {
		rdmsrl(MSR_IA32_RTIT_ADDR0_A + i * 2, ctx->addr_a[i]);
		rdmsrl(MSR_IA32_RTIT_ADDR0_B + i * 2, ctx->addr_b[i]);
	}
}

static void pt_guest_enter(struct vcpu_vmx *vmx)
{
	if (vmx_pt_mode_is_system())
		return;

	/*
	 * GUEST_IA32_RTIT_CTL is already set in the VMCS.
	 * Save host state before VM entry.
	 */
	rdmsrl(MSR_IA32_RTIT_CTL, vmx->pt_desc.host.ctl);
	if (vmx->pt_desc.guest.ctl & RTIT_CTL_TRACEEN) {
		wrmsrl(MSR_IA32_RTIT_CTL, 0);
		pt_save_msr(&vmx->pt_desc.host, vmx->pt_desc.num_address_ranges);
		pt_load_msr(&vmx->pt_desc.guest, vmx->pt_desc.num_address_ranges);
	}
}

static void pt_guest_exit(struct vcpu_vmx *vmx)
{
	if (vmx_pt_mode_is_system())
		return;

	if (vmx->pt_desc.guest.ctl & RTIT_CTL_TRACEEN) {
		pt_save_msr(&vmx->pt_desc.guest, vmx->pt_desc.num_address_ranges);
		pt_load_msr(&vmx->pt_desc.host, vmx->pt_desc.num_address_ranges);
	}

	/*
	 * KVM requires VM_EXIT_CLEAR_IA32_RTIT_CTL to expose PT to the guest,
	 * i.e. RTIT_CTL is always cleared on VM-Exit.  Restore it if necessary.
	 */
	if (vmx->pt_desc.host.ctl)
		wrmsrl(MSR_IA32_RTIT_CTL, vmx->pt_desc.host.ctl);
}

void vmx_set_host_fs_gs(struct vmcs_host_state *host, u16 fs_sel, u16 gs_sel,
			unsigned long fs_base, unsigned long gs_base)
{
	if (unlikely(fs_sel != host->fs_sel)) {
		if (!(fs_sel & 7))
			vmcs_write16(HOST_FS_SELECTOR, fs_sel);
		else
			vmcs_write16(HOST_FS_SELECTOR, 0);
		host->fs_sel = fs_sel;
	}
	if (unlikely(gs_sel != host->gs_sel)) {
		if (!(gs_sel & 7))
			vmcs_write16(HOST_GS_SELECTOR, gs_sel);
		else
			vmcs_write16(HOST_GS_SELECTOR, 0);
		host->gs_sel = gs_sel;
	}
	if (unlikely(fs_base != host->fs_base)) {
		vmcs_writel(HOST_FS_BASE, fs_base);
		host->fs_base = fs_base;
	}
	if (unlikely(gs_base != host->gs_base)) {
		vmcs_writel(HOST_GS_BASE, gs_base);
		host->gs_base = gs_base;
	}
}

void vmx_prepare_switch_to_guest(struct kvm_vcpu *vcpu)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	struct vmcs_host_state *host_state;
#ifdef CONFIG_X86_64
	int cpu = raw_smp_processor_id();
#endif
	unsigned long fs_base, gs_base;
	u16 fs_sel, gs_sel;
	int i;

	vmx->req_immediate_exit = false;

	/*
	 * Note that guest MSRs to be saved/restored can also be changed
	 * when guest state is loaded. This happens when guest transitions
	 * to/from long-mode by setting MSR_EFER.LMA.
	 */
	if (!vmx->guest_uret_msrs_loaded) {
		vmx->guest_uret_msrs_loaded = true;
		for (i = 0; i < kvm_nr_uret_msrs; ++i) {
			if (!vmx->guest_uret_msrs[i].load_into_hardware)
				continue;

			kvm_set_user_return_msr(i,
						vmx->guest_uret_msrs[i].data,
						vmx->guest_uret_msrs[i].mask);
		}
	}

	if (vmx->nested.need_vmcs12_to_shadow_sync)
		nested_sync_vmcs12_to_shadow(vcpu);

	if (vmx->guest_state_loaded)
		return;

	host_state = &vmx->loaded_vmcs->host_state;

	/*
	 * Set host fs and gs selectors.  Unfortunately, 22.2.3 does not
	 * allow segment selectors with cpl > 0 or ti == 1.
	 */
	host_state->ldt_sel = kvm_read_ldt();

#ifdef CONFIG_X86_64
	savesegment(ds, host_state->ds_sel);
	savesegment(es, host_state->es_sel);

	gs_base = cpu_kernelmode_gs_base(cpu);
	if (likely(is_64bit_mm(current->mm))) {
		current_save_fsgs();
		fs_sel = current->thread.fsindex;
		gs_sel = current->thread.gsindex;
		fs_base = current->thread.fsbase;
		vmx->msr_host_kernel_gs_base = current->thread.gsbase;
	} else {
		savesegment(fs, fs_sel);
		savesegment(gs, gs_sel);
		fs_base = read_msr(MSR_FS_BASE);
		vmx->msr_host_kernel_gs_base = read_msr(MSR_KERNEL_GS_BASE);
	}

	wrmsrl(MSR_KERNEL_GS_BASE, vmx->msr_guest_kernel_gs_base);
#else
	savesegment(fs, fs_sel);
	savesegment(gs, gs_sel);
	fs_base = segment_base(fs_sel);
	gs_base = segment_base(gs_sel);
#endif

	vmx_set_host_fs_gs(host_state, fs_sel, gs_sel, fs_base, gs_base);
	vmx->guest_state_loaded = true;
}

static void vmx_prepare_switch_to_host(struct vcpu_vmx *vmx)
{
	struct vmcs_host_state *host_state;

	if (!vmx->guest_state_loaded)
		return;

	host_state = &vmx->loaded_vmcs->host_state;

	++vmx->vcpu.stat.host_state_reload;

#ifdef CONFIG_X86_64
	rdmsrl(MSR_KERNEL_GS_BASE, vmx->msr_guest_kernel_gs_base);
#endif
	if (host_state->ldt_sel || (host_state->gs_sel & 7)) {
		kvm_load_ldt(host_state->ldt_sel);
#ifdef CONFIG_X86_64
		load_gs_index(host_state->gs_sel);
#else
		loadsegment(gs, host_state->gs_sel);
#endif
	}
	if (host_state->fs_sel & 7)
		loadsegment(fs, host_state->fs_sel);
#ifdef CONFIG_X86_64
	if (unlikely(host_state->ds_sel | host_state->es_sel)) {
		loadsegment(ds, host_state->ds_sel);
		loadsegment(es, host_state->es_sel);
	}
#endif
	invalidate_tss_limit();
#ifdef CONFIG_X86_64
	wrmsrl(MSR_KERNEL_GS_BASE, vmx->msr_host_kernel_gs_base);
#endif
	load_fixmap_gdt(raw_smp_processor_id());
	vmx->guest_state_loaded = false;
	vmx->guest_uret_msrs_loaded = false;
}

#ifdef CONFIG_X86_64
static u64 vmx_read_guest_kernel_gs_base(struct vcpu_vmx *vmx)
{
	preempt_disable();
	if (vmx->guest_state_loaded)
		rdmsrl(MSR_KERNEL_GS_BASE, vmx->msr_guest_kernel_gs_base);
	preempt_enable();
	return vmx->msr_guest_kernel_gs_base;
}

static void vmx_write_guest_kernel_gs_base(struct vcpu_vmx *vmx, u64 data)
{
	preempt_disable();
	if (vmx->guest_state_loaded)
		wrmsrl(MSR_KERNEL_GS_BASE, data);
	preempt_enable();
	vmx->msr_guest_kernel_gs_base = data;
}
#endif

void vmx_vcpu_load_vmcs(struct kvm_vcpu *vcpu, int cpu,
			struct loaded_vmcs *buddy)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	bool already_loaded = vmx->loaded_vmcs->cpu == cpu;
	struct vmcs *prev;

	if (!already_loaded) {
		loaded_vmcs_clear(vmx->loaded_vmcs);
		local_irq_disable();

		/*
		 * Ensure loaded_vmcs->cpu is read before adding loaded_vmcs to
		 * this cpu's percpu list, otherwise it may not yet be deleted
		 * from its previous cpu's percpu list.  Pairs with the
		 * smb_wmb() in __loaded_vmcs_clear().
		 */
		smp_rmb();

		list_add(&vmx->loaded_vmcs->loaded_vmcss_on_cpu_link,
			 &per_cpu(loaded_vmcss_on_cpu, cpu));
		local_irq_enable();
	}

	prev = per_cpu(current_vmcs, cpu);
	if (prev != vmx->loaded_vmcs->vmcs) {
		per_cpu(current_vmcs, cpu) = vmx->loaded_vmcs->vmcs;
		vmcs_load(vmx->loaded_vmcs->vmcs);

		/*
		 * No indirect branch prediction barrier needed when switching
		 * the active VMCS within a vCPU, unless IBRS is advertised to
		 * the vCPU.  To minimize the number of IBPBs executed, KVM
		 * performs IBPB on nested VM-Exit (a single nested transition
		 * may switch the active VMCS multiple times).
		 */
		if (!buddy || WARN_ON_ONCE(buddy->vmcs != prev))
			indirect_branch_prediction_barrier();
	}

	if (!already_loaded) {
		void *gdt = get_current_gdt_ro();

		/*
		 * Flush all EPTP/VPID contexts, the new pCPU may have stale
		 * TLB entries from its previous association with the vCPU.
		 */
		kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu);

		/*
		 * Linux uses per-cpu TSS and GDT, so set these when switching
		 * processors.  See 22.2.4.
		 */
		vmcs_writel(HOST_TR_BASE,
			    (unsigned long)&get_cpu_entry_area(cpu)->tss.x86_tss);
		vmcs_writel(HOST_GDTR_BASE, (unsigned long)gdt);   /* 22.2.4 */

		if (IS_ENABLED(CONFIG_IA32_EMULATION) || IS_ENABLED(CONFIG_X86_32)) {
			/* 22.2.3 */
			vmcs_writel(HOST_IA32_SYSENTER_ESP,
				    (unsigned long)(cpu_entry_stack(cpu) + 1));
		}

		vmx->loaded_vmcs->cpu = cpu;
	}
}

/*
 * Switches to specified vcpu, until a matching vcpu_put(), but assumes
 * vcpu mutex is already taken.
 */
static void vmx_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);

	vmx_vcpu_load_vmcs(vcpu, cpu, NULL);

	vmx_vcpu_pi_load(vcpu, cpu);

	vmx->host_debugctlmsr = get_debugctlmsr();
}

static void vmx_vcpu_put(struct kvm_vcpu *vcpu)
{
	vmx_vcpu_pi_put(vcpu);

	vmx_prepare_switch_to_host(to_vmx(vcpu));
}

bool vmx_emulation_required(struct kvm_vcpu *vcpu)
{
	return emulate_invalid_guest_state && !vmx_guest_state_valid(vcpu);
}

unsigned long vmx_get_rflags(struct kvm_vcpu *vcpu)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	unsigned long rflags, save_rflags;

	if (!kvm_register_is_available(vcpu, VCPU_EXREG_RFLAGS)) {
		kvm_register_mark_available(vcpu, VCPU_EXREG_RFLAGS);
		rflags = vmcs_readl(GUEST_RFLAGS);
		if (vmx->rmode.vm86_active) {
			rflags &= RMODE_GUEST_OWNED_EFLAGS_BITS;
			save_rflags = vmx->rmode.save_rflags;
			rflags |= save_rflags & ~RMODE_GUEST_OWNED_EFLAGS_BITS;
		}
		vmx->rflags = rflags;
	}
	return vmx->rflags;
}

void vmx_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	unsigned long old_rflags;

	/*
	 * Unlike CR0 and CR4, RFLAGS handling requires checking if the vCPU
	 * is an unrestricted guest in order to mark L2 as needing emulation
	 * if L1 runs L2 as a restricted guest.
	 */
	if (is_unrestricted_guest(vcpu)) {
		kvm_register_mark_available(vcpu, VCPU_EXREG_RFLAGS);
		vmx->rflags = rflags;
		vmcs_writel(GUEST_RFLAGS, rflags);
		return;
	}

	old_rflags = vmx_get_rflags(vcpu);
	vmx->rflags = rflags;
	if (vmx->rmode.vm86_active) {
		vmx->rmode.save_rflags = rflags;
		rflags |= X86_EFLAGS_IOPL | X86_EFLAGS_VM;
	}
	vmcs_writel(GUEST_RFLAGS, rflags);

	if ((old_rflags ^ vmx->rflags) & X86_EFLAGS_VM)
		vmx->emulation_required = vmx_emulation_required(vcpu);
}

static bool vmx_get_if_flag(struct kvm_vcpu *vcpu)
{
	return vmx_get_rflags(vcpu) & X86_EFLAGS_IF;
}

u32 vmx_get_interrupt_shadow(struct kvm_vcpu *vcpu)
{
	u32 interruptibility = vmcs_read32(GUEST_INTERRUPTIBILITY_INFO);
	int ret = 0;

	if (interruptibility & GUEST_INTR_STATE_STI)
		ret |= KVM_X86_SHADOW_INT_STI;
	if (interruptibility & GUEST_INTR_STATE_MOV_SS)
		ret |= KVM_X86_SHADOW_INT_MOV_SS;

	return ret;
}

void vmx_set_interrupt_shadow(struct kvm_vcpu *vcpu, int mask)
{
	u32 interruptibility_old = vmcs_read32(GUEST_INTERRUPTIBILITY_INFO);
	u32 interruptibility = interruptibility_old;

	interruptibility &= ~(GUEST_INTR_STATE_STI | GUEST_INTR_STATE_MOV_SS);

	if (mask & KVM_X86_SHADOW_INT_MOV_SS)
		interruptibility |= GUEST_INTR_STATE_MOV_SS;
	else if (mask & KVM_X86_SHADOW_INT_STI)
		interruptibility |= GUEST_INTR_STATE_STI;

	if ((interruptibility != interruptibility_old))
		vmcs_write32(GUEST_INTERRUPTIBILITY_INFO, interruptibility);
}

static int vmx_rtit_ctl_check(struct kvm_vcpu *vcpu, u64 data)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	unsigned long value;

	/*
	 * Any MSR write that attempts to change bits marked reserved will
	 * case a #GP fault.
	 */
	if (data & vmx->pt_desc.ctl_bitmask)
		return 1;

	/*
	 * Any attempt to modify IA32_RTIT_CTL while TraceEn is set will
	 * result in a #GP unless the same write also clears TraceEn.
	 */
	if ((vmx->pt_desc.guest.ctl & RTIT_CTL_TRACEEN) &&
		((vmx->pt_desc.guest.ctl ^ data) & ~RTIT_CTL_TRACEEN))
		return 1;

	/*
	 * WRMSR to IA32_RTIT_CTL that sets TraceEn but clears this bit
	 * and FabricEn would cause #GP, if
	 * CPUID.(EAX=14H, ECX=0):ECX.SNGLRGNOUT[bit 2] = 0
	 */
	if ((data & RTIT_CTL_TRACEEN) && !(data & RTIT_CTL_TOPA) &&
		!(data & RTIT_CTL_FABRIC_EN) &&
		!intel_pt_validate_cap(vmx->pt_desc.caps,
					PT_CAP_single_range_output))
		return 1;

	/*
	 * MTCFreq, CycThresh and PSBFreq encodings check, any MSR write that
	 * utilize encodings marked reserved will cause a #GP fault.
	 */
	value = intel_pt_validate_cap(vmx->pt_desc.caps, PT_CAP_mtc_periods);
	if (intel_pt_validate_cap(vmx->pt_desc.caps, PT_CAP_mtc) &&
			!test_bit((data & RTIT_CTL_MTC_RANGE) >>
			RTIT_CTL_MTC_RANGE_OFFSET, &value))
		return 1;
	value = intel_pt_validate_cap(vmx->pt_desc.caps,
						PT_CAP_cycle_thresholds);
	if (intel_pt_validate_cap(vmx->pt_desc.caps, PT_CAP_psb_cyc) &&
			!test_bit((data & RTIT_CTL_CYC_THRESH) >>
			RTIT_CTL_CYC_THRESH_OFFSET, &value))
		return 1;
	value = intel_pt_validate_cap(vmx->pt_desc.caps, PT_CAP_psb_periods);
	if (intel_pt_validate_cap(vmx->pt_desc.caps, PT_CAP_psb_cyc) &&
			!test_bit((data & RTIT_CTL_PSB_FREQ) >>
			RTIT_CTL_PSB_FREQ_OFFSET, &value))
		return 1;

	/*
	 * If ADDRx_CFG is reserved or the encodings is >2 will
	 * cause a #GP fault.
	 */
	value = (data & RTIT_CTL_ADDR0) >> RTIT_CTL_ADDR0_OFFSET;
	if ((value && (vmx->pt_desc.num_address_ranges < 1)) || (value > 2))
		return 1;
	value = (data & RTIT_CTL_ADDR1) >> RTIT_CTL_ADDR1_OFFSET;
	if ((value && (vmx->pt_desc.num_address_ranges < 2)) || (value > 2))
		return 1;
	value = (data & RTIT_CTL_ADDR2) >> RTIT_CTL_ADDR2_OFFSET;
	if ((value && (vmx->pt_desc.num_address_ranges < 3)) || (value > 2))
		return 1;
	value = (data & RTIT_CTL_ADDR3) >> RTIT_CTL_ADDR3_OFFSET;
	if ((value && (vmx->pt_desc.num_address_ranges < 4)) || (value > 2))
		return 1;

	return 0;
}

static bool vmx_can_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type,
					void *insn, int insn_len)
{
	/*
	 * Emulation of instructions in SGX enclaves is impossible as RIP does
	 * not point at the failing instruction, and even if it did, the code
	 * stream is inaccessible.  Inject #UD instead of exiting to userspace
	 * so that guest userspace can't DoS the guest simply by triggering
	 * emulation (enclaves are CPL3 only).
	 */
	if (to_vmx(vcpu)->exit_reason.enclave_mode) {
		kvm_queue_exception(vcpu, UD_VECTOR);
		return false;
	}
	return true;
}

static int skip_emulated_instruction(struct kvm_vcpu *vcpu)
{
	union vmx_exit_reason exit_reason = to_vmx(vcpu)->exit_reason;
	unsigned long rip, orig_rip;
	u32 instr_len;

	/*
	 * Using VMCS.VM_EXIT_INSTRUCTION_LEN on EPT misconfig depends on
	 * undefined behavior: Intel's SDM doesn't mandate the VMCS field be
	 * set when EPT misconfig occurs.  In practice, real hardware updates
	 * VM_EXIT_INSTRUCTION_LEN on EPT misconfig, but other hypervisors
	 * (namely Hyper-V) don't set it due to it being undefined behavior,
	 * i.e. we end up advancing IP with some random value.
	 */
	if (!static_cpu_has(X86_FEATURE_HYPERVISOR) ||
	    exit_reason.basic != EXIT_REASON_EPT_MISCONFIG) {
		instr_len = vmcs_read32(VM_EXIT_INSTRUCTION_LEN);

		/*
		 * Emulating an enclave's instructions isn't supported as KVM
		 * cannot access the enclave's memory or its true RIP, e.g. the
		 * vmcs.GUEST_RIP points at the exit point of the enclave, not
		 * the RIP that actually triggered the VM-Exit.  But, because
		 * most instructions that cause VM-Exit will #UD in an enclave,
		 * most instruction-based VM-Exits simply do not occur.
		 *
		 * There are a few exceptions, notably the debug instructions
		 * INT1ICEBRK and INT3, as they are allowed in debug enclaves
		 * and generate #DB/#BP as expected, which KVM might intercept.
		 * But again, the CPU does the dirty work and saves an instr
		 * length of zero so VMMs don't shoot themselves in the foot.
		 * WARN if KVM tries to skip a non-zero length instruction on
		 * a VM-Exit from an enclave.
		 */
		if (!instr_len)
			goto rip_updated;

		WARN_ONCE(exit_reason.enclave_mode,
			  "skipping instruction after SGX enclave VM-Exit");

		orig_rip = kvm_rip_read(vcpu);
		rip = orig_rip + instr_len;
#ifdef CONFIG_X86_64
		/*
		 * We need to mask out the high 32 bits of RIP if not in 64-bit
		 * mode, but just finding out that we are in 64-bit mode is
		 * quite expensive.  Only do it if there was a carry.
		 */
		if (unlikely(((rip ^ orig_rip) >> 31) == 3) && !is_64_bit_mode(vcpu))
			rip = (u32)rip;
#endif
		kvm_rip_write(vcpu, rip);
	} else {
		if (!kvm_emulate_instruction(vcpu, EMULTYPE_SKIP))
			return 0;
	}

rip_updated:
	/* skipping an emulated instruction also counts */
	vmx_set_interrupt_shadow(vcpu, 0);

	return 1;
}

/*
 * Recognizes a pending MTF VM-exit and records the nested state for later
 * delivery.
 */
static void vmx_update_emulated_instruction(struct kvm_vcpu *vcpu)
{
	struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
	struct vcpu_vmx *vmx = to_vmx(vcpu);

	if (!is_guest_mode(vcpu))
		return;

	/*
	 * Per the SDM, MTF takes priority over debug-trap exceptions besides
	 * TSS T-bit traps and ICEBP (INT1).  KVM doesn't emulate T-bit traps
	 * or ICEBP (in the emulator proper), and skipping of ICEBP after an
	 * intercepted #DB deliberately avoids single-step #DB and MTF updates
	 * as ICEBP is higher priority than both.  As instruction emulation is
	 * completed at this point (i.e. KVM is at the instruction boundary),
	 * any #DB exception pending delivery must be a debug-trap of lower
	 * priority than MTF.  Record the pending MTF state to be delivered in
	 * vmx_check_nested_events().
	 */
	if (nested_cpu_has_mtf(vmcs12) &&
	    (!vcpu->arch.exception.pending ||
	     vcpu->arch.exception.vector == DB_VECTOR) &&
	    (!vcpu->arch.exception_vmexit.pending ||
	     vcpu->arch.exception_vmexit.vector == DB_VECTOR)) {
		vmx->nested.mtf_pending = true;
		kvm_make_request(KVM_REQ_EVENT, vcpu);
	} else {
		vmx->nested.mtf_pending = false;
	}
}

static int vmx_skip_emulated_instruction(struct kvm_vcpu *vcpu)
{
	vmx_update_emulated_instruction(vcpu);
	return skip_emulated_instruction(vcpu);
}

static void vmx_clear_hlt(struct kvm_vcpu *vcpu)
{
	/*
	 * Ensure that we clear the HLT state in the VMCS.  We don't need to
	 * explicitly skip the instruction because if the HLT state is set,
	 * then the instruction is already executing and RIP has already been
	 * advanced.
	 */
	if (kvm_hlt_in_guest(vcpu->kvm) &&
			vmcs_read32(GUEST_ACTIVITY_STATE) == GUEST_ACTIVITY_HLT)
		vmcs_write32(GUEST_ACTIVITY_STATE, GUEST_ACTIVITY_ACTIVE);
}

static void vmx_inject_exception(struct kvm_vcpu *vcpu)
{
	struct kvm_queued_exception *ex = &vcpu->arch.exception;
	u32 intr_info = ex->vector | INTR_INFO_VALID_MASK;
	struct vcpu_vmx *vmx = to_vmx(vcpu);

	kvm_deliver_exception_payload(vcpu, ex);

	if (ex->has_error_code) {
		/*
		 * Despite the error code being architecturally defined as 32
		 * bits, and the VMCS field being 32 bits, Intel CPUs and thus
		 * VMX don't actually supporting setting bits 31:16.  Hardware
		 * will (should) never provide a bogus error code, but AMD CPUs
		 * do generate error codes with bits 31:16 set, and so KVM's
		 * ABI lets userspace shove in arbitrary 32-bit values.  Drop
		 * the upper bits to avoid VM-Fail, losing information that
		 * does't really exist is preferable to killing the VM.
		 */
		vmcs_write32(VM_ENTRY_EXCEPTION_ERROR_CODE, (u16)ex->error_code);
		intr_info |= INTR_INFO_DELIVER_CODE_MASK;
	}

	if (vmx->rmode.vm86_active) {
		int inc_eip = 0;
		if (kvm_exception_is_soft(ex->vector))
			inc_eip = vcpu->arch.event_exit_inst_len;
		kvm_inject_realmode_interrupt(vcpu, ex->vector, inc_eip);
		return;
	}

	WARN_ON_ONCE(vmx->emulation_required);

	if (kvm_exception_is_soft(ex->vector)) {
		vmcs_write32(VM_ENTRY_INSTRUCTION_LEN,
			     vmx->vcpu.arch.event_exit_inst_len);
		intr_info |= INTR_TYPE_SOFT_EXCEPTION;
	} else
		intr_info |= INTR_TYPE_HARD_EXCEPTION;

	vmcs_write32(VM_ENTRY_INTR_INFO_FIELD, intr_info);

	vmx_clear_hlt(vcpu);
}

static void vmx_setup_uret_msr(struct vcpu_vmx *vmx, unsigned int msr,
			       bool load_into_hardware)
{
	struct vmx_uret_msr *uret_msr;

	uret_msr = vmx_find_uret_msr(vmx, msr);
	if (!uret_msr)
		return;

	uret_msr->load_into_hardware = load_into_hardware;
}

/*
 * Configuring user return MSRs to automatically save, load, and restore MSRs
 * that need to be shoved into hardware when running the guest.  Note, omitting
 * an MSR here does _NOT_ mean it's not emulated, only that it will not be
 * loaded into hardware when running the guest.
 */
static void vmx_setup_uret_msrs(struct vcpu_vmx *vmx)
{
#ifdef CONFIG_X86_64
	bool load_syscall_msrs;

	/*
	 * The SYSCALL MSRs are only needed on long mode guests, and only
	 * when EFER.SCE is set.
	 */
	load_syscall_msrs = is_long_mode(&vmx->vcpu) &&
			    (vmx->vcpu.arch.efer & EFER_SCE);

	vmx_setup_uret_msr(vmx, MSR_STAR, load_syscall_msrs);
	vmx_setup_uret_msr(vmx, MSR_LSTAR, load_syscall_msrs);
	vmx_setup_uret_msr(vmx, MSR_SYSCALL_MASK, load_syscall_msrs);
#endif
	vmx_setup_uret_msr(vmx, MSR_EFER, update_transition_efer(vmx));

	vmx_setup_uret_msr(vmx, MSR_TSC_AUX,
			   guest_cpuid_has(&vmx->vcpu, X86_FEATURE_RDTSCP) ||
			   guest_cpuid_has(&vmx->vcpu, X86_FEATURE_RDPID));

	/*
	 * hle=0, rtm=0, tsx_ctrl=1 can be found with some combinations of new
	 * kernel and old userspace.  If those guests run on a tsx=off host, do
	 * allow guests to use TSX_CTRL, but don't change the value in hardware
	 * so that TSX remains always disabled.
	 */
	vmx_setup_uret_msr(vmx, MSR_IA32_TSX_CTRL, boot_cpu_has(X86_FEATURE_RTM));

	/*
	 * The set of MSRs to load may have changed, reload MSRs before the
	 * next VM-Enter.
	 */
	vmx->guest_uret_msrs_loaded = false;
}

u64 vmx_get_l2_tsc_offset(struct kvm_vcpu *vcpu)
{
	struct vmcs12 *vmcs12 = get_vmcs12(vcpu);

	if (nested_cpu_has(vmcs12, CPU_BASED_USE_TSC_OFFSETTING))
		return vmcs12->tsc_offset;

	return 0;
}

u64 vmx_get_l2_tsc_multiplier(struct kvm_vcpu *vcpu)
{
	struct vmcs12 *vmcs12 = get_vmcs12(vcpu);

	if (nested_cpu_has(vmcs12, CPU_BASED_USE_TSC_OFFSETTING) &&
	    nested_cpu_has2(vmcs12, SECONDARY_EXEC_TSC_SCALING))
		return vmcs12->tsc_multiplier;

	return kvm_caps.default_tsc_scaling_ratio;
}

static void vmx_write_tsc_offset(struct kvm_vcpu *vcpu)
{
	vmcs_write64(TSC_OFFSET, vcpu->arch.tsc_offset);
}

static void vmx_write_tsc_multiplier(struct kvm_vcpu *vcpu)
{
	vmcs_write64(TSC_MULTIPLIER, vcpu->arch.tsc_scaling_ratio);
}

/*
 * Userspace is allowed to set any supported IA32_FEATURE_CONTROL regardless of
 * guest CPUID.  Note, KVM allows userspace to set "VMX in SMX" to maintain
 * backwards compatibility even though KVM doesn't support emulating SMX.  And
 * because userspace set "VMX in SMX", the guest must also be allowed to set it,
 * e.g. if the MSR is left unlocked and the guest does a RMW operation.
 */
#define KVM_SUPPORTED_FEATURE_CONTROL  (FEAT_CTL_LOCKED			 | \
					FEAT_CTL_VMX_ENABLED_INSIDE_SMX	 | \
					FEAT_CTL_VMX_ENABLED_OUTSIDE_SMX | \
					FEAT_CTL_SGX_LC_ENABLED		 | \
					FEAT_CTL_SGX_ENABLED		 | \
					FEAT_CTL_LMCE_ENABLED)

static inline bool is_vmx_feature_control_msr_valid(struct vcpu_vmx *vmx,
						    struct msr_data *msr)
{
	uint64_t valid_bits;

	/*
	 * Ensure KVM_SUPPORTED_FEATURE_CONTROL is updated when new bits are
	 * exposed to the guest.
	 */
	WARN_ON_ONCE(vmx->msr_ia32_feature_control_valid_bits &
		     ~KVM_SUPPORTED_FEATURE_CONTROL);

	if (!msr->host_initiated &&
	    (vmx->msr_ia32_feature_control & FEAT_CTL_LOCKED))
		return false;

	if (msr->host_initiated)
		valid_bits = KVM_SUPPORTED_FEATURE_CONTROL;
	else
		valid_bits = vmx->msr_ia32_feature_control_valid_bits;

	return !(msr->data & ~valid_bits);
}

static int vmx_get_msr_feature(struct kvm_msr_entry *msr)
{
	switch (msr->index) {
	case KVM_FIRST_EMULATED_VMX_MSR ... KVM_LAST_EMULATED_VMX_MSR:
		if (!nested)
			return 1;
		return vmx_get_vmx_msr(&vmcs_config.nested, msr->index, &msr->data);
	default:
		return KVM_MSR_RET_INVALID;
	}
}

/*
 * Reads an msr value (of 'msr_info->index') into 'msr_info->data'.
 * Returns 0 on success, non-0 otherwise.
 * Assumes vcpu_load() was already called.
 */
static int vmx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	struct vmx_uret_msr *msr;
	u32 index;

	switch (msr_info->index) {
#ifdef CONFIG_X86_64
	case MSR_FS_BASE:
		msr_info->data = vmcs_readl(GUEST_FS_BASE);
		break;
	case MSR_GS_BASE:
		msr_info->data = vmcs_readl(GUEST_GS_BASE);
		break;
	case MSR_KERNEL_GS_BASE:
		msr_info->data = vmx_read_guest_kernel_gs_base(vmx);
		break;
#endif
	case MSR_EFER:
		return kvm_get_msr_common(vcpu, msr_info);
	case MSR_IA32_TSX_CTRL:
		if (!msr_info->host_initiated &&
		    !(vcpu->arch.arch_capabilities & ARCH_CAP_TSX_CTRL_MSR))
			return 1;
		goto find_uret_msr;
	case MSR_IA32_UMWAIT_CONTROL:
		if (!msr_info->host_initiated && !vmx_has_waitpkg(vmx))
			return 1;

		msr_info->data = vmx->msr_ia32_umwait_control;
		break;
	case MSR_IA32_SPEC_CTRL:
		if (!msr_info->host_initiated &&
		    !guest_has_spec_ctrl_msr(vcpu))
			return 1;

		msr_info->data = to_vmx(vcpu)->spec_ctrl;
		break;
	case MSR_IA32_SYSENTER_CS:
		msr_info->data = vmcs_read32(GUEST_SYSENTER_CS);
		break;
	case MSR_IA32_SYSENTER_EIP:
		msr_info->data = vmcs_readl(GUEST_SYSENTER_EIP);
		break;
	case MSR_IA32_SYSENTER_ESP:
		msr_info->data = vmcs_readl(GUEST_SYSENTER_ESP);
		break;
	case MSR_IA32_BNDCFGS:
		if (!kvm_mpx_supported() ||
		    (!msr_info->host_initiated &&
		     !guest_cpuid_has(vcpu, X86_FEATURE_MPX)))
			return 1;
		msr_info->data = vmcs_read64(GUEST_BNDCFGS);
		break;
	case MSR_IA32_MCG_EXT_CTL:
		if (!msr_info->host_initiated &&
		    !(vmx->msr_ia32_feature_control &
		      FEAT_CTL_LMCE_ENABLED))
			return 1;
		msr_info->data = vcpu->arch.mcg_ext_ctl;
		break;
	case MSR_IA32_FEAT_CTL:
		msr_info->data = vmx->msr_ia32_feature_control;
		break;
	case MSR_IA32_SGXLEPUBKEYHASH0 ... MSR_IA32_SGXLEPUBKEYHASH3:
		if (!msr_info->host_initiated &&
		    !guest_cpuid_has(vcpu, X86_FEATURE_SGX_LC))
			return 1;
		msr_info->data = to_vmx(vcpu)->msr_ia32_sgxlepubkeyhash
			[msr_info->index - MSR_IA32_SGXLEPUBKEYHASH0];
		break;
	case KVM_FIRST_EMULATED_VMX_MSR ... KVM_LAST_EMULATED_VMX_MSR:
		if (!guest_can_use(vcpu, X86_FEATURE_VMX))
			return 1;
		if (vmx_get_vmx_msr(&vmx->nested.msrs, msr_info->index,
				    &msr_info->data))
			return 1;
		/*
		 * Enlightened VMCS v1 doesn't have certain VMCS fields but
		 * instead of just ignoring the features, different Hyper-V
		 * versions are either trying to use them and fail or do some
		 * sanity checking and refuse to boot. Filter all unsupported
		 * features out.
		 */
		if (!msr_info->host_initiated && guest_cpuid_has_evmcs(vcpu))
			nested_evmcs_filter_control_msr(vcpu, msr_info->index,
							&msr_info->data);
		break;
	case MSR_IA32_RTIT_CTL:
		if (!vmx_pt_mode_is_host_guest())
			return 1;
		msr_info->data = vmx->pt_desc.guest.ctl;
		break;
	case MSR_IA32_RTIT_STATUS:
		if (!vmx_pt_mode_is_host_guest())
			return 1;
		msr_info->data = vmx->pt_desc.guest.status;
		break;
	case MSR_IA32_RTIT_CR3_MATCH:
		if (!vmx_pt_mode_is_host_guest() ||
			!intel_pt_validate_cap(vmx->pt_desc.caps,
						PT_CAP_cr3_filtering))
			return 1;
		msr_info->data = vmx->pt_desc.guest.cr3_match;
		break;
	case MSR_IA32_RTIT_OUTPUT_BASE:
		if (!vmx_pt_mode_is_host_guest() ||
			(!intel_pt_validate_cap(vmx->pt_desc.caps,
					PT_CAP_topa_output) &&
			 !intel_pt_validate_cap(vmx->pt_desc.caps,
					PT_CAP_single_range_output)))
			return 1;
		msr_info->data = vmx->pt_desc.guest.output_base;
		break;
	case MSR_IA32_RTIT_OUTPUT_MASK:
		if (!vmx_pt_mode_is_host_guest() ||
			(!intel_pt_validate_cap(vmx->pt_desc.caps,
					PT_CAP_topa_output) &&
			 !intel_pt_validate_cap(vmx->pt_desc.caps,
					PT_CAP_single_range_output)))
			return 1;
		msr_info->data = vmx->pt_desc.guest.output_mask;
		break;
	case MSR_IA32_RTIT_ADDR0_A ... MSR_IA32_RTIT_ADDR3_B:
		index = msr_info->index - MSR_IA32_RTIT_ADDR0_A;
		if (!vmx_pt_mode_is_host_guest() ||
		    (index >= 2 * vmx->pt_desc.num_address_ranges))
			return 1;
		if (index % 2)
			msr_info->data = vmx->pt_desc.guest.addr_b[index / 2];
		else
			msr_info->data = vmx->pt_desc.guest.addr_a[index / 2];
		break;
	case MSR_IA32_DEBUGCTLMSR:
		msr_info->data = vmcs_read64(GUEST_IA32_DEBUGCTL);
		break;
	default:
	find_uret_msr:
		msr = vmx_find_uret_msr(vmx, msr_info->index);
		if (msr) {
			msr_info->data = msr->data;
			break;
		}
		return kvm_get_msr_common(vcpu, msr_info);
	}

	return 0;
}

static u64 nested_vmx_truncate_sysenter_addr(struct kvm_vcpu *vcpu,
						    u64 data)
{
#ifdef CONFIG_X86_64
	if (!guest_cpuid_has(vcpu, X86_FEATURE_LM))
		return (u32)data;
#endif
	return (unsigned long)data;
}

static u64 vmx_get_supported_debugctl(struct kvm_vcpu *vcpu, bool host_initiated)
{
	u64 debugctl = 0;

	if (boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT) &&
	    (host_initiated || guest_cpuid_has(vcpu, X86_FEATURE_BUS_LOCK_DETECT)))
		debugctl |= DEBUGCTLMSR_BUS_LOCK_DETECT;

	if ((kvm_caps.supported_perf_cap & PMU_CAP_LBR_FMT) &&
	    (host_initiated || intel_pmu_lbr_is_enabled(vcpu)))
		debugctl |= DEBUGCTLMSR_LBR | DEBUGCTLMSR_FREEZE_LBRS_ON_PMI;

	return debugctl;
}

/*
 * Writes msr value into the appropriate "register".
 * Returns 0 on success, non-0 otherwise.
 * Assumes vcpu_load() was already called.
 */
static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	struct vmx_uret_msr *msr;
	int ret = 0;
	u32 msr_index = msr_info->index;
	u64 data = msr_info->data;
	u32 index;

	switch (msr_index) {
	case MSR_EFER:
		ret = kvm_set_msr_common(vcpu, msr_info);
		break;
#ifdef CONFIG_X86_64
	case MSR_FS_BASE:
		vmx_segment_cache_clear(vmx);
		vmcs_writel(GUEST_FS_BASE, data);
		break;
	case MSR_GS_BASE:
		vmx_segment_cache_clear(vmx);
		vmcs_writel(GUEST_GS_BASE, data);
		break;
	case MSR_KERNEL_GS_BASE:
		vmx_write_guest_kernel_gs_base(vmx, data);
		break;
	case MSR_IA32_XFD:
		ret = kvm_set_msr_common(vcpu, msr_info);
		/*
		 * Always intercepting WRMSR could incur non-negligible
		 * overhead given xfd might be changed frequently in
		 * guest context switch. Disable write interception
		 * upon the first write with a non-zero value (indicating
		 * potential usage on dynamic xfeatures). Also update
		 * exception bitmap to trap #NM for proper virtualization
		 * of guest xfd_err.
		 */
		if (!ret && data) {
			vmx_disable_intercept_for_msr(vcpu, MSR_IA32_XFD,
						      MSR_TYPE_RW);
			vcpu->arch.xfd_no_write_intercept = true;
			vmx_update_exception_bitmap(vcpu);
		}
		break;
#endif
	case MSR_IA32_SYSENTER_CS:
		if (is_guest_mode(vcpu))
			get_vmcs12(vcpu)->guest_sysenter_cs = data;
		vmcs_write32(GUEST_SYSENTER_CS, data);
		break;
	case MSR_IA32_SYSENTER_EIP:
		if (is_guest_mode(vcpu)) {
			data = nested_vmx_truncate_sysenter_addr(vcpu, data);
			get_vmcs12(vcpu)->guest_sysenter_eip = data;
		}
		vmcs_writel(GUEST_SYSENTER_EIP, data);
		break;
	case MSR_IA32_SYSENTER_ESP:
		if (is_guest_mode(vcpu)) {
			data = nested_vmx_truncate_sysenter_addr(vcpu, data);
			get_vmcs12(vcpu)->guest_sysenter_esp = data;
		}
		vmcs_writel(GUEST_SYSENTER_ESP, data);
		break;
	case MSR_IA32_DEBUGCTLMSR: {
		u64 invalid;

		invalid = data & ~vmx_get_supported_debugctl(vcpu, msr_info->host_initiated);
		if (invalid & (DEBUGCTLMSR_BTF|DEBUGCTLMSR_LBR)) {
			kvm_pr_unimpl_wrmsr(vcpu, msr_index, data);
			data &= ~(DEBUGCTLMSR_BTF|DEBUGCTLMSR_LBR);
			invalid &= ~(DEBUGCTLMSR_BTF|DEBUGCTLMSR_LBR);
		}

		if (invalid)
			return 1;

		if (is_guest_mode(vcpu) && get_vmcs12(vcpu)->vm_exit_controls &
						VM_EXIT_SAVE_DEBUG_CONTROLS)
			get_vmcs12(vcpu)->guest_ia32_debugctl = data;

		vmcs_write64(GUEST_IA32_DEBUGCTL, data);
		if (intel_pmu_lbr_is_enabled(vcpu) && !to_vmx(vcpu)->lbr_desc.event &&
		    (data & DEBUGCTLMSR_LBR))
			intel_pmu_create_guest_lbr_event(vcpu);
		return 0;
	}
	case MSR_IA32_BNDCFGS:
		if (!kvm_mpx_supported() ||
		    (!msr_info->host_initiated &&
		     !guest_cpuid_has(vcpu, X86_FEATURE_MPX)))
			return 1;
		if (is_noncanonical_address(data & PAGE_MASK, vcpu) ||
		    (data & MSR_IA32_BNDCFGS_RSVD))
			return 1;

		if (is_guest_mode(vcpu) &&
		    ((vmx->nested.msrs.entry_ctls_high & VM_ENTRY_LOAD_BNDCFGS) ||
		     (vmx->nested.msrs.exit_ctls_high & VM_EXIT_CLEAR_BNDCFGS)))
			get_vmcs12(vcpu)->guest_bndcfgs = data;

		vmcs_write64(GUEST_BNDCFGS, data);
		break;
	case MSR_IA32_UMWAIT_CONTROL:
		if (!msr_info->host_initiated && !vmx_has_waitpkg(vmx))
			return 1;

		/* The reserved bit 1 and non-32 bit [63:32] should be zero */
		if (data & (BIT_ULL(1) | GENMASK_ULL(63, 32)))
			return 1;

		vmx->msr_ia32_umwait_control = data;
		break;
	case MSR_IA32_SPEC_CTRL:
		if (!msr_info->host_initiated &&
		    !guest_has_spec_ctrl_msr(vcpu))
			return 1;

		if (kvm_spec_ctrl_test_value(data))
			return 1;

		vmx->spec_ctrl = data;
		if (!data)
			break;

		/*
		 * For non-nested:
		 * When it's written (to non-zero) for the first time, pass
		 * it through.
		 *
		 * For nested:
		 * The handling of the MSR bitmap for L2 guests is done in
		 * nested_vmx_prepare_msr_bitmap. We should not touch the
		 * vmcs02.msr_bitmap here since it gets completely overwritten
		 * in the merging. We update the vmcs01 here for L1 as well
		 * since it will end up touching the MSR anyway now.
		 */
		vmx_disable_intercept_for_msr(vcpu,
					      MSR_IA32_SPEC_CTRL,
					      MSR_TYPE_RW);
		break;
	case MSR_IA32_TSX_CTRL:
		if (!msr_info->host_initiated &&
		    !(vcpu->arch.arch_capabilities & ARCH_CAP_TSX_CTRL_MSR))
			return 1;
		if (data & ~(TSX_CTRL_RTM_DISABLE | TSX_CTRL_CPUID_CLEAR))
			return 1;
		goto find_uret_msr;
	case MSR_IA32_CR_PAT:
		ret = kvm_set_msr_common(vcpu, msr_info);
		if (ret)
			break;

		if (is_guest_mode(vcpu) &&
		    get_vmcs12(vcpu)->vm_exit_controls & VM_EXIT_SAVE_IA32_PAT)
			get_vmcs12(vcpu)->guest_ia32_pat = data;

		if (vmcs_config.vmentry_ctrl & VM_ENTRY_LOAD_IA32_PAT)
			vmcs_write64(GUEST_IA32_PAT, data);
		break;
	case MSR_IA32_MCG_EXT_CTL:
		if ((!msr_info->host_initiated &&
		     !(to_vmx(vcpu)->msr_ia32_feature_control &
		       FEAT_CTL_LMCE_ENABLED)) ||
		    (data & ~MCG_EXT_CTL_LMCE_EN))
			return 1;
		vcpu->arch.mcg_ext_ctl = data;
		break;
	case MSR_IA32_FEAT_CTL:
		if (!is_vmx_feature_control_msr_valid(vmx, msr_info))
			return 1;

		vmx->msr_ia32_feature_control = data;
		if (msr_info->host_initiated && data == 0)
			vmx_leave_nested(vcpu);

		/* SGX may be enabled/disabled by guest's firmware */
		vmx_write_encls_bitmap(vcpu, NULL);
		break;
	case MSR_IA32_SGXLEPUBKEYHASH0 ... MSR_IA32_SGXLEPUBKEYHASH3:
		/*
		 * On real hardware, the LE hash MSRs are writable before
		 * the firmware sets bit 0 in MSR 0x7a ("activating" SGX),
		 * at which point SGX related bits in IA32_FEATURE_CONTROL
		 * become writable.
		 *
		 * KVM does not emulate SGX activation for simplicity, so
		 * allow writes to the LE hash MSRs if IA32_FEATURE_CONTROL
		 * is unlocked.  This is technically not architectural
		 * behavior, but it's close enough.
		 */
		if (!msr_info->host_initiated &&
		    (!guest_cpuid_has(vcpu, X86_FEATURE_SGX_LC) ||
		    ((vmx->msr_ia32_feature_control & FEAT_CTL_LOCKED) &&
		    !(vmx->msr_ia32_feature_control & FEAT_CTL_SGX_LC_ENABLED))))
			return 1;
		vmx->msr_ia32_sgxlepubkeyhash
			[msr_index - MSR_IA32_SGXLEPUBKEYHASH0] = data;
		break;
	case KVM_FIRST_EMULATED_VMX_MSR ... KVM_LAST_EMULATED_VMX_MSR:
		if (!msr_info->host_initiated)
			return 1; /* they are read-only */
		if (!guest_can_use(vcpu, X86_FEATURE_VMX))
			return 1;
		return vmx_set_vmx_msr(vcpu, msr_index, data);
	case MSR_IA32_RTIT_CTL:
		if (!vmx_pt_mode_is_host_guest() ||
			vmx_rtit_ctl_check(vcpu, data) ||
			vmx->nested.vmxon)
			return 1;
		vmcs_write64(GUEST_IA32_RTIT_CTL, data);
		vmx->pt_desc.guest.ctl = data;
		pt_update_intercept_for_msr(vcpu);
		break;
	case MSR_IA32_RTIT_STATUS:
		if (!pt_can_write_msr(vmx))
			return 1;
		if (data & MSR_IA32_RTIT_STATUS_MASK)
			return 1;
		vmx->pt_desc.guest.status = data;
		break;
	case MSR_IA32_RTIT_CR3_MATCH:
		if (!pt_can_write_msr(vmx))
			return 1;
		if (!intel_pt_validate_cap(vmx->pt_desc.caps,
					   PT_CAP_cr3_filtering))
			return 1;
		vmx->pt_desc.guest.cr3_match = data;
		break;
	case MSR_IA32_RTIT_OUTPUT_BASE:
		if (!pt_can_write_msr(vmx))
			return 1;
		if (!intel_pt_validate_cap(vmx->pt_desc.caps,
					   PT_CAP_topa_output) &&
		    !intel_pt_validate_cap(vmx->pt_desc.caps,
					   PT_CAP_single_range_output))
			return 1;
		if (!pt_output_base_valid(vcpu, data))
			return 1;
		vmx->pt_desc.guest.output_base = data;
		break;
	case MSR_IA32_RTIT_OUTPUT_MASK:
		if (!pt_can_write_msr(vmx))
			return 1;
		if (!intel_pt_validate_cap(vmx->pt_desc.caps,
					   PT_CAP_topa_output) &&
		    !intel_pt_validate_cap(vmx->pt_desc.caps,
					   PT_CAP_single_range_output))
			return 1;
		vmx->pt_desc.guest.output_mask = data;
		break;
	case MSR_IA32_RTIT_ADDR0_A ... MSR_IA32_RTIT_ADDR3_B:
		if (!pt_can_write_msr(vmx))
			return 1;
		index = msr_info->index - MSR_IA32_RTIT_ADDR0_A;
		if (index >= 2 * vmx->pt_desc.num_address_ranges)
			return 1;
		if (is_noncanonical_address(data, vcpu))
			return 1;
		if (index % 2)
			vmx->pt_desc.guest.addr_b[index / 2] = data;
		else
			vmx->pt_desc.guest.addr_a[index / 2] = data;
		break;
	case MSR_IA32_PERF_CAPABILITIES:
		if (data && !vcpu_to_pmu(vcpu)->version)
			return 1;
		if (data & PMU_CAP_LBR_FMT) {
			if ((data & PMU_CAP_LBR_FMT) !=
			    (kvm_caps.supported_perf_cap & PMU_CAP_LBR_FMT))
				return 1;
			if (!cpuid_model_is_consistent(vcpu))
				return 1;
		}
		if (data & PERF_CAP_PEBS_FORMAT) {
			if ((data & PERF_CAP_PEBS_MASK) !=
			    (kvm_caps.supported_perf_cap & PERF_CAP_PEBS_MASK))
				return 1;
			if (!guest_cpuid_has(vcpu, X86_FEATURE_DS))
				return 1;
			if (!guest_cpuid_has(vcpu, X86_FEATURE_DTES64))
				return 1;
			if (!cpuid_model_is_consistent(vcpu))
				return 1;
		}
		ret = kvm_set_msr_common(vcpu, msr_info);
		break;

	default:
	find_uret_msr:
		msr = vmx_find_uret_msr(vmx, msr_index);
		if (msr)
			ret = vmx_set_guest_uret_msr(vmx, msr, data);
		else
			ret = kvm_set_msr_common(vcpu, msr_info);
	}

	/* FB_CLEAR may have changed, also update the FB_CLEAR_DIS behavior */
	if (msr_index == MSR_IA32_ARCH_CAPABILITIES)
		vmx_update_fb_clear_dis(vcpu, vmx);

	return ret;
}

static void vmx_cache_reg(struct kvm_vcpu *vcpu, enum kvm_reg reg)
{
	unsigned long guest_owned_bits;

	kvm_register_mark_available(vcpu, reg);

	switch (reg) {
	case VCPU_REGS_RSP:
		vcpu->arch.regs[VCPU_REGS_RSP] = vmcs_readl(GUEST_RSP);
		break;
	case VCPU_REGS_RIP:
		vcpu->arch.regs[VCPU_REGS_RIP] = vmcs_readl(GUEST_RIP);
		break;
	case VCPU_EXREG_PDPTR:
		if (enable_ept)
			ept_save_pdptrs(vcpu);
		break;
	case VCPU_EXREG_CR0:
		guest_owned_bits = vcpu->arch.cr0_guest_owned_bits;

		vcpu->arch.cr0 &= ~guest_owned_bits;
		vcpu->arch.cr0 |= vmcs_readl(GUEST_CR0) & guest_owned_bits;
		break;
	case VCPU_EXREG_CR3:
		/*
		 * When intercepting CR3 loads, e.g. for shadowing paging, KVM's
		 * CR3 is loaded into hardware, not the guest's CR3.
		 */
		if (!(exec_controls_get(to_vmx(vcpu)) & CPU_BASED_CR3_LOAD_EXITING))
			vcpu->arch.cr3 = vmcs_readl(GUEST_CR3);
		break;
	case VCPU_EXREG_CR4:
		guest_owned_bits = vcpu->arch.cr4_guest_owned_bits;

		vcpu->arch.cr4 &= ~guest_owned_bits;
		vcpu->arch.cr4 |= vmcs_readl(GUEST_CR4) & guest_owned_bits;
		break;
	default:
		KVM_BUG_ON(1, vcpu->kvm);
		break;
	}
}

/*
 * There is no X86_FEATURE for SGX yet, but anyway we need to query CPUID
 * directly instead of going through cpu_has(), to ensure KVM is trapping
 * ENCLS whenever it's supported in hardware.  It does not matter whether
 * the host OS supports or has enabled SGX.
 */
static bool cpu_has_sgx(void)
{
	return cpuid_eax(0) >= 0x12 && (cpuid_eax(0x12) & BIT(0));
}

/*
 * Some cpus support VM_{ENTRY,EXIT}_IA32_PERF_GLOBAL_CTRL but they
 * can't be used due to errata where VM Exit may incorrectly clear
 * IA32_PERF_GLOBAL_CTRL[34:32]. Work around the errata by using the
 * MSR load mechanism to switch IA32_PERF_GLOBAL_CTRL.
 */
static bool cpu_has_perf_global_ctrl_bug(void)
{
	if (boot_cpu_data.x86 == 0x6) {
		switch (boot_cpu_data.x86_model) {
		case INTEL_FAM6_NEHALEM_EP:	/* AAK155 */
		case INTEL_FAM6_NEHALEM:	/* AAP115 */
		case INTEL_FAM6_WESTMERE:	/* AAT100 */
		case INTEL_FAM6_WESTMERE_EP:	/* BC86,AAY89,BD102 */
		case INTEL_FAM6_NEHALEM_EX:	/* BA97 */
			return true;
		default:
			break;
		}
	}

	return false;
}

static int adjust_vmx_controls(u32 ctl_min, u32 ctl_opt, u32 msr, u32 *result)
{
	u32 vmx_msr_low, vmx_msr_high;
	u32 ctl = ctl_min | ctl_opt;

	rdmsr(msr, vmx_msr_low, vmx_msr_high);

	ctl &= vmx_msr_high; /* bit == 0 in high word ==> must be zero */
	ctl |= vmx_msr_low;  /* bit == 1 in low word  ==> must be one  */

	/* Ensure minimum (required) set of control bits are supported. */
	if (ctl_min & ~ctl)
		return -EIO;

	*result = ctl;
	return 0;
}

static u64 adjust_vmx_controls64(u64 ctl_opt, u32 msr)
{
	u64 allowed;

	rdmsrl(msr, allowed);

	return  ctl_opt & allowed;
}

static int setup_vmcs_config(struct vmcs_config *vmcs_conf,
			     struct vmx_capability *vmx_cap)
{
	u32 vmx_msr_low, vmx_msr_high;
	u32 _pin_based_exec_control = 0;
	u32 _cpu_based_exec_control = 0;
	u32 _cpu_based_2nd_exec_control = 0;
	u64 _cpu_based_3rd_exec_control = 0;
	u32 _vmexit_control = 0;
	u32 _vmentry_control = 0;
	u64 misc_msr;
	int i;

	/*
	 * LOAD/SAVE_DEBUG_CONTROLS are absent because both are mandatory.
	 * SAVE_IA32_PAT and SAVE_IA32_EFER are absent because KVM always
	 * intercepts writes to PAT and EFER, i.e. never enables those controls.
	 */
	struct {
		u32 entry_control;
		u32 exit_control;
	} const vmcs_entry_exit_pairs[] = {
		{ VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL,	VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL },
		{ VM_ENTRY_LOAD_IA32_PAT,		VM_EXIT_LOAD_IA32_PAT },
		{ VM_ENTRY_LOAD_IA32_EFER,		VM_EXIT_LOAD_IA32_EFER },
		{ VM_ENTRY_LOAD_BNDCFGS,		VM_EXIT_CLEAR_BNDCFGS },
		{ VM_ENTRY_LOAD_IA32_RTIT_CTL,		VM_EXIT_CLEAR_IA32_RTIT_CTL },
	};

	memset(vmcs_conf, 0, sizeof(*vmcs_conf));

	if (adjust_vmx_controls(KVM_REQUIRED_VMX_CPU_BASED_VM_EXEC_CONTROL,
				KVM_OPTIONAL_VMX_CPU_BASED_VM_EXEC_CONTROL,
				MSR_IA32_VMX_PROCBASED_CTLS,
				&_cpu_based_exec_control))
		return -EIO;
	if (_cpu_based_exec_control & CPU_BASED_ACTIVATE_SECONDARY_CONTROLS) {
		if (adjust_vmx_controls(KVM_REQUIRED_VMX_SECONDARY_VM_EXEC_CONTROL,
					KVM_OPTIONAL_VMX_SECONDARY_VM_EXEC_CONTROL,
					MSR_IA32_VMX_PROCBASED_CTLS2,
					&_cpu_based_2nd_exec_control))
			return -EIO;
	}
#ifndef CONFIG_X86_64
	if (!(_cpu_based_2nd_exec_control &
				SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES))
		_cpu_based_exec_control &= ~CPU_BASED_TPR_SHADOW;
#endif

	if (!(_cpu_based_exec_control & CPU_BASED_TPR_SHADOW))
		_cpu_based_2nd_exec_control &= ~(
				SECONDARY_EXEC_APIC_REGISTER_VIRT |
				SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE |
				SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY);

	rdmsr_safe(MSR_IA32_VMX_EPT_VPID_CAP,
		&vmx_cap->ept, &vmx_cap->vpid);

	if (!(_cpu_based_2nd_exec_control & SECONDARY_EXEC_ENABLE_EPT) &&
	    vmx_cap->ept) {
		pr_warn_once("EPT CAP should not exist if not support "
				"1-setting enable EPT VM-execution control\n");

		if (error_on_inconsistent_vmcs_config)
			return -EIO;

		vmx_cap->ept = 0;
	}
	if (!(_cpu_based_2nd_exec_control & SECONDARY_EXEC_ENABLE_VPID) &&
	    vmx_cap->vpid) {
		pr_warn_once("VPID CAP should not exist if not support "
				"1-setting enable VPID VM-execution control\n");

		if (error_on_inconsistent_vmcs_config)
			return -EIO;

		vmx_cap->vpid = 0;
	}

	if (!cpu_has_sgx())
		_cpu_based_2nd_exec_control &= ~SECONDARY_EXEC_ENCLS_EXITING;

	if (_cpu_based_exec_control & CPU_BASED_ACTIVATE_TERTIARY_CONTROLS)
		_cpu_based_3rd_exec_control =
			adjust_vmx_controls64(KVM_OPTIONAL_VMX_TERTIARY_VM_EXEC_CONTROL,
					      MSR_IA32_VMX_PROCBASED_CTLS3);

	if (adjust_vmx_controls(KVM_REQUIRED_VMX_VM_EXIT_CONTROLS,
				KVM_OPTIONAL_VMX_VM_EXIT_CONTROLS,
				MSR_IA32_VMX_EXIT_CTLS,
				&_vmexit_control))
		return -EIO;

	if (adjust_vmx_controls(KVM_REQUIRED_VMX_PIN_BASED_VM_EXEC_CONTROL,
				KVM_OPTIONAL_VMX_PIN_BASED_VM_EXEC_CONTROL,
				MSR_IA32_VMX_PINBASED_CTLS,
				&_pin_based_exec_control))
		return -EIO;

	if (cpu_has_broken_vmx_preemption_timer())
		_pin_based_exec_control &= ~PIN_BASED_VMX_PREEMPTION_TIMER;
	if (!(_cpu_based_2nd_exec_control &
		SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY))
		_pin_based_exec_control &= ~PIN_BASED_POSTED_INTR;

	if (adjust_vmx_controls(KVM_REQUIRED_VMX_VM_ENTRY_CONTROLS,
				KVM_OPTIONAL_VMX_VM_ENTRY_CONTROLS,
				MSR_IA32_VMX_ENTRY_CTLS,
				&_vmentry_control))
		return -EIO;

	for (i = 0; i < ARRAY_SIZE(vmcs_entry_exit_pairs); i++) {
		u32 n_ctrl = vmcs_entry_exit_pairs[i].entry_control;
		u32 x_ctrl = vmcs_entry_exit_pairs[i].exit_control;

		if (!(_vmentry_control & n_ctrl) == !(_vmexit_control & x_ctrl))
			continue;

		pr_warn_once("Inconsistent VM-Entry/VM-Exit pair, entry = %x, exit = %x\n",
			     _vmentry_control & n_ctrl, _vmexit_control & x_ctrl);

		if (error_on_inconsistent_vmcs_config)
			return -EIO;

		_vmentry_control &= ~n_ctrl;
		_vmexit_control &= ~x_ctrl;
	}

	rdmsr(MSR_IA32_VMX_BASIC, vmx_msr_low, vmx_msr_high);

	/* IA-32 SDM Vol 3B: VMCS size is never greater than 4kB. */
	if ((vmx_msr_high & 0x1fff) > PAGE_SIZE)
		return -EIO;

#ifdef CONFIG_X86_64
	/* IA-32 SDM Vol 3B: 64-bit CPUs always have VMX_BASIC_MSR[48]==0. */
	if (vmx_msr_high & (1u<<16))
		return -EIO;
#endif

	/* Require Write-Back (WB) memory type for VMCS accesses. */
	if (((vmx_msr_high >> 18) & 15) != 6)
		return -EIO;

	rdmsrl(MSR_IA32_VMX_MISC, misc_msr);

	vmcs_conf->size = vmx_msr_high & 0x1fff;
	vmcs_conf->basic_cap = vmx_msr_high & ~0x1fff;

	vmcs_conf->revision_id = vmx_msr_low;

	vmcs_conf->pin_based_exec_ctrl = _pin_based_exec_control;
	vmcs_conf->cpu_based_exec_ctrl = _cpu_based_exec_control;
	vmcs_conf->cpu_based_2nd_exec_ctrl = _cpu_based_2nd_exec_control;
	vmcs_conf->cpu_based_3rd_exec_ctrl = _cpu_based_3rd_exec_control;
	vmcs_conf->vmexit_ctrl         = _vmexit_control;
	vmcs_conf->vmentry_ctrl        = _vmentry_control;
	vmcs_conf->misc	= misc_msr;

#if IS_ENABLED(CONFIG_HYPERV)
	if (enlightened_vmcs)
		evmcs_sanitize_exec_ctrls(vmcs_conf);
#endif

	return 0;
}

static bool __kvm_is_vmx_supported(void)
{
	int cpu = smp_processor_id();

	if (!(cpuid_ecx(1) & feature_bit(VMX))) {
		pr_err("VMX not supported by CPU %d\n", cpu);
		return false;
	}

	if (!this_cpu_has(X86_FEATURE_MSR_IA32_FEAT_CTL) ||
	    !this_cpu_has(X86_FEATURE_VMX)) {
		pr_err("VMX not enabled (by BIOS) in MSR_IA32_FEAT_CTL on CPU %d\n", cpu);
		return false;
	}

	return true;
}

static bool kvm_is_vmx_supported(void)
{
	bool supported;

	migrate_disable();
	supported = __kvm_is_vmx_supported();
	migrate_enable();

	return supported;
}

static int vmx_check_processor_compat(void)
{
	int cpu = raw_smp_processor_id();
	struct vmcs_config vmcs_conf;
	struct vmx_capability vmx_cap;

	if (!__kvm_is_vmx_supported())
		return -EIO;

	if (setup_vmcs_config(&vmcs_conf, &vmx_cap) < 0) {
		pr_err("Failed to setup VMCS config on CPU %d\n", cpu);
		return -EIO;
	}
	if (nested)
		nested_vmx_setup_ctls_msrs(&vmcs_conf, vmx_cap.ept);
	if (memcmp(&vmcs_config, &vmcs_conf, sizeof(struct vmcs_config))) {
		pr_err("Inconsistent VMCS config on CPU %d\n", cpu);
		return -EIO;
	}
	return 0;
}

static int kvm_cpu_vmxon(u64 vmxon_pointer)
{
	u64 msr;

	cr4_set_bits(X86_CR4_VMXE);

	asm_volatile_goto("1: vmxon %[vmxon_pointer]\n\t"
			  _ASM_EXTABLE(1b, %l[fault])
			  : : [vmxon_pointer] "m"(vmxon_pointer)
			  : : fault);
	return 0;

fault:
	WARN_ONCE(1, "VMXON faulted, MSR_IA32_FEAT_CTL (0x3a) = 0x%llx\n",
		  rdmsrl_safe(MSR_IA32_FEAT_CTL, &msr) ? 0xdeadbeef : msr);
	cr4_clear_bits(X86_CR4_VMXE);

	return -EFAULT;
}

static int vmx_hardware_enable(void)
{
	int cpu = raw_smp_processor_id();
	u64 phys_addr = __pa(per_cpu(vmxarea, cpu));
	int r;

	if (cr4_read_shadow() & X86_CR4_VMXE)
		return -EBUSY;

	/*
	 * This can happen if we hot-added a CPU but failed to allocate
	 * VP assist page for it.
	 */
	if (kvm_is_using_evmcs() && !hv_get_vp_assist_page(cpu))
		return -EFAULT;

	intel_pt_handle_vmx(1);

	r = kvm_cpu_vmxon(phys_addr);
	if (r) {
		intel_pt_handle_vmx(0);
		return r;
	}

	if (enable_ept)
		ept_sync_global();

	return 0;
}

static void vmclear_local_loaded_vmcss(void)
{
	int cpu = raw_smp_processor_id();
	struct loaded_vmcs *v, *n;

	list_for_each_entry_safe(v, n, &per_cpu(loaded_vmcss_on_cpu, cpu),
				 loaded_vmcss_on_cpu_link)
		__loaded_vmcs_clear(v);
}

static void vmx_hardware_disable(void)
{
	vmclear_local_loaded_vmcss();

	if (kvm_cpu_vmxoff())
		kvm_spurious_fault();

	hv_reset_evmcs();

	intel_pt_handle_vmx(0);
}

struct vmcs *alloc_vmcs_cpu(bool shadow, int cpu, gfp_t flags)
{
	int node = cpu_to_node(cpu);
	struct page *pages;
	struct vmcs *vmcs;

	pages = __alloc_pages_node(node, flags, 0);
	if (!pages)
		return NULL;
	vmcs = page_address(pages);
	memset(vmcs, 0, vmcs_config.size);

	/* KVM supports Enlightened VMCS v1 only */
	if (kvm_is_using_evmcs())
		vmcs->hdr.revision_id = KVM_EVMCS_VERSION;
	else
		vmcs->hdr.revision_id = vmcs_config.revision_id;

	if (shadow)
		vmcs->hdr.shadow_vmcs = 1;
	return vmcs;
}

void free_vmcs(struct vmcs *vmcs)
{
	free_page((unsigned long)vmcs);
}

/*
 * Free a VMCS, but before that VMCLEAR it on the CPU where it was last loaded
 */
void free_loaded_vmcs(struct loaded_vmcs *loaded_vmcs)
{
	if (!loaded_vmcs->vmcs)
		return;
	loaded_vmcs_clear(loaded_vmcs);
	free_vmcs(loaded_vmcs->vmcs);
	loaded_vmcs->vmcs = NULL;
	if (loaded_vmcs->msr_bitmap)
		free_page((unsigned long)loaded_vmcs->msr_bitmap);
	WARN_ON(loaded_vmcs->shadow_vmcs != NULL);
}

int alloc_loaded_vmcs(struct loaded_vmcs *loaded_vmcs)
{
	loaded_vmcs->vmcs = alloc_vmcs(false);
	if (!loaded_vmcs->vmcs)
		return -ENOMEM;

	vmcs_clear(loaded_vmcs->vmcs);

	loaded_vmcs->shadow_vmcs = NULL;
	loaded_vmcs->hv_timer_soft_disabled = false;
	loaded_vmcs->cpu = -1;
	loaded_vmcs->launched = 0;

	if (cpu_has_vmx_msr_bitmap()) {
		loaded_vmcs->msr_bitmap = (unsigned long *)
				__get_free_page(GFP_KERNEL_ACCOUNT);
		if (!loaded_vmcs->msr_bitmap)
			goto out_vmcs;
		memset(loaded_vmcs->msr_bitmap, 0xff, PAGE_SIZE);
	}

	memset(&loaded_vmcs->host_state, 0, sizeof(struct vmcs_host_state));
	memset(&loaded_vmcs->controls_shadow, 0,
		sizeof(struct vmcs_controls_shadow));

	return 0;

out_vmcs:
	free_loaded_vmcs(loaded_vmcs);
	return -ENOMEM;
}

static void free_kvm_area(void)
{
	int cpu;

	for_each_possible_cpu(cpu) {
		free_vmcs(per_cpu(vmxarea, cpu));
		per_cpu(vmxarea, cpu) = NULL;
	}
}

static __init int alloc_kvm_area(void)
{
	int cpu;

	for_each_possible_cpu(cpu) {
		struct vmcs *vmcs;

		vmcs = alloc_vmcs_cpu(false, cpu, GFP_KERNEL);
		if (!vmcs) {
			free_kvm_area();
			return -ENOMEM;
		}

		/*
		 * When eVMCS is enabled, alloc_vmcs_cpu() sets
		 * vmcs->revision_id to KVM_EVMCS_VERSION instead of
		 * revision_id reported by MSR_IA32_VMX_BASIC.
		 *
		 * However, even though not explicitly documented by
		 * TLFS, VMXArea passed as VMXON argument should
		 * still be marked with revision_id reported by
		 * physical CPU.
		 */
		if (kvm_is_using_evmcs())
			vmcs->hdr.revision_id = vmcs_config.revision_id;

		per_cpu(vmxarea, cpu) = vmcs;
	}
	return 0;
}

static void fix_pmode_seg(struct kvm_vcpu *vcpu, int seg,
		struct kvm_segment *save)
{
	if (!emulate_invalid_guest_state) {
		/*
		 * CS and SS RPL should be equal during guest entry according
		 * to VMX spec, but in reality it is not always so. Since vcpu
		 * is in the middle of the transition from real mode to
		 * protected mode it is safe to assume that RPL 0 is a good
		 * default value.
		 */
		if (seg == VCPU_SREG_CS || seg == VCPU_SREG_SS)
			save->selector &= ~SEGMENT_RPL_MASK;
		save->dpl = save->selector & SEGMENT_RPL_MASK;
		save->s = 1;
	}
	__vmx_set_segment(vcpu, save, seg);
}

static void enter_pmode(struct kvm_vcpu *vcpu)
{
	unsigned long flags;
	struct vcpu_vmx *vmx = to_vmx(vcpu);

	/*
	 * Update real mode segment cache. It may be not up-to-date if segment
	 * register was written while vcpu was in a guest mode.
	 */
	vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_ES], VCPU_SREG_ES);
	vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_DS], VCPU_SREG_DS);
	vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_FS], VCPU_SREG_FS);
	vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_GS], VCPU_SREG_GS);
	vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_SS], VCPU_SREG_SS);
	vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_CS], VCPU_SREG_CS);

	vmx->rmode.vm86_active = 0;

	__vmx_set_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_TR], VCPU_SREG_TR);

	flags = vmcs_readl(GUEST_RFLAGS);
	flags &= RMODE_GUEST_OWNED_EFLAGS_BITS;
	flags |= vmx->rmode.save_rflags & ~RMODE_GUEST_OWNED_EFLAGS_BITS;
	vmcs_writel(GUEST_RFLAGS, flags);

	vmcs_writel(GUEST_CR4, (vmcs_readl(GUEST_CR4) & ~X86_CR4_VME) |
			(vmcs_readl(CR4_READ_SHADOW) & X86_CR4_VME));

	vmx_update_exception_bitmap(vcpu);

	fix_pmode_seg(vcpu, VCPU_SREG_CS, &vmx->rmode.segs[VCPU_SREG_CS]);
	fix_pmode_seg(vcpu, VCPU_SREG_SS, &vmx->rmode.segs[VCPU_SREG_SS]);
	fix_pmode_seg(vcpu, VCPU_SREG_ES, &vmx->rmode.segs[VCPU_SREG_ES]);
	fix_pmode_seg(vcpu, VCPU_SREG_DS, &vmx->rmode.segs[VCPU_SREG_DS]);
	fix_pmode_seg(vcpu, VCPU_SREG_FS, &vmx->rmode.segs[VCPU_SREG_FS]);
	fix_pmode_seg(vcpu, VCPU_SREG_GS, &vmx->rmode.segs[VCPU_SREG_GS]);
}

static void fix_rmode_seg(int seg, struct kvm_segment *save)
{
	const struct kvm_vmx_segment_field *sf = &kvm_vmx_segment_fields[seg];
	struct kvm_segment var = *save;

	var.dpl = 0x3;
	if (seg == VCPU_SREG_CS)
		var.type = 0x3;

	if (!emulate_invalid_guest_state) {
		var.selector = var.base >> 4;
		var.base = var.base & 0xffff0;
		var.limit = 0xffff;
		var.g = 0;
		var.db = 0;
		var.present = 1;
		var.s = 1;
		var.l = 0;
		var.unusable = 0;
		var.type = 0x3;
		var.avl = 0;
		if (save->base & 0xf)
			pr_warn_once("segment base is not paragraph aligned "
				     "when entering protected mode (seg=%d)", seg);
	}

	vmcs_write16(sf->selector, var.selector);
	vmcs_writel(sf->base, var.base);
	vmcs_write32(sf->limit, var.limit);
	vmcs_write32(sf->ar_bytes, vmx_segment_access_rights(&var));
}

static void enter_rmode(struct kvm_vcpu *vcpu)
{
	unsigned long flags;
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	struct kvm_vmx *kvm_vmx = to_kvm_vmx(vcpu->kvm);

	/*
	 * KVM should never use VM86 to virtualize Real Mode when L2 is active,
	 * as using VM86 is unnecessary if unrestricted guest is enabled, and
	 * if unrestricted guest is disabled, VM-Enter (from L1) with CR0.PG=0
	 * should VM-Fail and KVM should reject userspace attempts to stuff
	 * CR0.PG=0 when L2 is active.
	 */
	WARN_ON_ONCE(is_guest_mode(vcpu));

	vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_TR], VCPU_SREG_TR);
	vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_ES], VCPU_SREG_ES);
	vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_DS], VCPU_SREG_DS);
	vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_FS], VCPU_SREG_FS);
	vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_GS], VCPU_SREG_GS);
	vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_SS], VCPU_SREG_SS);
	vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_CS], VCPU_SREG_CS);

	vmx->rmode.vm86_active = 1;

	vmx_segment_cache_clear(vmx);

	vmcs_writel(GUEST_TR_BASE, kvm_vmx->tss_addr);
	vmcs_write32(GUEST_TR_LIMIT, RMODE_TSS_SIZE - 1);
	vmcs_write32(GUEST_TR_AR_BYTES, 0x008b);

	flags = vmcs_readl(GUEST_RFLAGS);
	vmx->rmode.save_rflags = flags;

	flags |= X86_EFLAGS_IOPL | X86_EFLAGS_VM;

	vmcs_writel(GUEST_RFLAGS, flags);
	vmcs_writel(GUEST_CR4, vmcs_readl(GUEST_CR4) | X86_CR4_VME);
	vmx_update_exception_bitmap(vcpu);

	fix_rmode_seg(VCPU_SREG_SS, &vmx->rmode.segs[VCPU_SREG_SS]);
	fix_rmode_seg(VCPU_SREG_CS, &vmx->rmode.segs[VCPU_SREG_CS]);
	fix_rmode_seg(VCPU_SREG_ES, &vmx->rmode.segs[VCPU_SREG_ES]);
	fix_rmode_seg(VCPU_SREG_DS, &vmx->rmode.segs[VCPU_SREG_DS]);
	fix_rmode_seg(VCPU_SREG_GS, &vmx->rmode.segs[VCPU_SREG_GS]);
	fix_rmode_seg(VCPU_SREG_FS, &vmx->rmode.segs[VCPU_SREG_FS]);
}

int vmx_set_efer(struct kvm_vcpu *vcpu, u64 efer)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);

	/* Nothing to do if hardware doesn't support EFER. */
	if (!vmx_find_uret_msr(vmx, MSR_EFER))
		return 0;

	vcpu->arch.efer = efer;
#ifdef CONFIG_X86_64
	if (efer & EFER_LMA)
		vm_entry_controls_setbit(vmx, VM_ENTRY_IA32E_MODE);
	else
		vm_entry_controls_clearbit(vmx, VM_ENTRY_IA32E_MODE);
#else
	if (KVM_BUG_ON(efer & EFER_LMA, vcpu->kvm))
		return 1;
#endif

	vmx_setup_uret_msrs(vmx);
	return 0;
}

#ifdef CONFIG_X86_64

static void enter_lmode(struct kvm_vcpu *vcpu)
{
	u32 guest_tr_ar;

	vmx_segment_cache_clear(to_vmx(vcpu));

	guest_tr_ar = vmcs_read32(GUEST_TR_AR_BYTES);
	if ((guest_tr_ar & VMX_AR_TYPE_MASK) != VMX_AR_TYPE_BUSY_64_TSS) {
		pr_debug_ratelimited("%s: tss fixup for long mode. \n",
				     __func__);
		vmcs_write32(GUEST_TR_AR_BYTES,
			     (guest_tr_ar & ~VMX_AR_TYPE_MASK)
			     | VMX_AR_TYPE_BUSY_64_TSS);
	}
	vmx_set_efer(vcpu, vcpu->arch.efer | EFER_LMA);
}

static void exit_lmode(struct kvm_vcpu *vcpu)
{
	vmx_set_efer(vcpu, vcpu->arch.efer & ~EFER_LMA);
}

#endif

static void vmx_flush_tlb_all(struct kvm_vcpu *vcpu)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);

	/*
	 * INVEPT must be issued when EPT is enabled, irrespective of VPID, as
	 * the CPU is not required to invalidate guest-physical mappings on
	 * VM-Entry, even if VPID is disabled.  Guest-physical mappings are
	 * associated with the root EPT structure and not any particular VPID
	 * (INVVPID also isn't required to invalidate guest-physical mappings).
	 */
	if (enable_ept) {
		ept_sync_global();
	} else if (enable_vpid) {
		if (cpu_has_vmx_invvpid_global()) {
			vpid_sync_vcpu_global();
		} else {
			vpid_sync_vcpu_single(vmx->vpid);
			vpid_sync_vcpu_single(vmx->nested.vpid02);
		}
	}
}

static inline int vmx_get_current_vpid(struct kvm_vcpu *vcpu)
{
	if (is_guest_mode(vcpu))
		return nested_get_vpid02(vcpu);
	return to_vmx(vcpu)->vpid;
}

static void vmx_flush_tlb_current(struct kvm_vcpu *vcpu)
{
	struct kvm_mmu *mmu = vcpu->arch.mmu;
	u64 root_hpa = mmu->root.hpa;

	/* No flush required if the current context is invalid. */
	if (!VALID_PAGE(root_hpa))
		return;

	if (enable_ept)
		ept_sync_context(construct_eptp(vcpu, root_hpa,
						mmu->root_role.level));
	else
		vpid_sync_context(vmx_get_current_vpid(vcpu));
}

static void vmx_flush_tlb_gva(struct kvm_vcpu *vcpu, gva_t addr)
{
	/*
	 * vpid_sync_vcpu_addr() is a nop if vpid==0, see the comment in
	 * vmx_flush_tlb_guest() for an explanation of why this is ok.
	 */
	vpid_sync_vcpu_addr(vmx_get_current_vpid(vcpu), addr);
}

static void vmx_flush_tlb_guest(struct kvm_vcpu *vcpu)
{
	/*
	 * vpid_sync_context() is a nop if vpid==0, e.g. if enable_vpid==0 or a
	 * vpid couldn't be allocated for this vCPU.  VM-Enter and VM-Exit are
	 * required to flush GVA->{G,H}PA mappings from the TLB if vpid is
	 * disabled (VM-Enter with vpid enabled and vpid==0 is disallowed),
	 * i.e. no explicit INVVPID is necessary.
	 */
	vpid_sync_context(vmx_get_current_vpid(vcpu));
}

void vmx_ept_load_pdptrs(struct kvm_vcpu *vcpu)
{
	struct kvm_mmu *mmu = vcpu->arch.walk_mmu;

	if (!kvm_register_is_dirty(vcpu, VCPU_EXREG_PDPTR))
		return;

	if (is_pae_paging(vcpu)) {
		vmcs_write64(GUEST_PDPTR0, mmu->pdptrs[0]);
		vmcs_write64(GUEST_PDPTR1, mmu->pdptrs[1]);
		vmcs_write64(GUEST_PDPTR2, mmu->pdptrs[2]);
		vmcs_write64(GUEST_PDPTR3, mmu->pdptrs[3]);
	}
}

void ept_save_pdptrs(struct kvm_vcpu *vcpu)
{
	struct kvm_mmu *mmu = vcpu->arch.walk_mmu;

	if (WARN_ON_ONCE(!is_pae_paging(vcpu)))
		return;

	mmu->pdptrs[0] = vmcs_read64(GUEST_PDPTR0);
	mmu->pdptrs[1] = vmcs_read64(GUEST_PDPTR1);
	mmu->pdptrs[2] = vmcs_read64(GUEST_PDPTR2);
	mmu->pdptrs[3] = vmcs_read64(GUEST_PDPTR3);

	kvm_register_mark_available(vcpu, VCPU_EXREG_PDPTR);
}

#define CR3_EXITING_BITS (CPU_BASED_CR3_LOAD_EXITING | \
			  CPU_BASED_CR3_STORE_EXITING)

static bool vmx_is_valid_cr0(struct kvm_vcpu *vcpu, unsigned long cr0)
{
	if (is_guest_mode(vcpu))
		return nested_guest_cr0_valid(vcpu, cr0);

	if (to_vmx(vcpu)->nested.vmxon)
		return nested_host_cr0_valid(vcpu, cr0);

	return true;
}

void vmx_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	unsigned long hw_cr0, old_cr0_pg;
	u32 tmp;

	old_cr0_pg = kvm_read_cr0_bits(vcpu, X86_CR0_PG);

	hw_cr0 = (cr0 & ~KVM_VM_CR0_ALWAYS_OFF);
	if (enable_unrestricted_guest)
		hw_cr0 |= KVM_VM_CR0_ALWAYS_ON_UNRESTRICTED_GUEST;
	else {
		hw_cr0 |= KVM_VM_CR0_ALWAYS_ON;
		if (!enable_ept)
			hw_cr0 |= X86_CR0_WP;

		if (vmx->rmode.vm86_active && (cr0 & X86_CR0_PE))
			enter_pmode(vcpu);

		if (!vmx->rmode.vm86_active && !(cr0 & X86_CR0_PE))
			enter_rmode(vcpu);
	}

	vmcs_writel(CR0_READ_SHADOW, cr0);
	vmcs_writel(GUEST_CR0, hw_cr0);
	vcpu->arch.cr0 = cr0;
	kvm_register_mark_available(vcpu, VCPU_EXREG_CR0);

#ifdef CONFIG_X86_64
	if (vcpu->arch.efer & EFER_LME) {
		if (!old_cr0_pg && (cr0 & X86_CR0_PG))
			enter_lmode(vcpu);
		else if (old_cr0_pg && !(cr0 & X86_CR0_PG))
			exit_lmode(vcpu);
	}
#endif

	if (enable_ept && !enable_unrestricted_guest) {
		/*
		 * Ensure KVM has an up-to-date snapshot of the guest's CR3.  If
		 * the below code _enables_ CR3 exiting, vmx_cache_reg() will
		 * (correctly) stop reading vmcs.GUEST_CR3 because it thinks
		 * KVM's CR3 is installed.
		 */
		if (!kvm_register_is_available(vcpu, VCPU_EXREG_CR3))
			vmx_cache_reg(vcpu, VCPU_EXREG_CR3);

		/*
		 * When running with EPT but not unrestricted guest, KVM must
		 * intercept CR3 accesses when paging is _disabled_.  This is
		 * necessary because restricted guests can't actually run with
		 * paging disabled, and so KVM stuffs its own CR3 in order to
		 * run the guest when identity mapped page tables.
		 *
		 * Do _NOT_ check the old CR0.PG, e.g. to optimize away the
		 * update, it may be stale with respect to CR3 interception,
		 * e.g. after nested VM-Enter.
		 *
		 * Lastly, honor L1's desires, i.e. intercept CR3 loads and/or
		 * stores to forward them to L1, even if KVM does not need to
		 * intercept them to preserve its identity mapped page tables.
		 */
		if (!(cr0 & X86_CR0_PG)) {
			exec_controls_setbit(vmx, CR3_EXITING_BITS);
		} else if (!is_guest_mode(vcpu)) {
			exec_controls_clearbit(vmx, CR3_EXITING_BITS);
		} else {
			tmp = exec_controls_get(vmx);
			tmp &= ~CR3_EXITING_BITS;
			tmp |= get_vmcs12(vcpu)->cpu_based_vm_exec_control & CR3_EXITING_BITS;
			exec_controls_set(vmx, tmp);
		}

		/* Note, vmx_set_cr4() consumes the new vcpu->arch.cr0. */
		if ((old_cr0_pg ^ cr0) & X86_CR0_PG)
			vmx_set_cr4(vcpu, kvm_read_cr4(vcpu));

		/*
		 * When !CR0_PG -> CR0_PG, vcpu->arch.cr3 becomes active, but
		 * GUEST_CR3 is still vmx->ept_identity_map_addr if EPT + !URG.
		 */
		if (!(old_cr0_pg & X86_CR0_PG) && (cr0 & X86_CR0_PG))
			kvm_register_mark_dirty(vcpu, VCPU_EXREG_CR3);
	}

	/* depends on vcpu->arch.cr0 to be set to a new value */
	vmx->emulation_required = vmx_emulation_required(vcpu);
}

static int vmx_get_max_ept_level(void)
{
	if (cpu_has_vmx_ept_5levels())
		return 5;
	return 4;
}

u64 construct_eptp(struct kvm_vcpu *vcpu, hpa_t root_hpa, int root_level)
{
	u64 eptp = VMX_EPTP_MT_WB;

	eptp |= (root_level == 5) ? VMX_EPTP_PWL_5 : VMX_EPTP_PWL_4;

	if (enable_ept_ad_bits &&
	    (!is_guest_mode(vcpu) || nested_ept_ad_enabled(vcpu)))
		eptp |= VMX_EPTP_AD_ENABLE_BIT;
	eptp |= root_hpa;

	return eptp;
}

static void vmx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa,
			     int root_level)
{
	struct kvm *kvm = vcpu->kvm;
	bool update_guest_cr3 = true;
	unsigned long guest_cr3;
	u64 eptp;

	if (enable_ept) {
		eptp = construct_eptp(vcpu, root_hpa, root_level);
		vmcs_write64(EPT_POINTER, eptp);

		hv_track_root_tdp(vcpu, root_hpa);

		if (!enable_unrestricted_guest && !is_paging(vcpu))
			guest_cr3 = to_kvm_vmx(kvm)->ept_identity_map_addr;
		else if (kvm_register_is_dirty(vcpu, VCPU_EXREG_CR3))
			guest_cr3 = vcpu->arch.cr3;
		else /* vmcs.GUEST_CR3 is already up-to-date. */
			update_guest_cr3 = false;
		vmx_ept_load_pdptrs(vcpu);
	} else {
		guest_cr3 = root_hpa | kvm_get_active_pcid(vcpu);
	}

	if (update_guest_cr3)
		vmcs_writel(GUEST_CR3, guest_cr3);
}


static bool vmx_is_valid_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
{
	/*
	 * We operate under the default treatment of SMM, so VMX cannot be
	 * enabled under SMM.  Note, whether or not VMXE is allowed at all,
	 * i.e. is a reserved bit, is handled by common x86 code.
	 */
	if ((cr4 & X86_CR4_VMXE) && is_smm(vcpu))
		return false;

	if (to_vmx(vcpu)->nested.vmxon && !nested_cr4_valid(vcpu, cr4))
		return false;

	return true;
}

void vmx_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
{
	unsigned long old_cr4 = kvm_read_cr4(vcpu);
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	unsigned long hw_cr4;

	/*
	 * Pass through host's Machine Check Enable value to hw_cr4, which
	 * is in force while we are in guest mode.  Do not let guests control
	 * this bit, even if host CR4.MCE == 0.
	 */
	hw_cr4 = (cr4_read_shadow() & X86_CR4_MCE) | (cr4 & ~X86_CR4_MCE);
	if (enable_unrestricted_guest)
		hw_cr4 |= KVM_VM_CR4_ALWAYS_ON_UNRESTRICTED_GUEST;
	else if (vmx->rmode.vm86_active)
		hw_cr4 |= KVM_RMODE_VM_CR4_ALWAYS_ON;
	else
		hw_cr4 |= KVM_PMODE_VM_CR4_ALWAYS_ON;

	if (vmx_umip_emulated()) {
		if (cr4 & X86_CR4_UMIP) {
			secondary_exec_controls_setbit(vmx, SECONDARY_EXEC_DESC);
			hw_cr4 &= ~X86_CR4_UMIP;
		} else if (!is_guest_mode(vcpu) ||
			!nested_cpu_has2(get_vmcs12(vcpu), SECONDARY_EXEC_DESC)) {
			secondary_exec_controls_clearbit(vmx, SECONDARY_EXEC_DESC);
		}
	}

	vcpu->arch.cr4 = cr4;
	kvm_register_mark_available(vcpu, VCPU_EXREG_CR4);

	if (!enable_unrestricted_guest) {
		if (enable_ept) {
			if (!is_paging(vcpu)) {
				hw_cr4 &= ~X86_CR4_PAE;
				hw_cr4 |= X86_CR4_PSE;
			} else if (!(cr4 & X86_CR4_PAE)) {
				hw_cr4 &= ~X86_CR4_PAE;
			}
		}

		/*
		 * SMEP/SMAP/PKU is disabled if CPU is in non-paging mode in
		 * hardware.  To emulate this behavior, SMEP/SMAP/PKU needs
		 * to be manually disabled when guest switches to non-paging
		 * mode.
		 *
		 * If !enable_unrestricted_guest, the CPU is always running
		 * with CR0.PG=1 and CR4 needs to be modified.
		 * If enable_unrestricted_guest, the CPU automatically
		 * disables SMEP/SMAP/PKU when the guest sets CR0.PG=0.
		 */
		if (!is_paging(vcpu))
			hw_cr4 &= ~(X86_CR4_SMEP | X86_CR4_SMAP | X86_CR4_PKE);
	}

	vmcs_writel(CR4_READ_SHADOW, cr4);
	vmcs_writel(GUEST_CR4, hw_cr4);

	if ((cr4 ^ old_cr4) & (X86_CR4_OSXSAVE | X86_CR4_PKE))
		kvm_update_cpuid_runtime(vcpu);
}

void vmx_get_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	u32 ar;

	if (vmx->rmode.vm86_active && seg != VCPU_SREG_LDTR) {
		*var = vmx->rmode.segs[seg];
		if (seg == VCPU_SREG_TR
		    || var->selector == vmx_read_guest_seg_selector(vmx, seg))
			return;
		var->base = vmx_read_guest_seg_base(vmx, seg);
		var->selector = vmx_read_guest_seg_selector(vmx, seg);
		return;
	}
	var->base = vmx_read_guest_seg_base(vmx, seg);
	var->limit = vmx_read_guest_seg_limit(vmx, seg);
	var->selector = vmx_read_guest_seg_selector(vmx, seg);
	ar = vmx_read_guest_seg_ar(vmx, seg);
	var->unusable = (ar >> 16) & 1;
	var->type = ar & 15;
	var->s = (ar >> 4) & 1;
	var->dpl = (ar >> 5) & 3;
	/*
	 * Some userspaces do not preserve unusable property. Since usable
	 * segment has to be present according to VMX spec we can use present
	 * property to amend userspace bug by making unusable segment always
	 * nonpresent. vmx_segment_access_rights() already marks nonpresent
	 * segment as unusable.
	 */
	var->present = !var->unusable;
	var->avl = (ar >> 12) & 1;
	var->l = (ar >> 13) & 1;
	var->db = (ar >> 14) & 1;
	var->g = (ar >> 15) & 1;
}

static u64 vmx_get_segment_base(struct kvm_vcpu *vcpu, int seg)
{
	struct kvm_segment s;

	if (to_vmx(vcpu)->rmode.vm86_active) {
		vmx_get_segment(vcpu, &s, seg);
		return s.base;
	}
	return vmx_read_guest_seg_base(to_vmx(vcpu), seg);
}

int vmx_get_cpl(struct kvm_vcpu *vcpu)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);

	if (unlikely(vmx->rmode.vm86_active))
		return 0;
	else {
		int ar = vmx_read_guest_seg_ar(vmx, VCPU_SREG_SS);
		return VMX_AR_DPL(ar);
	}
}

static u32 vmx_segment_access_rights(struct kvm_segment *var)
{
	u32 ar;

	ar = var->type & 15;
	ar |= (var->s & 1) << 4;
	ar |= (var->dpl & 3) << 5;
	ar |= (var->present & 1) << 7;
	ar |= (var->avl & 1) << 12;
	ar |= (var->l & 1) << 13;
	ar |= (var->db & 1) << 14;
	ar |= (var->g & 1) << 15;
	ar |= (var->unusable || !var->present) << 16;

	return ar;
}

void __vmx_set_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	const struct kvm_vmx_segment_field *sf = &kvm_vmx_segment_fields[seg];

	vmx_segment_cache_clear(vmx);

	if (vmx->rmode.vm86_active && seg != VCPU_SREG_LDTR) {
		vmx->rmode.segs[seg] = *var;
		if (seg == VCPU_SREG_TR)
			vmcs_write16(sf->selector, var->selector);
		else if (var->s)
			fix_rmode_seg(seg, &vmx->rmode.segs[seg]);
		return;
	}

	vmcs_writel(sf->base, var->base);
	vmcs_write32(sf->limit, var->limit);
	vmcs_write16(sf->selector, var->selector);

	/*
	 *   Fix the "Accessed" bit in AR field of segment registers for older
	 * qemu binaries.
	 *   IA32 arch specifies that at the time of processor reset the
	 * "Accessed" bit in the AR field of segment registers is 1. And qemu
	 * is setting it to 0 in the userland code. This causes invalid guest
	 * state vmexit when "unrestricted guest" mode is turned on.
	 *    Fix for this setup issue in cpu_reset is being pushed in the qemu
	 * tree. Newer qemu binaries with that qemu fix would not need this
	 * kvm hack.
	 */
	if (is_unrestricted_guest(vcpu) && (seg != VCPU_SREG_LDTR))
		var->type |= 0x1; /* Accessed */

	vmcs_write32(sf->ar_bytes, vmx_segment_access_rights(var));
}

static void vmx_set_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg)
{
	__vmx_set_segment(vcpu, var, seg);

	to_vmx(vcpu)->emulation_required = vmx_emulation_required(vcpu);
}

static void vmx_get_cs_db_l_bits(struct kvm_vcpu *vcpu, int *db, int *l)
{
	u32 ar = vmx_read_guest_seg_ar(to_vmx(vcpu), VCPU_SREG_CS);

	*db = (ar >> 14) & 1;
	*l = (ar >> 13) & 1;
}

static void vmx_get_idt(struct kvm_vcpu *vcpu, struct desc_ptr *dt)
{
	dt->size = vmcs_read32(GUEST_IDTR_LIMIT);
	dt->address = vmcs_readl(GUEST_IDTR_BASE);
}

static void vmx_set_idt(struct kvm_vcpu *vcpu, struct desc_ptr *dt)
{
	vmcs_write32(GUEST_IDTR_LIMIT, dt->size);
	vmcs_writel(GUEST_IDTR_BASE, dt->address);
}

static void vmx_get_gdt(struct kvm_vcpu *vcpu, struct desc_ptr *dt)
{
	dt->size = vmcs_read32(GUEST_GDTR_LIMIT);
	dt->address = vmcs_readl(GUEST_GDTR_BASE);
}

static void vmx_set_gdt(struct kvm_vcpu *vcpu, struct desc_ptr *dt)
{
	vmcs_write32(GUEST_GDTR_LIMIT, dt->size);
	vmcs_writel(GUEST_GDTR_BASE, dt->address);
}

static bool rmode_segment_valid(struct kvm_vcpu *vcpu, int seg)
{
	struct kvm_segment var;
	u32 ar;

	vmx_get_segment(vcpu, &var, seg);
	var.dpl = 0x3;
	if (seg == VCPU_SREG_CS)
		var.type = 0x3;
	ar = vmx_segment_access_rights(&var);

	if (var.base != (var.selector << 4))
		return false;
	if (var.limit != 0xffff)
		return false;
	if (ar != 0xf3)
		return false;

	return true;
}

static bool code_segment_valid(struct kvm_vcpu *vcpu)
{
	struct kvm_segment cs;
	unsigned int cs_rpl;

	vmx_get_segment(vcpu, &cs, VCPU_SREG_CS);
	cs_rpl = cs.selector & SEGMENT_RPL_MASK;

	if (cs.unusable)
		return false;
	if (~cs.type & (VMX_AR_TYPE_CODE_MASK|VMX_AR_TYPE_ACCESSES_MASK))
		return false;
	if (!cs.s)
		return false;
	if (cs.type & VMX_AR_TYPE_WRITEABLE_MASK) {
		if (cs.dpl > cs_rpl)
			return false;
	} else {
		if (cs.dpl != cs_rpl)
			return false;
	}
	if (!cs.present)
		return false;

	/* TODO: Add Reserved field check, this'll require a new member in the kvm_segment_field structure */
	return true;
}

static bool stack_segment_valid(struct kvm_vcpu *vcpu)
{
	struct kvm_segment ss;
	unsigned int ss_rpl;

	vmx_get_segment(vcpu, &ss, VCPU_SREG_SS);
	ss_rpl = ss.selector & SEGMENT_RPL_MASK;

	if (ss.unusable)
		return true;
	if (ss.type != 3 && ss.type != 7)
		return false;
	if (!ss.s)
		return false;
	if (ss.dpl != ss_rpl) /* DPL != RPL */
		return false;
	if (!ss.present)
		return false;

	return true;
}

static bool data_segment_valid(struct kvm_vcpu *vcpu, int seg)
{
	struct kvm_segment var;
	unsigned int rpl;

	vmx_get_segment(vcpu, &var, seg);
	rpl = var.selector & SEGMENT_RPL_MASK;

	if (var.unusable)
		return true;
	if (!var.s)
		return false;
	if (!var.present)
		return false;
	if (~var.type & (VMX_AR_TYPE_CODE_MASK|VMX_AR_TYPE_WRITEABLE_MASK)) {
		if (var.dpl < rpl) /* DPL < RPL */
			return false;
	}

	/* TODO: Add other members to kvm_segment_field to allow checking for other access
	 * rights flags
	 */
	return true;
}

static bool tr_valid(struct kvm_vcpu *vcpu)
{
	struct kvm_segment tr;

	vmx_get_segment(vcpu, &tr, VCPU_SREG_TR);

	if (tr.unusable)
		return false;
	if (tr.selector & SEGMENT_TI_MASK)	/* TI = 1 */
		return false;
	if (tr.type != 3 && tr.type != 11) /* TODO: Check if guest is in IA32e mode */
		return false;
	if (!tr.present)
		return false;

	return true;
}

static bool ldtr_valid(struct kvm_vcpu *vcpu)
{
	struct kvm_segment ldtr;

	vmx_get_segment(vcpu, &ldtr, VCPU_SREG_LDTR);

	if (ldtr.unusable)
		return true;
	if (ldtr.selector & SEGMENT_TI_MASK)	/* TI = 1 */
		return false;
	if (ldtr.type != 2)
		return false;
	if (!ldtr.present)
		return false;

	return true;
}

static bool cs_ss_rpl_check(struct kvm_vcpu *vcpu)
{
	struct kvm_segment cs, ss;

	vmx_get_segment(vcpu, &cs, VCPU_SREG_CS);
	vmx_get_segment(vcpu, &ss, VCPU_SREG_SS);

	return ((cs.selector & SEGMENT_RPL_MASK) ==
		 (ss.selector & SEGMENT_RPL_MASK));
}

/*
 * Check if guest state is valid. Returns true if valid, false if
 * not.
 * We assume that registers are always usable
 */
bool __vmx_guest_state_valid(struct kvm_vcpu *vcpu)
{
	/* real mode guest state checks */
	if (!is_protmode(vcpu) || (vmx_get_rflags(vcpu) & X86_EFLAGS_VM)) {
		if (!rmode_segment_valid(vcpu, VCPU_SREG_CS))
			return false;
		if (!rmode_segment_valid(vcpu, VCPU_SREG_SS))
			return false;
		if (!rmode_segment_valid(vcpu, VCPU_SREG_DS))
			return false;
		if (!rmode_segment_valid(vcpu, VCPU_SREG_ES))
			return false;
		if (!rmode_segment_valid(vcpu, VCPU_SREG_FS))
			return false;
		if (!rmode_segment_valid(vcpu, VCPU_SREG_GS))
			return false;
	} else {
	/* protected mode guest state checks */
		if (!cs_ss_rpl_check(vcpu))
			return false;
		if (!code_segment_valid(vcpu))
			return false;
		if (!stack_segment_valid(vcpu))
			return false;
		if (!data_segment_valid(vcpu, VCPU_SREG_DS))
			return false;
		if (!data_segment_valid(vcpu, VCPU_SREG_ES))
			return false;
		if (!data_segment_valid(vcpu, VCPU_SREG_FS))
			return false;
		if (!data_segment_valid(vcpu, VCPU_SREG_GS))
			return false;
		if (!tr_valid(vcpu))
			return false;
		if (!ldtr_valid(vcpu))
			return false;
	}
	/* TODO:
	 * - Add checks on RIP
	 * - Add checks on RFLAGS
	 */

	return true;
}

static int init_rmode_tss(struct kvm *kvm, void __user *ua)
{
	const void *zero_page = (const void *) __va(page_to_phys(ZERO_PAGE(0)));
	u16 data;
	int i;

	for (i = 0; i < 3; i++) {
		if (__copy_to_user(ua + PAGE_SIZE * i, zero_page, PAGE_SIZE))
			return -EFAULT;
	}

	data = TSS_BASE_SIZE + TSS_REDIRECTION_SIZE;
	if (__copy_to_user(ua + TSS_IOPB_BASE_OFFSET, &data, sizeof(u16)))
		return -EFAULT;

	data = ~0;
	if (__copy_to_user(ua + RMODE_TSS_SIZE - 1, &data, sizeof(u8)))
		return -EFAULT;

	return 0;
}

static int init_rmode_identity_map(struct kvm *kvm)
{
	struct kvm_vmx *kvm_vmx = to_kvm_vmx(kvm);
	int i, r = 0;
	void __user *uaddr;
	u32 tmp;

	/* Protect kvm_vmx->ept_identity_pagetable_done. */
	mutex_lock(&kvm->slots_lock);

	if (likely(kvm_vmx->ept_identity_pagetable_done))
		goto out;

	if (!kvm_vmx->ept_identity_map_addr)
		kvm_vmx->ept_identity_map_addr = VMX_EPT_IDENTITY_PAGETABLE_ADDR;

	uaddr = __x86_set_memory_region(kvm,
					IDENTITY_PAGETABLE_PRIVATE_MEMSLOT,
					kvm_vmx->ept_identity_map_addr,
					PAGE_SIZE);
	if (IS_ERR(uaddr)) {
		r = PTR_ERR(uaddr);
		goto out;
	}

	/* Set up identity-mapping pagetable for EPT in real mode */
	for (i = 0; i < (PAGE_SIZE / sizeof(tmp)); i++) {
		tmp = (i << 22) + (_PAGE_PRESENT | _PAGE_RW | _PAGE_USER |
			_PAGE_ACCESSED | _PAGE_DIRTY | _PAGE_PSE);
		if (__copy_to_user(uaddr + i * sizeof(tmp), &tmp, sizeof(tmp))) {
			r = -EFAULT;
			goto out;
		}
	}
	kvm_vmx->ept_identity_pagetable_done = true;

out:
	mutex_unlock(&kvm->slots_lock);
	return r;
}

static void seg_setup(int seg)
{
	const struct kvm_vmx_segment_field *sf = &kvm_vmx_segment_fields[seg];
	unsigned int ar;

	vmcs_write16(sf->selector, 0);
	vmcs_writel(sf->base, 0);
	vmcs_write32(sf->limit, 0xffff);
	ar = 0x93;
	if (seg == VCPU_SREG_CS)
		ar |= 0x08; /* code segment */

	vmcs_write32(sf->ar_bytes, ar);
}

int allocate_vpid(void)
{
	int vpid;

	if (!enable_vpid)
		return 0;
	spin_lock(&vmx_vpid_lock);
	vpid = find_first_zero_bit(vmx_vpid_bitmap, VMX_NR_VPIDS);
	if (vpid < VMX_NR_VPIDS)
		__set_bit(vpid, vmx_vpid_bitmap);
	else
		vpid = 0;
	spin_unlock(&vmx_vpid_lock);
	return vpid;
}

void free_vpid(int vpid)
{
	if (!enable_vpid || vpid == 0)
		return;
	spin_lock(&vmx_vpid_lock);
	__clear_bit(vpid, vmx_vpid_bitmap);
	spin_unlock(&vmx_vpid_lock);
}

static void vmx_msr_bitmap_l01_changed(struct vcpu_vmx *vmx)
{
	/*
	 * When KVM is a nested hypervisor on top of Hyper-V and uses
	 * 'Enlightened MSR Bitmap' feature L0 needs to know that MSR
	 * bitmap has changed.
	 */
	if (kvm_is_using_evmcs()) {
		struct hv_enlightened_vmcs *evmcs = (void *)vmx->vmcs01.vmcs;

		if (evmcs->hv_enlightenments_control.msr_bitmap)
			evmcs->hv_clean_fields &=
				~HV_VMX_ENLIGHTENED_CLEAN_FIELD_MSR_BITMAP;
	}

	vmx->nested.force_msr_bitmap_recalc = true;
}

void vmx_disable_intercept_for_msr(struct kvm_vcpu *vcpu, u32 msr, int type)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	unsigned long *msr_bitmap = vmx->vmcs01.msr_bitmap;

	if (!cpu_has_vmx_msr_bitmap())
		return;

	vmx_msr_bitmap_l01_changed(vmx);

	/*
	 * Mark the desired intercept state in shadow bitmap, this is needed
	 * for resync when the MSR filters change.
	*/
	if (is_valid_passthrough_msr(msr)) {
		int idx = possible_passthrough_msr_slot(msr);

		if (idx != -ENOENT) {
			if (type & MSR_TYPE_R)
				clear_bit(idx, vmx->shadow_msr_intercept.read);
			if (type & MSR_TYPE_W)
				clear_bit(idx, vmx->shadow_msr_intercept.write);
		}
	}

	if ((type & MSR_TYPE_R) &&
	    !kvm_msr_allowed(vcpu, msr, KVM_MSR_FILTER_READ)) {
		vmx_set_msr_bitmap_read(msr_bitmap, msr);
		type &= ~MSR_TYPE_R;
	}

	if ((type & MSR_TYPE_W) &&
	    !kvm_msr_allowed(vcpu, msr, KVM_MSR_FILTER_WRITE)) {
		vmx_set_msr_bitmap_write(msr_bitmap, msr);
		type &= ~MSR_TYPE_W;
	}

	if (type & MSR_TYPE_R)
		vmx_clear_msr_bitmap_read(msr_bitmap, msr);

	if (type & MSR_TYPE_W)
		vmx_clear_msr_bitmap_write(msr_bitmap, msr);
}

void vmx_enable_intercept_for_msr(struct kvm_vcpu *vcpu, u32 msr, int type)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	unsigned long *msr_bitmap = vmx->vmcs01.msr_bitmap;

	if (!cpu_has_vmx_msr_bitmap())
		return;

	vmx_msr_bitmap_l01_changed(vmx);

	/*
	 * Mark the desired intercept state in shadow bitmap, this is needed
	 * for resync when the MSR filter changes.
	*/
	if (is_valid_passthrough_msr(msr)) {
		int idx = possible_passthrough_msr_slot(msr);

		if (idx != -ENOENT) {
			if (type & MSR_TYPE_R)
				set_bit(idx, vmx->shadow_msr_intercept.read);
			if (type & MSR_TYPE_W)
				set_bit(idx, vmx->shadow_msr_intercept.write);
		}
	}

	if (type & MSR_TYPE_R)
		vmx_set_msr_bitmap_read(msr_bitmap, msr);

	if (type & MSR_TYPE_W)
		vmx_set_msr_bitmap_write(msr_bitmap, msr);
}

static void vmx_update_msr_bitmap_x2apic(struct kvm_vcpu *vcpu)
{
	/*
	 * x2APIC indices for 64-bit accesses into the RDMSR and WRMSR halves
	 * of the MSR bitmap.  KVM emulates APIC registers up through 0x3f0,
	 * i.e. MSR 0x83f, and so only needs to dynamically manipulate 64 bits.
	 */
	const int read_idx = APIC_BASE_MSR / BITS_PER_LONG_LONG;
	const int write_idx = read_idx + (0x800 / sizeof(u64));
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	u64 *msr_bitmap = (u64 *)vmx->vmcs01.msr_bitmap;
	u8 mode;

	if (!cpu_has_vmx_msr_bitmap() || WARN_ON_ONCE(!lapic_in_kernel(vcpu)))
		return;

	if (cpu_has_secondary_exec_ctrls() &&
	    (secondary_exec_controls_get(vmx) &
	     SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE)) {
		mode = MSR_BITMAP_MODE_X2APIC;
		if (enable_apicv && kvm_vcpu_apicv_active(vcpu))
			mode |= MSR_BITMAP_MODE_X2APIC_APICV;
	} else {
		mode = 0;
	}

	if (mode == vmx->x2apic_msr_bitmap_mode)
		return;

	vmx->x2apic_msr_bitmap_mode = mode;

	/*
	 * Reset the bitmap for MSRs 0x800 - 0x83f.  Leave AMD's uber-extended
	 * registers (0x840 and above) intercepted, KVM doesn't support them.
	 * Intercept all writes by default and poke holes as needed.  Pass
	 * through reads for all valid registers by default in x2APIC+APICv
	 * mode, only the current timer count needs on-demand emulation by KVM.
	 */
	if (mode & MSR_BITMAP_MODE_X2APIC_APICV)
		msr_bitmap[read_idx] = ~kvm_lapic_readable_reg_mask(vcpu->arch.apic);
	else
		msr_bitmap[read_idx] = ~0ull;
	msr_bitmap[write_idx] = ~0ull;

	/*
	 * TPR reads and writes can be virtualized even if virtual interrupt
	 * delivery is not in use.
	 */
	vmx_set_intercept_for_msr(vcpu, X2APIC_MSR(APIC_TASKPRI), MSR_TYPE_RW,
				  !(mode & MSR_BITMAP_MODE_X2APIC));

	if (mode & MSR_BITMAP_MODE_X2APIC_APICV) {
		vmx_enable_intercept_for_msr(vcpu, X2APIC_MSR(APIC_TMCCT), MSR_TYPE_RW);
		vmx_disable_intercept_for_msr(vcpu, X2APIC_MSR(APIC_EOI), MSR_TYPE_W);
		vmx_disable_intercept_for_msr(vcpu, X2APIC_MSR(APIC_SELF_IPI), MSR_TYPE_W);
		if (enable_ipiv)
			vmx_disable_intercept_for_msr(vcpu, X2APIC_MSR(APIC_ICR), MSR_TYPE_RW);
	}
}

void pt_update_intercept_for_msr(struct kvm_vcpu *vcpu)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	bool flag = !(vmx->pt_desc.guest.ctl & RTIT_CTL_TRACEEN);
	u32 i;

	vmx_set_intercept_for_msr(vcpu, MSR_IA32_RTIT_STATUS, MSR_TYPE_RW, flag);
	vmx_set_intercept_for_msr(vcpu, MSR_IA32_RTIT_OUTPUT_BASE, MSR_TYPE_RW, flag);
	vmx_set_intercept_for_msr(vcpu, MSR_IA32_RTIT_OUTPUT_MASK, MSR_TYPE_RW, flag);
	vmx_set_intercept_for_msr(vcpu, MSR_IA32_RTIT_CR3_MATCH, MSR_TYPE_RW, flag);
	for (i = 0; i < vmx->pt_desc.num_address_ranges; i++) {
		vmx_set_intercept_for_msr(vcpu, MSR_IA32_RTIT_ADDR0_A + i * 2, MSR_TYPE_RW, flag);
		vmx_set_intercept_for_msr(vcpu, MSR_IA32_RTIT_ADDR0_B + i * 2, MSR_TYPE_RW, flag);
	}
}

static bool vmx_guest_apic_has_interrupt(struct kvm_vcpu *vcpu)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	void *vapic_page;
	u32 vppr;
	int rvi;

	if (WARN_ON_ONCE(!is_guest_mode(vcpu)) ||
		!nested_cpu_has_vid(get_vmcs12(vcpu)) ||
		WARN_ON_ONCE(!vmx->nested.virtual_apic_map.gfn))
		return false;

	rvi = vmx_get_rvi();

	vapic_page = vmx->nested.virtual_apic_map.hva;
	vppr = *((u32 *)(vapic_page + APIC_PROCPRI));

	return ((rvi & 0xf0) > (vppr & 0xf0));
}

static void vmx_msr_filter_changed(struct kvm_vcpu *vcpu)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	u32 i;

	/*
	 * Redo intercept permissions for MSRs that KVM is passing through to
	 * the guest.  Disabling interception will check the new MSR filter and
	 * ensure that KVM enables interception if usersepace wants to filter
	 * the MSR.  MSRs that KVM is already intercepting don't need to be
	 * refreshed since KVM is going to intercept them regardless of what
	 * userspace wants.
	 */
	for (i = 0; i < ARRAY_SIZE(vmx_possible_passthrough_msrs); i++) {
		u32 msr = vmx_possible_passthrough_msrs[i];

		if (!test_bit(i, vmx->shadow_msr_intercept.read))
			vmx_disable_intercept_for_msr(vcpu, msr, MSR_TYPE_R);

		if (!test_bit(i, vmx->shadow_msr_intercept.write))
			vmx_disable_intercept_for_msr(vcpu, msr, MSR_TYPE_W);
	}

	/* PT MSRs can be passed through iff PT is exposed to the guest. */
	if (vmx_pt_mode_is_host_guest())
		pt_update_intercept_for_msr(vcpu);
}

static inline void kvm_vcpu_trigger_posted_interrupt(struct kvm_vcpu *vcpu,
						     int pi_vec)
{
#ifdef CONFIG_SMP
	if (vcpu->mode == IN_GUEST_MODE) {
		/*
		 * The vector of the virtual has already been set in the PIR.
		 * Send a notification event to deliver the virtual interrupt
		 * unless the vCPU is the currently running vCPU, i.e. the
		 * event is being sent from a fastpath VM-Exit handler, in
		 * which case the PIR will be synced to the vIRR before
		 * re-entering the guest.
		 *
		 * When the target is not the running vCPU, the following
		 * possibilities emerge:
		 *
		 * Case 1: vCPU stays in non-root mode. Sending a notification
		 * event posts the interrupt to the vCPU.
		 *
		 * Case 2: vCPU exits to root mode and is still runnable. The
		 * PIR will be synced to the vIRR before re-entering the guest.
		 * Sending a notification event is ok as the host IRQ handler
		 * will ignore the spurious event.
		 *
		 * Case 3: vCPU exits to root mode and is blocked. vcpu_block()
		 * has already synced PIR to vIRR and never blocks the vCPU if
		 * the vIRR is not empty. Therefore, a blocked vCPU here does
		 * not wait for any requested interrupts in PIR, and sending a
		 * notification event also results in a benign, spurious event.
		 */

		if (vcpu != kvm_get_running_vcpu())
			__apic_send_IPI_mask(get_cpu_mask(vcpu->cpu), pi_vec);
		return;
	}
#endif
	/*
	 * The vCPU isn't in the guest; wake the vCPU in case it is blocking,
	 * otherwise do nothing as KVM will grab the highest priority pending
	 * IRQ via ->sync_pir_to_irr() in vcpu_enter_guest().
	 */
	kvm_vcpu_wake_up(vcpu);
}

static int vmx_deliver_nested_posted_interrupt(struct kvm_vcpu *vcpu,
						int vector)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);

	if (is_guest_mode(vcpu) &&
	    vector == vmx->nested.posted_intr_nv) {
		/*
		 * If a posted intr is not recognized by hardware,
		 * we will accomplish it in the next vmentry.
		 */
		vmx->nested.pi_pending = true;
		kvm_make_request(KVM_REQ_EVENT, vcpu);

		/*
		 * This pairs with the smp_mb_*() after setting vcpu->mode in
		 * vcpu_enter_guest() to guarantee the vCPU sees the event
		 * request if triggering a posted interrupt "fails" because
		 * vcpu->mode != IN_GUEST_MODE.  The extra barrier is needed as
		 * the smb_wmb() in kvm_make_request() only ensures everything
		 * done before making the request is visible when the request
		 * is visible, it doesn't ensure ordering between the store to
		 * vcpu->requests and the load from vcpu->mode.
		 */
		smp_mb__after_atomic();

		/* the PIR and ON have been set by L1. */
		kvm_vcpu_trigger_posted_interrupt(vcpu, POSTED_INTR_NESTED_VECTOR);
		return 0;
	}
	return -1;
}
/*
 * Send interrupt to vcpu via posted interrupt way.
 * 1. If target vcpu is running(non-root mode), send posted interrupt
 * notification to vcpu and hardware will sync PIR to vIRR atomically.
 * 2. If target vcpu isn't running(root mode), kick it to pick up the
 * interrupt from PIR in next vmentry.
 */
static int vmx_deliver_posted_interrupt(struct kvm_vcpu *vcpu, int vector)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	int r;

	r = vmx_deliver_nested_posted_interrupt(vcpu, vector);
	if (!r)
		return 0;

	/* Note, this is called iff the local APIC is in-kernel. */
	if (!vcpu->arch.apic->apicv_active)
		return -1;

	if (pi_test_and_set_pir(vector, &vmx->pi_desc))
		return 0;

	/* If a previous notification has sent the IPI, nothing to do.  */
	if (pi_test_and_set_on(&vmx->pi_desc))
		return 0;

	/*
	 * The implied barrier in pi_test_and_set_on() pairs with the smp_mb_*()
	 * after setting vcpu->mode in vcpu_enter_guest(), thus the vCPU is
	 * guaranteed to see PID.ON=1 and sync the PIR to IRR if triggering a
	 * posted interrupt "fails" because vcpu->mode != IN_GUEST_MODE.
	 */
	kvm_vcpu_trigger_posted_interrupt(vcpu, POSTED_INTR_VECTOR);
	return 0;
}

static void vmx_deliver_interrupt(struct kvm_lapic *apic, int delivery_mode,
				  int trig_mode, int vector)
{
	struct kvm_vcpu *vcpu = apic->vcpu;

	if (vmx_deliver_posted_interrupt(vcpu, vector)) {
		kvm_lapic_set_irr(vector, apic);
		kvm_make_request(KVM_REQ_EVENT, vcpu);
		kvm_vcpu_kick(vcpu);
	} else {
		trace_kvm_apicv_accept_irq(vcpu->vcpu_id, delivery_mode,
					   trig_mode, vector);
	}
}

/*
 * Set up the vmcs's constant host-state fields, i.e., host-state fields that
 * will not change in the lifetime of the guest.
 * Note that host-state that does change is set elsewhere. E.g., host-state
 * that is set differently for each CPU is set in vmx_vcpu_load(), not here.
 */
void vmx_set_constant_host_state(struct vcpu_vmx *vmx)
{
	u32 low32, high32;
	unsigned long tmpl;
	unsigned long cr0, cr3, cr4;

	cr0 = read_cr0();
	WARN_ON(cr0 & X86_CR0_TS);
	vmcs_writel(HOST_CR0, cr0);  /* 22.2.3 */

	/*
	 * Save the most likely value for this task's CR3 in the VMCS.
	 * We can't use __get_current_cr3_fast() because we're not atomic.
	 */
	cr3 = __read_cr3();
	vmcs_writel(HOST_CR3, cr3);		/* 22.2.3  FIXME: shadow tables */
	vmx->loaded_vmcs->host_state.cr3 = cr3;

	/* Save the most likely value for this task's CR4 in the VMCS. */
	cr4 = cr4_read_shadow();
	vmcs_writel(HOST_CR4, cr4);			/* 22.2.3, 22.2.5 */
	vmx->loaded_vmcs->host_state.cr4 = cr4;

	vmcs_write16(HOST_CS_SELECTOR, __KERNEL_CS);  /* 22.2.4 */
#ifdef CONFIG_X86_64
	/*
	 * Load null selectors, so we can avoid reloading them in
	 * vmx_prepare_switch_to_host(), in case userspace uses
	 * the null selectors too (the expected case).
	 */
	vmcs_write16(HOST_DS_SELECTOR, 0);
	vmcs_write16(HOST_ES_SELECTOR, 0);
#else
	vmcs_write16(HOST_DS_SELECTOR, __KERNEL_DS);  /* 22.2.4 */
	vmcs_write16(HOST_ES_SELECTOR, __KERNEL_DS);  /* 22.2.4 */
#endif
	vmcs_write16(HOST_SS_SELECTOR, __KERNEL_DS);  /* 22.2.4 */
	vmcs_write16(HOST_TR_SELECTOR, GDT_ENTRY_TSS*8);  /* 22.2.4 */

	vmcs_writel(HOST_IDTR_BASE, host_idt_base);   /* 22.2.4 */

	vmcs_writel(HOST_RIP, (unsigned long)vmx_vmexit); /* 22.2.5 */

	rdmsr(MSR_IA32_SYSENTER_CS, low32, high32);
	vmcs_write32(HOST_IA32_SYSENTER_CS, low32);

	/*
	 * SYSENTER is used for 32-bit system calls on either 32-bit or
	 * 64-bit kernels.  It is always zero If neither is allowed, otherwise
	 * vmx_vcpu_load_vmcs loads it with the per-CPU entry stack (and may
	 * have already done so!).
	 */
	if (!IS_ENABLED(CONFIG_IA32_EMULATION) && !IS_ENABLED(CONFIG_X86_32))
		vmcs_writel(HOST_IA32_SYSENTER_ESP, 0);

	rdmsrl(MSR_IA32_SYSENTER_EIP, tmpl);
	vmcs_writel(HOST_IA32_SYSENTER_EIP, tmpl);   /* 22.2.3 */

	if (vmcs_config.vmexit_ctrl & VM_EXIT_LOAD_IA32_PAT) {
		rdmsr(MSR_IA32_CR_PAT, low32, high32);
		vmcs_write64(HOST_IA32_PAT, low32 | ((u64) high32 << 32));
	}

	if (cpu_has_load_ia32_efer())
		vmcs_write64(HOST_IA32_EFER, host_efer);
}

void set_cr4_guest_host_mask(struct vcpu_vmx *vmx)
{
	struct kvm_vcpu *vcpu = &vmx->vcpu;

	vcpu->arch.cr4_guest_owned_bits = KVM_POSSIBLE_CR4_GUEST_BITS &
					  ~vcpu->arch.cr4_guest_rsvd_bits;
	if (!enable_ept) {
		vcpu->arch.cr4_guest_owned_bits &= ~X86_CR4_TLBFLUSH_BITS;
		vcpu->arch.cr4_guest_owned_bits &= ~X86_CR4_PDPTR_BITS;
	}
	if (is_guest_mode(&vmx->vcpu))
		vcpu->arch.cr4_guest_owned_bits &=
			~get_vmcs12(vcpu)->cr4_guest_host_mask;
	vmcs_writel(CR4_GUEST_HOST_MASK, ~vcpu->arch.cr4_guest_owned_bits);
}

static u32 vmx_pin_based_exec_ctrl(struct vcpu_vmx *vmx)
{
	u32 pin_based_exec_ctrl = vmcs_config.pin_based_exec_ctrl;

	if (!kvm_vcpu_apicv_active(&vmx->vcpu))
		pin_based_exec_ctrl &= ~PIN_BASED_POSTED_INTR;

	if (!enable_vnmi)
		pin_based_exec_ctrl &= ~PIN_BASED_VIRTUAL_NMIS;

	if (!enable_preemption_timer)
		pin_based_exec_ctrl &= ~PIN_BASED_VMX_PREEMPTION_TIMER;

	return pin_based_exec_ctrl;
}

static u32 vmx_vmentry_ctrl(void)
{
	u32 vmentry_ctrl = vmcs_config.vmentry_ctrl;

	if (vmx_pt_mode_is_system())
		vmentry_ctrl &= ~(VM_ENTRY_PT_CONCEAL_PIP |
				  VM_ENTRY_LOAD_IA32_RTIT_CTL);
	/*
	 * IA32e mode, and loading of EFER and PERF_GLOBAL_CTRL are toggled dynamically.
	 */
	vmentry_ctrl &= ~(VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL |
			  VM_ENTRY_LOAD_IA32_EFER |
			  VM_ENTRY_IA32E_MODE);

	if (cpu_has_perf_global_ctrl_bug())
		vmentry_ctrl &= ~VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL;

	return vmentry_ctrl;
}

static u32 vmx_vmexit_ctrl(void)
{
	u32 vmexit_ctrl = vmcs_config.vmexit_ctrl;

	/*
	 * Not used by KVM and never set in vmcs01 or vmcs02, but emulated for
	 * nested virtualization and thus allowed to be set in vmcs12.
	 */
	vmexit_ctrl &= ~(VM_EXIT_SAVE_IA32_PAT | VM_EXIT_SAVE_IA32_EFER |
			 VM_EXIT_SAVE_VMX_PREEMPTION_TIMER);

	if (vmx_pt_mode_is_system())
		vmexit_ctrl &= ~(VM_EXIT_PT_CONCEAL_PIP |
				 VM_EXIT_CLEAR_IA32_RTIT_CTL);

	if (cpu_has_perf_global_ctrl_bug())
		vmexit_ctrl &= ~VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL;

	/* Loading of EFER and PERF_GLOBAL_CTRL are toggled dynamically */
	return vmexit_ctrl &
		~(VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL | VM_EXIT_LOAD_IA32_EFER);
}

static void vmx_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);

	if (is_guest_mode(vcpu)) {
		vmx->nested.update_vmcs01_apicv_status = true;
		return;
	}

	pin_controls_set(vmx, vmx_pin_based_exec_ctrl(vmx));

	if (kvm_vcpu_apicv_active(vcpu)) {
		secondary_exec_controls_setbit(vmx,
					       SECONDARY_EXEC_APIC_REGISTER_VIRT |
					       SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY);
		if (enable_ipiv)
			tertiary_exec_controls_setbit(vmx, TERTIARY_EXEC_IPI_VIRT);
	} else {
		secondary_exec_controls_clearbit(vmx,
						 SECONDARY_EXEC_APIC_REGISTER_VIRT |
						 SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY);
		if (enable_ipiv)
			tertiary_exec_controls_clearbit(vmx, TERTIARY_EXEC_IPI_VIRT);
	}

	vmx_update_msr_bitmap_x2apic(vcpu);
}

static u32 vmx_exec_control(struct vcpu_vmx *vmx)
{
	u32 exec_control = vmcs_config.cpu_based_exec_ctrl;

	/*
	 * Not used by KVM, but fully supported for nesting, i.e. are allowed in
	 * vmcs12 and propagated to vmcs02 when set in vmcs12.
	 */
	exec_control &= ~(CPU_BASED_RDTSC_EXITING |
			  CPU_BASED_USE_IO_BITMAPS |
			  CPU_BASED_MONITOR_TRAP_FLAG |
			  CPU_BASED_PAUSE_EXITING);

	/* INTR_WINDOW_EXITING and NMI_WINDOW_EXITING are toggled dynamically */
	exec_control &= ~(CPU_BASED_INTR_WINDOW_EXITING |
			  CPU_BASED_NMI_WINDOW_EXITING);

	if (vmx->vcpu.arch.switch_db_regs & KVM_DEBUGREG_WONT_EXIT)
		exec_control &= ~CPU_BASED_MOV_DR_EXITING;

	if (!cpu_need_tpr_shadow(&vmx->vcpu))
		exec_control &= ~CPU_BASED_TPR_SHADOW;

#ifdef CONFIG_X86_64
	if (exec_control & CPU_BASED_TPR_SHADOW)
		exec_control &= ~(CPU_BASED_CR8_LOAD_EXITING |
				  CPU_BASED_CR8_STORE_EXITING);
	else
		exec_control |= CPU_BASED_CR8_STORE_EXITING |
				CPU_BASED_CR8_LOAD_EXITING;
#endif
	/* No need to intercept CR3 access or INVPLG when using EPT. */
	if (enable_ept)
		exec_control &= ~(CPU_BASED_CR3_LOAD_EXITING |
				  CPU_BASED_CR3_STORE_EXITING |
				  CPU_BASED_INVLPG_EXITING);
	if (kvm_mwait_in_guest(vmx->vcpu.kvm))
		exec_control &= ~(CPU_BASED_MWAIT_EXITING |
				CPU_BASED_MONITOR_EXITING);
	if (kvm_hlt_in_guest(vmx->vcpu.kvm))
		exec_control &= ~CPU_BASED_HLT_EXITING;
	return exec_control;
}

static u64 vmx_tertiary_exec_control(struct vcpu_vmx *vmx)
{
	u64 exec_control = vmcs_config.cpu_based_3rd_exec_ctrl;

	/*
	 * IPI virtualization relies on APICv. Disable IPI virtualization if
	 * APICv is inhibited.
	 */
	if (!enable_ipiv || !kvm_vcpu_apicv_active(&vmx->vcpu))
		exec_control &= ~TERTIARY_EXEC_IPI_VIRT;

	return exec_control;
}

/*
 * Adjust a single secondary execution control bit to intercept/allow an
 * instruction in the guest.  This is usually done based on whether or not a
 * feature has been exposed to the guest in order to correctly emulate faults.
 */
static inline void
vmx_adjust_secondary_exec_control(struct vcpu_vmx *vmx, u32 *exec_control,
				  u32 control, bool enabled, bool exiting)
{
	/*
	 * If the control is for an opt-in feature, clear the control if the
	 * feature is not exposed to the guest, i.e. not enabled.  If the
	 * control is opt-out, i.e. an exiting control, clear the control if
	 * the feature _is_ exposed to the guest, i.e. exiting/interception is
	 * disabled for the associated instruction.  Note, the caller is
	 * responsible presetting exec_control to set all supported bits.
	 */
	if (enabled == exiting)
		*exec_control &= ~control;

	/*
	 * Update the nested MSR settings so that a nested VMM can/can't set
	 * controls for features that are/aren't exposed to the guest.
	 */
	if (nested) {
		/*
		 * All features that can be added or removed to VMX MSRs must
		 * be supported in the first place for nested virtualization.
		 */
		if (WARN_ON_ONCE(!(vmcs_config.nested.secondary_ctls_high & control)))
			enabled = false;

		if (enabled)
			vmx->nested.msrs.secondary_ctls_high |= control;
		else
			vmx->nested.msrs.secondary_ctls_high &= ~control;
	}
}

/*
 * Wrapper macro for the common case of adjusting a secondary execution control
 * based on a single guest CPUID bit, with a dedicated feature bit.  This also
 * verifies that the control is actually supported by KVM and hardware.
 */
#define vmx_adjust_sec_exec_control(vmx, exec_control, name, feat_name, ctrl_name, exiting)	\
({												\
	struct kvm_vcpu *__vcpu = &(vmx)->vcpu;							\
	bool __enabled;										\
												\
	if (cpu_has_vmx_##name()) {								\
		if (kvm_is_governed_feature(X86_FEATURE_##feat_name))				\
			__enabled = guest_can_use(__vcpu, X86_FEATURE_##feat_name);		\
		else										\
			__enabled = guest_cpuid_has(__vcpu, X86_FEATURE_##feat_name);		\
		vmx_adjust_secondary_exec_control(vmx, exec_control, SECONDARY_EXEC_##ctrl_name,\
						  __enabled, exiting);				\
	}											\
})

/* More macro magic for ENABLE_/opt-in versus _EXITING/opt-out controls. */
#define vmx_adjust_sec_exec_feature(vmx, exec_control, lname, uname) \
	vmx_adjust_sec_exec_control(vmx, exec_control, lname, uname, ENABLE_##uname, false)

#define vmx_adjust_sec_exec_exiting(vmx, exec_control, lname, uname) \
	vmx_adjust_sec_exec_control(vmx, exec_control, lname, uname, uname##_EXITING, true)

static u32 vmx_secondary_exec_control(struct vcpu_vmx *vmx)
{
	struct kvm_vcpu *vcpu = &vmx->vcpu;

	u32 exec_control = vmcs_config.cpu_based_2nd_exec_ctrl;

	if (vmx_pt_mode_is_system())
		exec_control &= ~(SECONDARY_EXEC_PT_USE_GPA | SECONDARY_EXEC_PT_CONCEAL_VMX);
	if (!cpu_need_virtualize_apic_accesses(vcpu))
		exec_control &= ~SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES;
	if (vmx->vpid == 0)
		exec_control &= ~SECONDARY_EXEC_ENABLE_VPID;
	if (!enable_ept) {
		exec_control &= ~SECONDARY_EXEC_ENABLE_EPT;
		enable_unrestricted_guest = 0;
	}
	if (!enable_unrestricted_guest)
		exec_control &= ~SECONDARY_EXEC_UNRESTRICTED_GUEST;
	if (kvm_pause_in_guest(vmx->vcpu.kvm))
		exec_control &= ~SECONDARY_EXEC_PAUSE_LOOP_EXITING;
	if (!kvm_vcpu_apicv_active(vcpu))
		exec_control &= ~(SECONDARY_EXEC_APIC_REGISTER_VIRT |
				  SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY);
	exec_control &= ~SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE;

	/*
	 * KVM doesn't support VMFUNC for L1, but the control is set in KVM's
	 * base configuration as KVM emulates VMFUNC[EPTP_SWITCHING] for L2.
	 */
	exec_control &= ~SECONDARY_EXEC_ENABLE_VMFUNC;

	/* SECONDARY_EXEC_DESC is enabled/disabled on writes to CR4.UMIP,
	 * in vmx_set_cr4.  */
	exec_control &= ~SECONDARY_EXEC_DESC;

	/* SECONDARY_EXEC_SHADOW_VMCS is enabled when L1 executes VMPTRLD
	   (handle_vmptrld).
	   We can NOT enable shadow_vmcs here because we don't have yet
	   a current VMCS12
	*/
	exec_control &= ~SECONDARY_EXEC_SHADOW_VMCS;

	/*
	 * PML is enabled/disabled when dirty logging of memsmlots changes, but
	 * it needs to be set here when dirty logging is already active, e.g.
	 * if this vCPU was created after dirty logging was enabled.
	 */
	if (!enable_pml || !atomic_read(&vcpu->kvm->nr_memslots_dirty_logging))
		exec_control &= ~SECONDARY_EXEC_ENABLE_PML;

	vmx_adjust_sec_exec_feature(vmx, &exec_control, xsaves, XSAVES);

	/*
	 * RDPID is also gated by ENABLE_RDTSCP, turn on the control if either
	 * feature is exposed to the guest.  This creates a virtualization hole
	 * if both are supported in hardware but only one is exposed to the
	 * guest, but letting the guest execute RDTSCP or RDPID when either one
	 * is advertised is preferable to emulating the advertised instruction
	 * in KVM on #UD, and obviously better than incorrectly injecting #UD.
	 */
	if (cpu_has_vmx_rdtscp()) {
		bool rdpid_or_rdtscp_enabled =
			guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP) ||
			guest_cpuid_has(vcpu, X86_FEATURE_RDPID);

		vmx_adjust_secondary_exec_control(vmx, &exec_control,
						  SECONDARY_EXEC_ENABLE_RDTSCP,
						  rdpid_or_rdtscp_enabled, false);
	}

	vmx_adjust_sec_exec_feature(vmx, &exec_control, invpcid, INVPCID);

	vmx_adjust_sec_exec_exiting(vmx, &exec_control, rdrand, RDRAND);
	vmx_adjust_sec_exec_exiting(vmx, &exec_control, rdseed, RDSEED);

	vmx_adjust_sec_exec_control(vmx, &exec_control, waitpkg, WAITPKG,
				    ENABLE_USR_WAIT_PAUSE, false);

	if (!vcpu->kvm->arch.bus_lock_detection_enabled)
		exec_control &= ~SECONDARY_EXEC_BUS_LOCK_DETECTION;

	if (!kvm_notify_vmexit_enabled(vcpu->kvm))
		exec_control &= ~SECONDARY_EXEC_NOTIFY_VM_EXITING;

	return exec_control;
}

static inline int vmx_get_pid_table_order(struct kvm *kvm)
{
	return get_order(kvm->arch.max_vcpu_ids * sizeof(*to_kvm_vmx(kvm)->pid_table));
}

static int vmx_alloc_ipiv_pid_table(struct kvm *kvm)
{
	struct page *pages;
	struct kvm_vmx *kvm_vmx = to_kvm_vmx(kvm);

	if (!irqchip_in_kernel(kvm) || !enable_ipiv)
		return 0;

	if (kvm_vmx->pid_table)
		return 0;

	pages = alloc_pages(GFP_KERNEL_ACCOUNT | __GFP_ZERO,
			    vmx_get_pid_table_order(kvm));
	if (!pages)
		return -ENOMEM;

	kvm_vmx->pid_table = (void *)page_address(pages);
	return 0;
}

static int vmx_vcpu_precreate(struct kvm *kvm)
{
	return vmx_alloc_ipiv_pid_table(kvm);
}

#define VMX_XSS_EXIT_BITMAP 0

static void init_vmcs(struct vcpu_vmx *vmx)
{
	struct kvm *kvm = vmx->vcpu.kvm;
	struct kvm_vmx *kvm_vmx = to_kvm_vmx(kvm);

	if (nested)
		nested_vmx_set_vmcs_shadowing_bitmap();

	if (cpu_has_vmx_msr_bitmap())
		vmcs_write64(MSR_BITMAP, __pa(vmx->vmcs01.msr_bitmap));

	vmcs_write64(VMCS_LINK_POINTER, INVALID_GPA); /* 22.3.1.5 */

	/* Control */
	pin_controls_set(vmx, vmx_pin_based_exec_ctrl(vmx));

	exec_controls_set(vmx, vmx_exec_control(vmx));

	if (cpu_has_secondary_exec_ctrls())
		secondary_exec_controls_set(vmx, vmx_secondary_exec_control(vmx));

	if (cpu_has_tertiary_exec_ctrls())
		tertiary_exec_controls_set(vmx, vmx_tertiary_exec_control(vmx));

	if (enable_apicv && lapic_in_kernel(&vmx->vcpu)) {
		vmcs_write64(EOI_EXIT_BITMAP0, 0);
		vmcs_write64(EOI_EXIT_BITMAP1, 0);
		vmcs_write64(EOI_EXIT_BITMAP2, 0);
		vmcs_write64(EOI_EXIT_BITMAP3, 0);

		vmcs_write16(GUEST_INTR_STATUS, 0);

		vmcs_write16(POSTED_INTR_NV, POSTED_INTR_VECTOR);
		vmcs_write64(POSTED_INTR_DESC_ADDR, __pa((&vmx->pi_desc)));
	}

	if (vmx_can_use_ipiv(&vmx->vcpu)) {
		vmcs_write64(PID_POINTER_TABLE, __pa(kvm_vmx->pid_table));
		vmcs_write16(LAST_PID_POINTER_INDEX, kvm->arch.max_vcpu_ids - 1);
	}

	if (!kvm_pause_in_guest(kvm)) {
		vmcs_write32(PLE_GAP, ple_gap);
		vmx->ple_window = ple_window;
		vmx->ple_window_dirty = true;
	}

	if (kvm_notify_vmexit_enabled(kvm))
		vmcs_write32(NOTIFY_WINDOW, kvm->arch.notify_window);

	vmcs_write32(PAGE_FAULT_ERROR_CODE_MASK, 0);
	vmcs_write32(PAGE_FAULT_ERROR_CODE_MATCH, 0);
	vmcs_write32(CR3_TARGET_COUNT, 0);           /* 22.2.1 */

	vmcs_write16(HOST_FS_SELECTOR, 0);            /* 22.2.4 */
	vmcs_write16(HOST_GS_SELECTOR, 0);            /* 22.2.4 */
	vmx_set_constant_host_state(vmx);
	vmcs_writel(HOST_FS_BASE, 0); /* 22.2.4 */
	vmcs_writel(HOST_GS_BASE, 0); /* 22.2.4 */

	if (cpu_has_vmx_vmfunc())
		vmcs_write64(VM_FUNCTION_CONTROL, 0);

	vmcs_write32(VM_EXIT_MSR_STORE_COUNT, 0);
	vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, 0);
	vmcs_write64(VM_EXIT_MSR_LOAD_ADDR, __pa(vmx->msr_autoload.host.val));
	vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, 0);
	vmcs_write64(VM_ENTRY_MSR_LOAD_ADDR, __pa(vmx->msr_autoload.guest.val));

	if (vmcs_config.vmentry_ctrl & VM_ENTRY_LOAD_IA32_PAT)
		vmcs_write64(GUEST_IA32_PAT, vmx->vcpu.arch.pat);

	vm_exit_controls_set(vmx, vmx_vmexit_ctrl());

	/* 22.2.1, 20.8.1 */
	vm_entry_controls_set(vmx, vmx_vmentry_ctrl());

	vmx->vcpu.arch.cr0_guest_owned_bits = vmx_l1_guest_owned_cr0_bits();
	vmcs_writel(CR0_GUEST_HOST_MASK, ~vmx->vcpu.arch.cr0_guest_owned_bits);

	set_cr4_guest_host_mask(vmx);

	if (vmx->vpid != 0)
		vmcs_write16(VIRTUAL_PROCESSOR_ID, vmx->vpid);

	if (cpu_has_vmx_xsaves())
		vmcs_write64(XSS_EXIT_BITMAP, VMX_XSS_EXIT_BITMAP);

	if (enable_pml) {
		vmcs_write64(PML_ADDRESS, page_to_phys(vmx->pml_pg));
		vmcs_write16(GUEST_PML_INDEX, PML_ENTITY_NUM - 1);
	}

	vmx_write_encls_bitmap(&vmx->vcpu, NULL);

	if (vmx_pt_mode_is_host_guest()) {
		memset(&vmx->pt_desc, 0, sizeof(vmx->pt_desc));
		/* Bit[6~0] are forced to 1, writes are ignored. */
		vmx->pt_desc.guest.output_mask = 0x7F;
		vmcs_write64(GUEST_IA32_RTIT_CTL, 0);
	}

	vmcs_write32(GUEST_SYSENTER_CS, 0);
	vmcs_writel(GUEST_SYSENTER_ESP, 0);
	vmcs_writel(GUEST_SYSENTER_EIP, 0);
	vmcs_write64(GUEST_IA32_DEBUGCTL, 0);

	if (cpu_has_vmx_tpr_shadow()) {
		vmcs_write64(VIRTUAL_APIC_PAGE_ADDR, 0);
		if (cpu_need_tpr_shadow(&vmx->vcpu))
			vmcs_write64(VIRTUAL_APIC_PAGE_ADDR,
				     __pa(vmx->vcpu.arch.apic->regs));
		vmcs_write32(TPR_THRESHOLD, 0);
	}

	vmx_setup_uret_msrs(vmx);
}

static void __vmx_vcpu_reset(struct kvm_vcpu *vcpu)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);

	init_vmcs(vmx);

	if (nested)
		memcpy(&vmx->nested.msrs, &vmcs_config.nested, sizeof(vmx->nested.msrs));

	vcpu_setup_sgx_lepubkeyhash(vcpu);

	vmx->nested.posted_intr_nv = -1;
	vmx->nested.vmxon_ptr = INVALID_GPA;
	vmx->nested.current_vmptr = INVALID_GPA;
	vmx->nested.hv_evmcs_vmptr = EVMPTR_INVALID;

	vcpu->arch.microcode_version = 0x100000000ULL;
	vmx->msr_ia32_feature_control_valid_bits = FEAT_CTL_LOCKED;

	/*
	 * Enforce invariant: pi_desc.nv is always either POSTED_INTR_VECTOR
	 * or POSTED_INTR_WAKEUP_VECTOR.
	 */
	vmx->pi_desc.nv = POSTED_INTR_VECTOR;
	vmx->pi_desc.sn = 1;
}

static void vmx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);

	if (!init_event)
		__vmx_vcpu_reset(vcpu);

	vmx->rmode.vm86_active = 0;
	vmx->spec_ctrl = 0;

	vmx->msr_ia32_umwait_control = 0;

	vmx->hv_deadline_tsc = -1;
	kvm_set_cr8(vcpu, 0);

	vmx_segment_cache_clear(vmx);
	kvm_register_mark_available(vcpu, VCPU_EXREG_SEGMENTS);

	seg_setup(VCPU_SREG_CS);
	vmcs_write16(GUEST_CS_SELECTOR, 0xf000);
	vmcs_writel(GUEST_CS_BASE, 0xffff0000ul);

	seg_setup(VCPU_SREG_DS);
	seg_setup(VCPU_SREG_ES);
	seg_setup(VCPU_SREG_FS);
	seg_setup(VCPU_SREG_GS);
	seg_setup(VCPU_SREG_SS);

	vmcs_write16(GUEST_TR_SELECTOR, 0);
	vmcs_writel(GUEST_TR_BASE, 0);
	vmcs_write32(GUEST_TR_LIMIT, 0xffff);
	vmcs_write32(GUEST_TR_AR_BYTES, 0x008b);

	vmcs_write16(GUEST_LDTR_SELECTOR, 0);
	vmcs_writel(GUEST_LDTR_BASE, 0);
	vmcs_write32(GUEST_LDTR_LIMIT, 0xffff);
	vmcs_write32(GUEST_LDTR_AR_BYTES, 0x00082);

	vmcs_writel(GUEST_GDTR_BASE, 0);
	vmcs_write32(GUEST_GDTR_LIMIT, 0xffff);

	vmcs_writel(GUEST_IDTR_BASE, 0);
	vmcs_write32(GUEST_IDTR_LIMIT, 0xffff);

	vmcs_write32(GUEST_ACTIVITY_STATE, GUEST_ACTIVITY_ACTIVE);
	vmcs_write32(GUEST_INTERRUPTIBILITY_INFO, 0);
	vmcs_writel(GUEST_PENDING_DBG_EXCEPTIONS, 0);
	if (kvm_mpx_supported())
		vmcs_write64(GUEST_BNDCFGS, 0);

	vmcs_write32(VM_ENTRY_INTR_INFO_FIELD, 0);  /* 22.2.1 */

	kvm_make_request(KVM_REQ_APIC_PAGE_RELOAD, vcpu);

	vpid_sync_context(vmx->vpid);

	vmx_update_fb_clear_dis(vcpu, vmx);
}

static void vmx_enable_irq_window(struct kvm_vcpu *vcpu)
{
	exec_controls_setbit(to_vmx(vcpu), CPU_BASED_INTR_WINDOW_EXITING);
}

static void vmx_enable_nmi_window(struct kvm_vcpu *vcpu)
{
	if (!enable_vnmi ||
	    vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) & GUEST_INTR_STATE_STI) {
		vmx_enable_irq_window(vcpu);
		return;
	}

	exec_controls_setbit(to_vmx(vcpu), CPU_BASED_NMI_WINDOW_EXITING);
}

static void vmx_inject_irq(struct kvm_vcpu *vcpu, bool reinjected)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	uint32_t intr;
	int irq = vcpu->arch.interrupt.nr;

	trace_kvm_inj_virq(irq, vcpu->arch.interrupt.soft, reinjected);

	++vcpu->stat.irq_injections;
	if (vmx->rmode.vm86_active) {
		int inc_eip = 0;
		if (vcpu->arch.interrupt.soft)
			inc_eip = vcpu->arch.event_exit_inst_len;
		kvm_inject_realmode_interrupt(vcpu, irq, inc_eip);
		return;
	}
	intr = irq | INTR_INFO_VALID_MASK;
	if (vcpu->arch.interrupt.soft) {
		intr |= INTR_TYPE_SOFT_INTR;
		vmcs_write32(VM_ENTRY_INSTRUCTION_LEN,
			     vmx->vcpu.arch.event_exit_inst_len);
	} else
		intr |= INTR_TYPE_EXT_INTR;
	vmcs_write32(VM_ENTRY_INTR_INFO_FIELD, intr);

	vmx_clear_hlt(vcpu);
}

static void vmx_inject_nmi(struct kvm_vcpu *vcpu)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);

	if (!enable_vnmi) {
		/*
		 * Tracking the NMI-blocked state in software is built upon
		 * finding the next open IRQ window. This, in turn, depends on
		 * well-behaving guests: They have to keep IRQs disabled at
		 * least as long as the NMI handler runs. Otherwise we may
		 * cause NMI nesting, maybe breaking the guest. But as this is
		 * highly unlikely, we can live with the residual risk.
		 */
		vmx->loaded_vmcs->soft_vnmi_blocked = 1;
		vmx->loaded_vmcs->vnmi_blocked_time = 0;
	}

	++vcpu->stat.nmi_injections;
	vmx->loaded_vmcs->nmi_known_unmasked = false;

	if (vmx->rmode.vm86_active) {
		kvm_inject_realmode_interrupt(vcpu, NMI_VECTOR, 0);
		return;
	}

	vmcs_write32(VM_ENTRY_INTR_INFO_FIELD,
			INTR_TYPE_NMI_INTR | INTR_INFO_VALID_MASK | NMI_VECTOR);

	vmx_clear_hlt(vcpu);
}

bool vmx_get_nmi_mask(struct kvm_vcpu *vcpu)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	bool masked;

	if (!enable_vnmi)
		return vmx->loaded_vmcs->soft_vnmi_blocked;
	if (vmx->loaded_vmcs->nmi_known_unmasked)
		return false;
	masked = vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) & GUEST_INTR_STATE_NMI;
	vmx->loaded_vmcs->nmi_known_unmasked = !masked;
	return masked;
}

void vmx_set_nmi_mask(struct kvm_vcpu *vcpu, bool masked)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);

	if (!enable_vnmi) {
		if (vmx->loaded_vmcs->soft_vnmi_blocked != masked) {
			vmx->loaded_vmcs->soft_vnmi_blocked = masked;
			vmx->loaded_vmcs->vnmi_blocked_time = 0;
		}
	} else {
		vmx->loaded_vmcs->nmi_known_unmasked = !masked;
		if (masked)
			vmcs_set_bits(GUEST_INTERRUPTIBILITY_INFO,
				      GUEST_INTR_STATE_NMI);
		else
			vmcs_clear_bits(GUEST_INTERRUPTIBILITY_INFO,
					GUEST_INTR_STATE_NMI);
	}
}

bool vmx_nmi_blocked(struct kvm_vcpu *vcpu)
{
	if (is_guest_mode(vcpu) && nested_exit_on_nmi(vcpu))
		return false;

	if (!enable_vnmi && to_vmx(vcpu)->loaded_vmcs->soft_vnmi_blocked)
		return true;

	return (vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) &
		(GUEST_INTR_STATE_MOV_SS | GUEST_INTR_STATE_STI |
		 GUEST_INTR_STATE_NMI));
}

static int vmx_nmi_allowed(struct kvm_vcpu *vcpu, bool for_injection)
{
	if (to_vmx(vcpu)->nested.nested_run_pending)
		return -EBUSY;

	/* An NMI must not be injected into L2 if it's supposed to VM-Exit.  */
	if (for_injection && is_guest_mode(vcpu) && nested_exit_on_nmi(vcpu))
		return -EBUSY;

	return !vmx_nmi_blocked(vcpu);
}

bool vmx_interrupt_blocked(struct kvm_vcpu *vcpu)
{
	if (is_guest_mode(vcpu) && nested_exit_on_intr(vcpu))
		return false;

	return !(vmx_get_rflags(vcpu) & X86_EFLAGS_IF) ||
	       (vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) &
		(GUEST_INTR_STATE_STI | GUEST_INTR_STATE_MOV_SS));
}

static int vmx_interrupt_allowed(struct kvm_vcpu *vcpu, bool for_injection)
{
	if (to_vmx(vcpu)->nested.nested_run_pending)
		return -EBUSY;

	/*
	 * An IRQ must not be injected into L2 if it's supposed to VM-Exit,
	 * e.g. if the IRQ arrived asynchronously after checking nested events.
	 */
	if (for_injection && is_guest_mode(vcpu) && nested_exit_on_intr(vcpu))
		return -EBUSY;

	return !vmx_interrupt_blocked(vcpu);
}

static int vmx_set_tss_addr(struct kvm *kvm, unsigned int addr)
{
	void __user *ret;

	if (enable_unrestricted_guest)
		return 0;

	mutex_lock(&kvm->slots_lock);
	ret = __x86_set_memory_region(kvm, TSS_PRIVATE_MEMSLOT, addr,
				      PAGE_SIZE * 3);
	mutex_unlock(&kvm->slots_lock);

	if (IS_ERR(ret))
		return PTR_ERR(ret);

	to_kvm_vmx(kvm)->tss_addr = addr;

	return init_rmode_tss(kvm, ret);
}

static int vmx_set_identity_map_addr(struct kvm *kvm, u64 ident_addr)
{
	to_kvm_vmx(kvm)->ept_identity_map_addr = ident_addr;
	return 0;
}

static bool rmode_exception(struct kvm_vcpu *vcpu, int vec)
{
	switch (vec) {
	case BP_VECTOR:
		/*
		 * Update instruction length as we may reinject the exception
		 * from user space while in guest debugging mode.
		 */
		to_vmx(vcpu)->vcpu.arch.event_exit_inst_len =
			vmcs_read32(VM_EXIT_INSTRUCTION_LEN);
		if (vcpu->guest_debug & KVM_GUESTDBG_USE_SW_BP)
			return false;
		fallthrough;
	case DB_VECTOR:
		return !(vcpu->guest_debug &
			(KVM_GUESTDBG_SINGLESTEP | KVM_GUESTDBG_USE_HW_BP));
	case DE_VECTOR:
	case OF_VECTOR:
	case BR_VECTOR:
	case UD_VECTOR:
	case DF_VECTOR:
	case SS_VECTOR:
	case GP_VECTOR:
	case MF_VECTOR:
		return true;
	}
	return false;
}

static int handle_rmode_exception(struct kvm_vcpu *vcpu,
				  int vec, u32 err_code)
{
	/*
	 * Instruction with address size override prefix opcode 0x67
	 * Cause the #SS fault with 0 error code in VM86 mode.
	 */
	if (((vec == GP_VECTOR) || (vec == SS_VECTOR)) && err_code == 0) {
		if (kvm_emulate_instruction(vcpu, 0)) {
			if (vcpu->arch.halt_request) {
				vcpu->arch.halt_request = 0;
				return kvm_emulate_halt_noskip(vcpu);
			}
			return 1;
		}
		return 0;
	}

	/*
	 * Forward all other exceptions that are valid in real mode.
	 * FIXME: Breaks guest debugging in real mode, needs to be fixed with
	 *        the required debugging infrastructure rework.
	 */
	kvm_queue_exception(vcpu, vec);
	return 1;
}

static int handle_machine_check(struct kvm_vcpu *vcpu)
{
	/* handled by vmx_vcpu_run() */
	return 1;
}

/*
 * If the host has split lock detection disabled, then #AC is
 * unconditionally injected into the guest, which is the pre split lock
 * detection behaviour.
 *
 * If the host has split lock detection enabled then #AC is
 * only injected into the guest when:
 *  - Guest CPL == 3 (user mode)
 *  - Guest has #AC detection enabled in CR0
 *  - Guest EFLAGS has AC bit set
 */
bool vmx_guest_inject_ac(struct kvm_vcpu *vcpu)
{
	if (!boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT))
		return true;

	return vmx_get_cpl(vcpu) == 3 && kvm_is_cr0_bit_set(vcpu, X86_CR0_AM) &&
	       (kvm_get_rflags(vcpu) & X86_EFLAGS_AC);
}

static int handle_exception_nmi(struct kvm_vcpu *vcpu)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	struct kvm_run *kvm_run = vcpu->run;
	u32 intr_info, ex_no, error_code;
	unsigned long cr2, dr6;
	u32 vect_info;

	vect_info = vmx->idt_vectoring_info;
	intr_info = vmx_get_intr_info(vcpu);

	/*
	 * Machine checks are handled by handle_exception_irqoff(), or by
	 * vmx_vcpu_run() if a #MC occurs on VM-Entry.  NMIs are handled by
	 * vmx_vcpu_enter_exit().
	 */
	if (is_machine_check(intr_info) || is_nmi(intr_info))
		return 1;

	/*
	 * Queue the exception here instead of in handle_nm_fault_irqoff().
	 * This ensures the nested_vmx check is not skipped so vmexit can
	 * be reflected to L1 (when it intercepts #NM) before reaching this
	 * point.
	 */
	if (is_nm_fault(intr_info)) {
		kvm_queue_exception(vcpu, NM_VECTOR);
		return 1;
	}

	if (is_invalid_opcode(intr_info))
		return handle_ud(vcpu);

	error_code = 0;
	if (intr_info & INTR_INFO_DELIVER_CODE_MASK)
		error_code = vmcs_read32(VM_EXIT_INTR_ERROR_CODE);

	if (!vmx->rmode.vm86_active && is_gp_fault(intr_info)) {
		WARN_ON_ONCE(!enable_vmware_backdoor);

		/*
		 * VMware backdoor emulation on #GP interception only handles
		 * IN{S}, OUT{S}, and RDPMC, none of which generate a non-zero
		 * error code on #GP.
		 */
		if (error_code) {
			kvm_queue_exception_e(vcpu, GP_VECTOR, error_code);
			return 1;
		}
		return kvm_emulate_instruction(vcpu, EMULTYPE_VMWARE_GP);
	}

	/*
	 * The #PF with PFEC.RSVD = 1 indicates the guest is accessing
	 * MMIO, it is better to report an internal error.
	 * See the comments in vmx_handle_exit.
	 */
	if ((vect_info & VECTORING_INFO_VALID_MASK) &&
	    !(is_page_fault(intr_info) && !(error_code & PFERR_RSVD_MASK))) {
		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
		vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_SIMUL_EX;
		vcpu->run->internal.ndata = 4;
		vcpu->run->internal.data[0] = vect_info;
		vcpu->run->internal.data[1] = intr_info;
		vcpu->run->internal.data[2] = error_code;
		vcpu->run->internal.data[3] = vcpu->arch.last_vmentry_cpu;
		return 0;
	}

	if (is_page_fault(intr_info)) {
		cr2 = vmx_get_exit_qual(vcpu);
		if (enable_ept && !vcpu->arch.apf.host_apf_flags) {
			/*
			 * EPT will cause page fault only if we need to
			 * detect illegal GPAs.
			 */
			WARN_ON_ONCE(!allow_smaller_maxphyaddr);
			kvm_fixup_and_inject_pf_error(vcpu, cr2, error_code);
			return 1;
		} else
			return kvm_handle_page_fault(vcpu, error_code, cr2, NULL, 0);
	}

	ex_no = intr_info & INTR_INFO_VECTOR_MASK;

	if (vmx->rmode.vm86_active && rmode_exception(vcpu, ex_no))
		return handle_rmode_exception(vcpu, ex_no, error_code);

	switch (ex_no) {
	case DB_VECTOR:
		dr6 = vmx_get_exit_qual(vcpu);
		if (!(vcpu->guest_debug &
		      (KVM_GUESTDBG_SINGLESTEP | KVM_GUESTDBG_USE_HW_BP))) {
			/*
			 * If the #DB was due to ICEBP, a.k.a. INT1, skip the
			 * instruction.  ICEBP generates a trap-like #DB, but
			 * despite its interception control being tied to #DB,
			 * is an instruction intercept, i.e. the VM-Exit occurs
			 * on the ICEBP itself.  Use the inner "skip" helper to
			 * avoid single-step #DB and MTF updates, as ICEBP is
			 * higher priority.  Note, skipping ICEBP still clears
			 * STI and MOVSS blocking.
			 *
			 * For all other #DBs, set vmcs.PENDING_DBG_EXCEPTIONS.BS
			 * if single-step is enabled in RFLAGS and STI or MOVSS
			 * blocking is active, as the CPU doesn't set the bit
			 * on VM-Exit due to #DB interception.  VM-Entry has a
			 * consistency check that a single-step #DB is pending
			 * in this scenario as the previous instruction cannot
			 * have toggled RFLAGS.TF 0=>1 (because STI and POP/MOV
			 * don't modify RFLAGS), therefore the one instruction
			 * delay when activating single-step breakpoints must
			 * have already expired.  Note, the CPU sets/clears BS
			 * as appropriate for all other VM-Exits types.
			 */
			if (is_icebp(intr_info))
				WARN_ON(!skip_emulated_instruction(vcpu));
			else if ((vmx_get_rflags(vcpu) & X86_EFLAGS_TF) &&
				 (vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) &
				  (GUEST_INTR_STATE_STI | GUEST_INTR_STATE_MOV_SS)))
				vmcs_writel(GUEST_PENDING_DBG_EXCEPTIONS,
					    vmcs_readl(GUEST_PENDING_DBG_EXCEPTIONS) | DR6_BS);

			kvm_queue_exception_p(vcpu, DB_VECTOR, dr6);
			return 1;
		}
		kvm_run->debug.arch.dr6 = dr6 | DR6_ACTIVE_LOW;
		kvm_run->debug.arch.dr7 = vmcs_readl(GUEST_DR7);
		fallthrough;
	case BP_VECTOR:
		/*
		 * Update instruction length as we may reinject #BP from
		 * user space while in guest debugging mode. Reading it for
		 * #DB as well causes no harm, it is not used in that case.
		 */
		vmx->vcpu.arch.event_exit_inst_len =
			vmcs_read32(VM_EXIT_INSTRUCTION_LEN);
		kvm_run->exit_reason = KVM_EXIT_DEBUG;
		kvm_run->debug.arch.pc = kvm_get_linear_rip(vcpu);
		kvm_run->debug.arch.exception = ex_no;
		break;
	case AC_VECTOR:
		if (vmx_guest_inject_ac(vcpu)) {
			kvm_queue_exception_e(vcpu, AC_VECTOR, error_code);
			return 1;
		}

		/*
		 * Handle split lock. Depending on detection mode this will
		 * either warn and disable split lock detection for this
		 * task or force SIGBUS on it.
		 */
		if (handle_guest_split_lock(kvm_rip_read(vcpu)))
			return 1;
		fallthrough;
	default:
		kvm_run->exit_reason = KVM_EXIT_EXCEPTION;
		kvm_run->ex.exception = ex_no;
		kvm_run->ex.error_code = error_code;
		break;
	}
	return 0;
}

static __always_inline int handle_external_interrupt(struct kvm_vcpu *vcpu)
{
	++vcpu->stat.irq_exits;
	return 1;
}

static int handle_triple_fault(struct kvm_vcpu *vcpu)
{
	vcpu->run->exit_reason = KVM_EXIT_SHUTDOWN;
	vcpu->mmio_needed = 0;
	return 0;
}

static int handle_io(struct kvm_vcpu *vcpu)
{
	unsigned long exit_qualification;
	int size, in, string;
	unsigned port;

	exit_qualification = vmx_get_exit_qual(vcpu);
	string = (exit_qualification & 16) != 0;

	++vcpu->stat.io_exits;

	if (string)
		return kvm_emulate_instruction(vcpu, 0);

	port = exit_qualification >> 16;
	size = (exit_qualification & 7) + 1;
	in = (exit_qualification & 8) != 0;

	return kvm_fast_pio(vcpu, size, port, in);
}

static void
vmx_patch_hypercall(struct kvm_vcpu *vcpu, unsigned char *hypercall)
{
	/*
	 * Patch in the VMCALL instruction:
	 */
	hypercall[0] = 0x0f;
	hypercall[1] = 0x01;
	hypercall[2] = 0xc1;
}

/* called to set cr0 as appropriate for a mov-to-cr0 exit. */
static int handle_set_cr0(struct kvm_vcpu *vcpu, unsigned long val)
{
	if (is_guest_mode(vcpu)) {
		struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
		unsigned long orig_val = val;

		/*
		 * We get here when L2 changed cr0 in a way that did not change
		 * any of L1's shadowed bits (see nested_vmx_exit_handled_cr),
		 * but did change L0 shadowed bits. So we first calculate the
		 * effective cr0 value that L1 would like to write into the
		 * hardware. It consists of the L2-owned bits from the new
		 * value combined with the L1-owned bits from L1's guest_cr0.
		 */
		val = (val & ~vmcs12->cr0_guest_host_mask) |
			(vmcs12->guest_cr0 & vmcs12->cr0_guest_host_mask);

		if (kvm_set_cr0(vcpu, val))
			return 1;
		vmcs_writel(CR0_READ_SHADOW, orig_val);
		return 0;
	} else {
		return kvm_set_cr0(vcpu, val);
	}
}

static int handle_set_cr4(struct kvm_vcpu *vcpu, unsigned long val)
{
	if (is_guest_mode(vcpu)) {
		struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
		unsigned long orig_val = val;

		/* analogously to handle_set_cr0 */
		val = (val & ~vmcs12->cr4_guest_host_mask) |
			(vmcs12->guest_cr4 & vmcs12->cr4_guest_host_mask);
		if (kvm_set_cr4(vcpu, val))
			return 1;
		vmcs_writel(CR4_READ_SHADOW, orig_val);
		return 0;
	} else
		return kvm_set_cr4(vcpu, val);
}

static int handle_desc(struct kvm_vcpu *vcpu)
{
	/*
	 * UMIP emulation relies on intercepting writes to CR4.UMIP, i.e. this
	 * and other code needs to be updated if UMIP can be guest owned.
	 */
	BUILD_BUG_ON(KVM_POSSIBLE_CR4_GUEST_BITS & X86_CR4_UMIP);

	WARN_ON_ONCE(!kvm_is_cr4_bit_set(vcpu, X86_CR4_UMIP));
	return kvm_emulate_instruction(vcpu, 0);
}

static int handle_cr(struct kvm_vcpu *vcpu)
{
	unsigned long exit_qualification, val;
	int cr;
	int reg;
	int err;
	int ret;

	exit_qualification = vmx_get_exit_qual(vcpu);
	cr = exit_qualification & 15;
	reg = (exit_qualification >> 8) & 15;
	switch ((exit_qualification >> 4) & 3) {
	case 0: /* mov to cr */
		val = kvm_register_read(vcpu, reg);
		trace_kvm_cr_write(cr, val);
		switch (cr) {
		case 0:
			err = handle_set_cr0(vcpu, val);
			return kvm_complete_insn_gp(vcpu, err);
		case 3:
			WARN_ON_ONCE(enable_unrestricted_guest);

			err = kvm_set_cr3(vcpu, val);
			return kvm_complete_insn_gp(vcpu, err);
		case 4:
			err = handle_set_cr4(vcpu, val);
			return kvm_complete_insn_gp(vcpu, err);
		case 8: {
				u8 cr8_prev = kvm_get_cr8(vcpu);
				u8 cr8 = (u8)val;
				err = kvm_set_cr8(vcpu, cr8);
				ret = kvm_complete_insn_gp(vcpu, err);
				if (lapic_in_kernel(vcpu))
					return ret;
				if (cr8_prev <= cr8)
					return ret;
				/*
				 * TODO: we might be squashing a
				 * KVM_GUESTDBG_SINGLESTEP-triggered
				 * KVM_EXIT_DEBUG here.
				 */
				vcpu->run->exit_reason = KVM_EXIT_SET_TPR;
				return 0;
			}
		}
		break;
	case 2: /* clts */
		KVM_BUG(1, vcpu->kvm, "Guest always owns CR0.TS");
		return -EIO;
	case 1: /*mov from cr*/
		switch (cr) {
		case 3:
			WARN_ON_ONCE(enable_unrestricted_guest);

			val = kvm_read_cr3(vcpu);
			kvm_register_write(vcpu, reg, val);
			trace_kvm_cr_read(cr, val);
			return kvm_skip_emulated_instruction(vcpu);
		case 8:
			val = kvm_get_cr8(vcpu);
			kvm_register_write(vcpu, reg, val);
			trace_kvm_cr_read(cr, val);
			return kvm_skip_emulated_instruction(vcpu);
		}
		break;
	case 3: /* lmsw */
		val = (exit_qualification >> LMSW_SOURCE_DATA_SHIFT) & 0x0f;
		trace_kvm_cr_write(0, (kvm_read_cr0_bits(vcpu, ~0xful) | val));
		kvm_lmsw(vcpu, val);

		return kvm_skip_emulated_instruction(vcpu);
	default:
		break;
	}
	vcpu->run->exit_reason = 0;
	vcpu_unimpl(vcpu, "unhandled control register: op %d cr %d\n",
	       (int)(exit_qualification >> 4) & 3, cr);
	return 0;
}

static int handle_dr(struct kvm_vcpu *vcpu)
{
	unsigned long exit_qualification;
	int dr, dr7, reg;
	int err = 1;

	exit_qualification = vmx_get_exit_qual(vcpu);
	dr = exit_qualification & DEBUG_REG_ACCESS_NUM;

	/* First, if DR does not exist, trigger UD */
	if (!kvm_require_dr(vcpu, dr))
		return 1;

	if (vmx_get_cpl(vcpu) > 0)
		goto out;

	dr7 = vmcs_readl(GUEST_DR7);
	if (dr7 & DR7_GD) {
		/*
		 * As the vm-exit takes precedence over the debug trap, we
		 * need to emulate the latter, either for the host or the
		 * guest debugging itself.
		 */
		if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP) {
			vcpu->run->debug.arch.dr6 = DR6_BD | DR6_ACTIVE_LOW;
			vcpu->run->debug.arch.dr7 = dr7;
			vcpu->run->debug.arch.pc = kvm_get_linear_rip(vcpu);
			vcpu->run->debug.arch.exception = DB_VECTOR;
			vcpu->run->exit_reason = KVM_EXIT_DEBUG;
			return 0;
		} else {
			kvm_queue_exception_p(vcpu, DB_VECTOR, DR6_BD);
			return 1;
		}
	}

	if (vcpu->guest_debug == 0) {
		exec_controls_clearbit(to_vmx(vcpu), CPU_BASED_MOV_DR_EXITING);

		/*
		 * No more DR vmexits; force a reload of the debug registers
		 * and reenter on this instruction.  The next vmexit will
		 * retrieve the full state of the debug registers.
		 */
		vcpu->arch.switch_db_regs |= KVM_DEBUGREG_WONT_EXIT;
		return 1;
	}

	reg = DEBUG_REG_ACCESS_REG(exit_qualification);
	if (exit_qualification & TYPE_MOV_FROM_DR) {
		unsigned long val;

		kvm_get_dr(vcpu, dr, &val);
		kvm_register_write(vcpu, reg, val);
		err = 0;
	} else {
		err = kvm_set_dr(vcpu, dr, kvm_register_read(vcpu, reg));
	}

out:
	return kvm_complete_insn_gp(vcpu, err);
}

static void vmx_sync_dirty_debug_regs(struct kvm_vcpu *vcpu)
{
	get_debugreg(vcpu->arch.db[0], 0);
	get_debugreg(vcpu->arch.db[1], 1);
	get_debugreg(vcpu->arch.db[2], 2);
	get_debugreg(vcpu->arch.db[3], 3);
	get_debugreg(vcpu->arch.dr6, 6);
	vcpu->arch.dr7 = vmcs_readl(GUEST_DR7);

	vcpu->arch.switch_db_regs &= ~KVM_DEBUGREG_WONT_EXIT;
	exec_controls_setbit(to_vmx(vcpu), CPU_BASED_MOV_DR_EXITING);

	/*
	 * exc_debug expects dr6 to be cleared after it runs, avoid that it sees
	 * a stale dr6 from the guest.
	 */
	set_debugreg(DR6_RESERVED, 6);
}

static void vmx_set_dr7(struct kvm_vcpu *vcpu, unsigned long val)
{
	vmcs_writel(GUEST_DR7, val);
}

static int handle_tpr_below_threshold(struct kvm_vcpu *vcpu)
{
	kvm_apic_update_ppr(vcpu);
	return 1;
}

static int handle_interrupt_window(struct kvm_vcpu *vcpu)
{
	exec_controls_clearbit(to_vmx(vcpu), CPU_BASED_INTR_WINDOW_EXITING);

	kvm_make_request(KVM_REQ_EVENT, vcpu);

	++vcpu->stat.irq_window_exits;
	return 1;
}

static int handle_invlpg(struct kvm_vcpu *vcpu)
{
	unsigned long exit_qualification = vmx_get_exit_qual(vcpu);

	kvm_mmu_invlpg(vcpu, exit_qualification);
	return kvm_skip_emulated_instruction(vcpu);
}

static int handle_apic_access(struct kvm_vcpu *vcpu)
{
	if (likely(fasteoi)) {
		unsigned long exit_qualification = vmx_get_exit_qual(vcpu);
		int access_type, offset;

		access_type = exit_qualification & APIC_ACCESS_TYPE;
		offset = exit_qualification & APIC_ACCESS_OFFSET;
		/*
		 * Sane guest uses MOV to write EOI, with written value
		 * not cared. So make a short-circuit here by avoiding
		 * heavy instruction emulation.
		 */
		if ((access_type == TYPE_LINEAR_APIC_INST_WRITE) &&
		    (offset == APIC_EOI)) {
			kvm_lapic_set_eoi(vcpu);
			return kvm_skip_emulated_instruction(vcpu);
		}
	}
	return kvm_emulate_instruction(vcpu, 0);
}

static int handle_apic_eoi_induced(struct kvm_vcpu *vcpu)
{
	unsigned long exit_qualification = vmx_get_exit_qual(vcpu);
	int vector = exit_qualification & 0xff;

	/* EOI-induced VM exit is trap-like and thus no need to adjust IP */
	kvm_apic_set_eoi_accelerated(vcpu, vector);
	return 1;
}

static int handle_apic_write(struct kvm_vcpu *vcpu)
{
	unsigned long exit_qualification = vmx_get_exit_qual(vcpu);

	/*
	 * APIC-write VM-Exit is trap-like, KVM doesn't need to advance RIP and
	 * hardware has done any necessary aliasing, offset adjustments, etc...
	 * for the access.  I.e. the correct value has already been  written to
	 * the vAPIC page for the correct 16-byte chunk.  KVM needs only to
	 * retrieve the register value and emulate the access.
	 */
	u32 offset = exit_qualification & 0xff0;

	kvm_apic_write_nodecode(vcpu, offset);
	return 1;
}

static int handle_task_switch(struct kvm_vcpu *vcpu)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	unsigned long exit_qualification;
	bool has_error_code = false;
	u32 error_code = 0;
	u16 tss_selector;
	int reason, type, idt_v, idt_index;

	idt_v = (vmx->idt_vectoring_info & VECTORING_INFO_VALID_MASK);
	idt_index = (vmx->idt_vectoring_info & VECTORING_INFO_VECTOR_MASK);
	type = (vmx->idt_vectoring_info & VECTORING_INFO_TYPE_MASK);

	exit_qualification = vmx_get_exit_qual(vcpu);

	reason = (u32)exit_qualification >> 30;
	if (reason == TASK_SWITCH_GATE && idt_v) {
		switch (type) {
		case INTR_TYPE_NMI_INTR:
			vcpu->arch.nmi_injected = false;
			vmx_set_nmi_mask(vcpu, true);
			break;
		case INTR_TYPE_EXT_INTR:
		case INTR_TYPE_SOFT_INTR:
			kvm_clear_interrupt_queue(vcpu);
			break;
		case INTR_TYPE_HARD_EXCEPTION:
			if (vmx->idt_vectoring_info &
			    VECTORING_INFO_DELIVER_CODE_MASK) {
				has_error_code = true;
				error_code =
					vmcs_read32(IDT_VECTORING_ERROR_CODE);
			}
			fallthrough;
		case INTR_TYPE_SOFT_EXCEPTION:
			kvm_clear_exception_queue(vcpu);
			break;
		default:
			break;
		}
	}
	tss_selector = exit_qualification;

	if (!idt_v || (type != INTR_TYPE_HARD_EXCEPTION &&
		       type != INTR_TYPE_EXT_INTR &&
		       type != INTR_TYPE_NMI_INTR))
		WARN_ON(!skip_emulated_instruction(vcpu));

	/*
	 * TODO: What about debug traps on tss switch?
	 *       Are we supposed to inject them and update dr6?
	 */
	return kvm_task_switch(vcpu, tss_selector,
			       type == INTR_TYPE_SOFT_INTR ? idt_index : -1,
			       reason, has_error_code, error_code);
}

static int handle_ept_violation(struct kvm_vcpu *vcpu)
{
	unsigned long exit_qualification;
	gpa_t gpa;
	u64 error_code;

	exit_qualification = vmx_get_exit_qual(vcpu);

	/*
	 * EPT violation happened while executing iret from NMI,
	 * "blocked by NMI" bit has to be set before next VM entry.
	 * There are errata that may cause this bit to not be set:
	 * AAK134, BY25.
	 */
	if (!(to_vmx(vcpu)->idt_vectoring_info & VECTORING_INFO_VALID_MASK) &&
			enable_vnmi &&
			(exit_qualification & INTR_INFO_UNBLOCK_NMI))
		vmcs_set_bits(GUEST_INTERRUPTIBILITY_INFO, GUEST_INTR_STATE_NMI);

	gpa = vmcs_read64(GUEST_PHYSICAL_ADDRESS);
	trace_kvm_page_fault(vcpu, gpa, exit_qualification);

	/* Is it a read fault? */
	error_code = (exit_qualification & EPT_VIOLATION_ACC_READ)
		     ? PFERR_USER_MASK : 0;
	/* Is it a write fault? */
	error_code |= (exit_qualification & EPT_VIOLATION_ACC_WRITE)
		      ? PFERR_WRITE_MASK : 0;
	/* Is it a fetch fault? */
	error_code |= (exit_qualification & EPT_VIOLATION_ACC_INSTR)
		      ? PFERR_FETCH_MASK : 0;
	/* ept page table entry is present? */
	error_code |= (exit_qualification & EPT_VIOLATION_RWX_MASK)
		      ? PFERR_PRESENT_MASK : 0;

	error_code |= (exit_qualification & EPT_VIOLATION_GVA_TRANSLATED) != 0 ?
	       PFERR_GUEST_FINAL_MASK : PFERR_GUEST_PAGE_MASK;

	vcpu->arch.exit_qualification = exit_qualification;

	/*
	 * Check that the GPA doesn't exceed physical memory limits, as that is
	 * a guest page fault.  We have to emulate the instruction here, because
	 * if the illegal address is that of a paging structure, then
	 * EPT_VIOLATION_ACC_WRITE bit is set.  Alternatively, if supported we
	 * would also use advanced VM-exit information for EPT violations to
	 * reconstruct the page fault error code.
	 */
	if (unlikely(allow_smaller_maxphyaddr && kvm_vcpu_is_illegal_gpa(vcpu, gpa)))
		return kvm_emulate_instruction(vcpu, 0);

	return kvm_mmu_page_fault(vcpu, gpa, error_code, NULL, 0);
}

static int handle_ept_misconfig(struct kvm_vcpu *vcpu)
{
	gpa_t gpa;

	if (!vmx_can_emulate_instruction(vcpu, EMULTYPE_PF, NULL, 0))
		return 1;

	/*
	 * A nested guest cannot optimize MMIO vmexits, because we have an
	 * nGPA here instead of the required GPA.
	 */
	gpa = vmcs_read64(GUEST_PHYSICAL_ADDRESS);
	if (!is_guest_mode(vcpu) &&
	    !kvm_io_bus_write(vcpu, KVM_FAST_MMIO_BUS, gpa, 0, NULL)) {
		trace_kvm_fast_mmio(gpa);
		return kvm_skip_emulated_instruction(vcpu);
	}

	return kvm_mmu_page_fault(vcpu, gpa, PFERR_RSVD_MASK, NULL, 0);
}

static int handle_nmi_window(struct kvm_vcpu *vcpu)
{
	if (KVM_BUG_ON(!enable_vnmi, vcpu->kvm))
		return -EIO;

	exec_controls_clearbit(to_vmx(vcpu), CPU_BASED_NMI_WINDOW_EXITING);
	++vcpu->stat.nmi_window_exits;
	kvm_make_request(KVM_REQ_EVENT, vcpu);

	return 1;
}

static bool vmx_emulation_required_with_pending_exception(struct kvm_vcpu *vcpu)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);

	return vmx->emulation_required && !vmx->rmode.vm86_active &&
	       (kvm_is_exception_pending(vcpu) || vcpu->arch.exception.injected);
}

static int handle_invalid_guest_state(struct kvm_vcpu *vcpu)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	bool intr_window_requested;
	unsigned count = 130;

	intr_window_requested = exec_controls_get(vmx) &
				CPU_BASED_INTR_WINDOW_EXITING;

	while (vmx->emulation_required && count-- != 0) {
		if (intr_window_requested && !vmx_interrupt_blocked(vcpu))
			return handle_interrupt_window(&vmx->vcpu);

		if (kvm_test_request(KVM_REQ_EVENT, vcpu))
			return 1;

		if (!kvm_emulate_instruction(vcpu, 0))
			return 0;

		if (vmx_emulation_required_with_pending_exception(vcpu)) {
			kvm_prepare_emulation_failure_exit(vcpu);
			return 0;
		}

		if (vcpu->arch.halt_request) {
			vcpu->arch.halt_request = 0;
			return kvm_emulate_halt_noskip(vcpu);
		}

		/*
		 * Note, return 1 and not 0, vcpu_run() will invoke
		 * xfer_to_guest_mode() which will create a proper return
		 * code.
		 */
		if (__xfer_to_guest_mode_work_pending())
			return 1;
	}

	return 1;
}

static int vmx_vcpu_pre_run(struct kvm_vcpu *vcpu)
{
	if (vmx_emulation_required_with_pending_exception(vcpu)) {
		kvm_prepare_emulation_failure_exit(vcpu);
		return 0;
	}

	return 1;
}

static void grow_ple_window(struct kvm_vcpu *vcpu)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	unsigned int old = vmx->ple_window;

	vmx->ple_window = __grow_ple_window(old, ple_window,
					    ple_window_grow,
					    ple_window_max);

	if (vmx->ple_window != old) {
		vmx->ple_window_dirty = true;
		trace_kvm_ple_window_update(vcpu->vcpu_id,
					    vmx->ple_window, old);
	}
}

static void shrink_ple_window(struct kvm_vcpu *vcpu)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	unsigned int old = vmx->ple_window;

	vmx->ple_window = __shrink_ple_window(old, ple_window,
					      ple_window_shrink,
					      ple_window);

	if (vmx->ple_window != old) {
		vmx->ple_window_dirty = true;
		trace_kvm_ple_window_update(vcpu->vcpu_id,
					    vmx->ple_window, old);
	}
}

/*
 * Indicate a busy-waiting vcpu in spinlock. We do not enable the PAUSE
 * exiting, so only get here on cpu with PAUSE-Loop-Exiting.
 */
static int handle_pause(struct kvm_vcpu *vcpu)
{
	if (!kvm_pause_in_guest(vcpu->kvm))
		grow_ple_window(vcpu);

	/*
	 * Intel sdm vol3 ch-25.1.3 says: The "PAUSE-loop exiting"
	 * VM-execution control is ignored if CPL > 0. OTOH, KVM
	 * never set PAUSE_EXITING and just set PLE if supported,
	 * so the vcpu must be CPL=0 if it gets a PAUSE exit.
	 */
	kvm_vcpu_on_spin(vcpu, true);
	return kvm_skip_emulated_instruction(vcpu);
}

static int handle_monitor_trap(struct kvm_vcpu *vcpu)
{
	return 1;
}

static int handle_invpcid(struct kvm_vcpu *vcpu)
{
	u32 vmx_instruction_info;
	unsigned long type;
	gva_t gva;
	struct {
		u64 pcid;
		u64 gla;
	} operand;
	int gpr_index;

	if (!guest_cpuid_has(vcpu, X86_FEATURE_INVPCID)) {
		kvm_queue_exception(vcpu, UD_VECTOR);
		return 1;
	}

	vmx_instruction_info = vmcs_read32(VMX_INSTRUCTION_INFO);
	gpr_index = vmx_get_instr_info_reg2(vmx_instruction_info);
	type = kvm_register_read(vcpu, gpr_index);

	/* According to the Intel instruction reference, the memory operand
	 * is read even if it isn't needed (e.g., for type==all)
	 */
	if (get_vmx_mem_address(vcpu, vmx_get_exit_qual(vcpu),
				vmx_instruction_info, false,
				sizeof(operand), &gva))
		return 1;

	return kvm_handle_invpcid(vcpu, type, gva);
}

static int handle_pml_full(struct kvm_vcpu *vcpu)
{
	unsigned long exit_qualification;

	trace_kvm_pml_full(vcpu->vcpu_id);

	exit_qualification = vmx_get_exit_qual(vcpu);

	/*
	 * PML buffer FULL happened while executing iret from NMI,
	 * "blocked by NMI" bit has to be set before next VM entry.
	 */
	if (!(to_vmx(vcpu)->idt_vectoring_info & VECTORING_INFO_VALID_MASK) &&
			enable_vnmi &&
			(exit_qualification & INTR_INFO_UNBLOCK_NMI))
		vmcs_set_bits(GUEST_INTERRUPTIBILITY_INFO,
				GUEST_INTR_STATE_NMI);

	/*
	 * PML buffer already flushed at beginning of VMEXIT. Nothing to do
	 * here.., and there's no userspace involvement needed for PML.
	 */
	return 1;
}

static fastpath_t handle_fastpath_preemption_timer(struct kvm_vcpu *vcpu)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);

	if (!vmx->req_immediate_exit &&
	    !unlikely(vmx->loaded_vmcs->hv_timer_soft_disabled)) {
		kvm_lapic_expired_hv_timer(vcpu);
		return EXIT_FASTPATH_REENTER_GUEST;
	}

	return EXIT_FASTPATH_NONE;
}

static int handle_preemption_timer(struct kvm_vcpu *vcpu)
{
	handle_fastpath_preemption_timer(vcpu);
	return 1;
}

/*
 * When nested=0, all VMX instruction VM Exits filter here.  The handlers
 * are overwritten by nested_vmx_setup() when nested=1.
 */
static int handle_vmx_instruction(struct kvm_vcpu *vcpu)
{
	kvm_queue_exception(vcpu, UD_VECTOR);
	return 1;
}

#ifndef CONFIG_X86_SGX_KVM
static int handle_encls(struct kvm_vcpu *vcpu)
{
	/*
	 * SGX virtualization is disabled.  There is no software enable bit for
	 * SGX, so KVM intercepts all ENCLS leafs and injects a #UD to prevent
	 * the guest from executing ENCLS (when SGX is supported by hardware).
	 */
	kvm_queue_exception(vcpu, UD_VECTOR);
	return 1;
}
#endif /* CONFIG_X86_SGX_KVM */

static int handle_bus_lock_vmexit(struct kvm_vcpu *vcpu)
{
	/*
	 * Hardware may or may not set the BUS_LOCK_DETECTED flag on BUS_LOCK
	 * VM-Exits. Unconditionally set the flag here and leave the handling to
	 * vmx_handle_exit().
	 */
	to_vmx(vcpu)->exit_reason.bus_lock_detected = true;
	return 1;
}

static int handle_notify(struct kvm_vcpu *vcpu)
{
	unsigned long exit_qual = vmx_get_exit_qual(vcpu);
	bool context_invalid = exit_qual & NOTIFY_VM_CONTEXT_INVALID;

	++vcpu->stat.notify_window_exits;

	/*
	 * Notify VM exit happened while executing iret from NMI,
	 * "blocked by NMI" bit has to be set before next VM entry.
	 */
	if (enable_vnmi && (exit_qual & INTR_INFO_UNBLOCK_NMI))
		vmcs_set_bits(GUEST_INTERRUPTIBILITY_INFO,
			      GUEST_INTR_STATE_NMI);

	if (vcpu->kvm->arch.notify_vmexit_flags & KVM_X86_NOTIFY_VMEXIT_USER ||
	    context_invalid) {
		vcpu->run->exit_reason = KVM_EXIT_NOTIFY;
		vcpu->run->notify.flags = context_invalid ?
					  KVM_NOTIFY_CONTEXT_INVALID : 0;
		return 0;
	}

	return 1;
}

/*
 * The exit handlers return 1 if the exit was handled fully and guest execution
 * may resume.  Otherwise they set the kvm_run parameter to indicate what needs
 * to be done to userspace and return 0.
 */
static int (*kvm_vmx_exit_handlers[])(struct kvm_vcpu *vcpu) = {
	[EXIT_REASON_EXCEPTION_NMI]           = handle_exception_nmi,
	[EXIT_REASON_EXTERNAL_INTERRUPT]      = handle_external_interrupt,
	[EXIT_REASON_TRIPLE_FAULT]            = handle_triple_fault,
	[EXIT_REASON_NMI_WINDOW]	      = handle_nmi_window,
	[EXIT_REASON_IO_INSTRUCTION]          = handle_io,
	[EXIT_REASON_CR_ACCESS]               = handle_cr,
	[EXIT_REASON_DR_ACCESS]               = handle_dr,
	[EXIT_REASON_CPUID]                   = kvm_emulate_cpuid,
	[EXIT_REASON_MSR_READ]                = kvm_emulate_rdmsr,
	[EXIT_REASON_MSR_WRITE]               = kvm_emulate_wrmsr,
	[EXIT_REASON_INTERRUPT_WINDOW]        = handle_interrupt_window,
	[EXIT_REASON_HLT]                     = kvm_emulate_halt,
	[EXIT_REASON_INVD]		      = kvm_emulate_invd,
	[EXIT_REASON_INVLPG]		      = handle_invlpg,
	[EXIT_REASON_RDPMC]                   = kvm_emulate_rdpmc,
	[EXIT_REASON_VMCALL]                  = kvm_emulate_hypercall,
	[EXIT_REASON_VMCLEAR]		      = handle_vmx_instruction,
	[EXIT_REASON_VMLAUNCH]		      = handle_vmx_instruction,
	[EXIT_REASON_VMPTRLD]		      = handle_vmx_instruction,
	[EXIT_REASON_VMPTRST]		      = handle_vmx_instruction,
	[EXIT_REASON_VMREAD]		      = handle_vmx_instruction,
	[EXIT_REASON_VMRESUME]		      = handle_vmx_instruction,
	[EXIT_REASON_VMWRITE]		      = handle_vmx_instruction,
	[EXIT_REASON_VMOFF]		      = handle_vmx_instruction,
	[EXIT_REASON_VMON]		      = handle_vmx_instruction,
	[EXIT_REASON_TPR_BELOW_THRESHOLD]     = handle_tpr_below_threshold,
	[EXIT_REASON_APIC_ACCESS]             = handle_apic_access,
	[EXIT_REASON_APIC_WRITE]              = handle_apic_write,
	[EXIT_REASON_EOI_INDUCED]             = handle_apic_eoi_induced,
	[EXIT_REASON_WBINVD]                  = kvm_emulate_wbinvd,
	[EXIT_REASON_XSETBV]                  = kvm_emulate_xsetbv,
	[EXIT_REASON_TASK_SWITCH]             = handle_task_switch,
	[EXIT_REASON_MCE_DURING_VMENTRY]      = handle_machine_check,
	[EXIT_REASON_GDTR_IDTR]		      = handle_desc,
	[EXIT_REASON_LDTR_TR]		      = handle_desc,
	[EXIT_REASON_EPT_VIOLATION]	      = handle_ept_violation,
	[EXIT_REASON_EPT_MISCONFIG]           = handle_ept_misconfig,
	[EXIT_REASON_PAUSE_INSTRUCTION]       = handle_pause,
	[EXIT_REASON_MWAIT_INSTRUCTION]	      = kvm_emulate_mwait,
	[EXIT_REASON_MONITOR_TRAP_FLAG]       = handle_monitor_trap,
	[EXIT_REASON_MONITOR_INSTRUCTION]     = kvm_emulate_monitor,
	[EXIT_REASON_INVEPT]                  = handle_vmx_instruction,
	[EXIT_REASON_INVVPID]                 = handle_vmx_instruction,
	[EXIT_REASON_RDRAND]                  = kvm_handle_invalid_op,
	[EXIT_REASON_RDSEED]                  = kvm_handle_invalid_op,
	[EXIT_REASON_PML_FULL]		      = handle_pml_full,
	[EXIT_REASON_INVPCID]                 = handle_invpcid,
	[EXIT_REASON_VMFUNC]		      = handle_vmx_instruction,
	[EXIT_REASON_PREEMPTION_TIMER]	      = handle_preemption_timer,
	[EXIT_REASON_ENCLS]		      = handle_encls,
	[EXIT_REASON_BUS_LOCK]                = handle_bus_lock_vmexit,
	[EXIT_REASON_NOTIFY]		      = handle_notify,
};

static const int kvm_vmx_max_exit_handlers =
	ARRAY_SIZE(kvm_vmx_exit_handlers);

static void vmx_get_exit_info(struct kvm_vcpu *vcpu, u32 *reason,
			      u64 *info1, u64 *info2,
			      u32 *intr_info, u32 *error_code)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);

	*reason = vmx->exit_reason.full;
	*info1 = vmx_get_exit_qual(vcpu);
	if (!(vmx->exit_reason.failed_vmentry)) {
		*info2 = vmx->idt_vectoring_info;
		*intr_info = vmx_get_intr_info(vcpu);
		if (is_exception_with_error_code(*intr_info))
			*error_code = vmcs_read32(VM_EXIT_INTR_ERROR_CODE);
		else
			*error_code = 0;
	} else {
		*info2 = 0;
		*intr_info = 0;
		*error_code = 0;
	}
}

static void vmx_destroy_pml_buffer(struct vcpu_vmx *vmx)
{
	if (vmx->pml_pg) {
		__free_page(vmx->pml_pg);
		vmx->pml_pg = NULL;
	}
}

static void vmx_flush_pml_buffer(struct kvm_vcpu *vcpu)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	u64 *pml_buf;
	u16 pml_idx;

	pml_idx = vmcs_read16(GUEST_PML_INDEX);

	/* Do nothing if PML buffer is empty */
	if (pml_idx == (PML_ENTITY_NUM - 1))
		return;

	/* PML index always points to next available PML buffer entity */
	if (pml_idx >= PML_ENTITY_NUM)
		pml_idx = 0;
	else
		pml_idx++;

	pml_buf = page_address(vmx->pml_pg);
	for (; pml_idx < PML_ENTITY_NUM; pml_idx++) {
		u64 gpa;

		gpa = pml_buf[pml_idx];
		WARN_ON(gpa & (PAGE_SIZE - 1));
		kvm_vcpu_mark_page_dirty(vcpu, gpa >> PAGE_SHIFT);
	}

	/* reset PML index */
	vmcs_write16(GUEST_PML_INDEX, PML_ENTITY_NUM - 1);
}

static void vmx_dump_sel(char *name, uint32_t sel)
{
	pr_err("%s sel=0x%04x, attr=0x%05x, limit=0x%08x, base=0x%016lx\n",
	       name, vmcs_read16(sel),
	       vmcs_read32(sel + GUEST_ES_AR_BYTES - GUEST_ES_SELECTOR),
	       vmcs_read32(sel + GUEST_ES_LIMIT - GUEST_ES_SELECTOR),
	       vmcs_readl(sel + GUEST_ES_BASE - GUEST_ES_SELECTOR));
}

static void vmx_dump_dtsel(char *name, uint32_t limit)
{
	pr_err("%s                           limit=0x%08x, base=0x%016lx\n",
	       name, vmcs_read32(limit),
	       vmcs_readl(limit + GUEST_GDTR_BASE - GUEST_GDTR_LIMIT));
}

static void vmx_dump_msrs(char *name, struct vmx_msrs *m)
{
	unsigned int i;
	struct vmx_msr_entry *e;

	pr_err("MSR %s:\n", name);
	for (i = 0, e = m->val; i < m->nr; ++i, ++e)
		pr_err("  %2d: msr=0x%08x value=0x%016llx\n", i, e->index, e->value);
}

void dump_vmcs(struct kvm_vcpu *vcpu)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	u32 vmentry_ctl, vmexit_ctl;
	u32 cpu_based_exec_ctrl, pin_based_exec_ctrl, secondary_exec_control;
	u64 tertiary_exec_control;
	unsigned long cr4;
	int efer_slot;

	if (!dump_invalid_vmcs) {
		pr_warn_ratelimited("set kvm_intel.dump_invalid_vmcs=1 to dump internal KVM state.\n");
		return;
	}

	vmentry_ctl = vmcs_read32(VM_ENTRY_CONTROLS);
	vmexit_ctl = vmcs_read32(VM_EXIT_CONTROLS);
	cpu_based_exec_ctrl = vmcs_read32(CPU_BASED_VM_EXEC_CONTROL);
	pin_based_exec_ctrl = vmcs_read32(PIN_BASED_VM_EXEC_CONTROL);
	cr4 = vmcs_readl(GUEST_CR4);

	if (cpu_has_secondary_exec_ctrls())
		secondary_exec_control = vmcs_read32(SECONDARY_VM_EXEC_CONTROL);
	else
		secondary_exec_control = 0;

	if (cpu_has_tertiary_exec_ctrls())
		tertiary_exec_control = vmcs_read64(TERTIARY_VM_EXEC_CONTROL);
	else
		tertiary_exec_control = 0;

	pr_err("VMCS %p, last attempted VM-entry on CPU %d\n",
	       vmx->loaded_vmcs->vmcs, vcpu->arch.last_vmentry_cpu);
	pr_err("*** Guest State ***\n");
	pr_err("CR0: actual=0x%016lx, shadow=0x%016lx, gh_mask=%016lx\n",
	       vmcs_readl(GUEST_CR0), vmcs_readl(CR0_READ_SHADOW),
	       vmcs_readl(CR0_GUEST_HOST_MASK));
	pr_err("CR4: actual=0x%016lx, shadow=0x%016lx, gh_mask=%016lx\n",
	       cr4, vmcs_readl(CR4_READ_SHADOW), vmcs_readl(CR4_GUEST_HOST_MASK));
	pr_err("CR3 = 0x%016lx\n", vmcs_readl(GUEST_CR3));
	if (cpu_has_vmx_ept()) {
		pr_err("PDPTR0 = 0x%016llx  PDPTR1 = 0x%016llx\n",
		       vmcs_read64(GUEST_PDPTR0), vmcs_read64(GUEST_PDPTR1));
		pr_err("PDPTR2 = 0x%016llx  PDPTR3 = 0x%016llx\n",
		       vmcs_read64(GUEST_PDPTR2), vmcs_read64(GUEST_PDPTR3));
	}
	pr_err("RSP = 0x%016lx  RIP = 0x%016lx\n",
	       vmcs_readl(GUEST_RSP), vmcs_readl(GUEST_RIP));
	pr_err("RFLAGS=0x%08lx         DR7 = 0x%016lx\n",
	       vmcs_readl(GUEST_RFLAGS), vmcs_readl(GUEST_DR7));
	pr_err("Sysenter RSP=%016lx CS:RIP=%04x:%016lx\n",
	       vmcs_readl(GUEST_SYSENTER_ESP),
	       vmcs_read32(GUEST_SYSENTER_CS), vmcs_readl(GUEST_SYSENTER_EIP));
	vmx_dump_sel("CS:  ", GUEST_CS_SELECTOR);
	vmx_dump_sel("DS:  ", GUEST_DS_SELECTOR);
	vmx_dump_sel("SS:  ", GUEST_SS_SELECTOR);
	vmx_dump_sel("ES:  ", GUEST_ES_SELECTOR);
	vmx_dump_sel("FS:  ", GUEST_FS_SELECTOR);
	vmx_dump_sel("GS:  ", GUEST_GS_SELECTOR);
	vmx_dump_dtsel("GDTR:", GUEST_GDTR_LIMIT);
	vmx_dump_sel("LDTR:", GUEST_LDTR_SELECTOR);
	vmx_dump_dtsel("IDTR:", GUEST_IDTR_LIMIT);
	vmx_dump_sel("TR:  ", GUEST_TR_SELECTOR);
	efer_slot = vmx_find_loadstore_msr_slot(&vmx->msr_autoload.guest, MSR_EFER);
	if (vmentry_ctl & VM_ENTRY_LOAD_IA32_EFER)
		pr_err("EFER= 0x%016llx\n", vmcs_read64(GUEST_IA32_EFER));
	else if (efer_slot >= 0)
		pr_err("EFER= 0x%016llx (autoload)\n",
		       vmx->msr_autoload.guest.val[efer_slot].value);
	else if (vmentry_ctl & VM_ENTRY_IA32E_MODE)
		pr_err("EFER= 0x%016llx (effective)\n",
		       vcpu->arch.efer | (EFER_LMA | EFER_LME));
	else
		pr_err("EFER= 0x%016llx (effective)\n",
		       vcpu->arch.efer & ~(EFER_LMA | EFER_LME));
	if (vmentry_ctl & VM_ENTRY_LOAD_IA32_PAT)
		pr_err("PAT = 0x%016llx\n", vmcs_read64(GUEST_IA32_PAT));
	pr_err("DebugCtl = 0x%016llx  DebugExceptions = 0x%016lx\n",
	       vmcs_read64(GUEST_IA32_DEBUGCTL),
	       vmcs_readl(GUEST_PENDING_DBG_EXCEPTIONS));
	if (cpu_has_load_perf_global_ctrl() &&
	    vmentry_ctl & VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL)
		pr_err("PerfGlobCtl = 0x%016llx\n",
		       vmcs_read64(GUEST_IA32_PERF_GLOBAL_CTRL));
	if (vmentry_ctl & VM_ENTRY_LOAD_BNDCFGS)
		pr_err("BndCfgS = 0x%016llx\n", vmcs_read64(GUEST_BNDCFGS));
	pr_err("Interruptibility = %08x  ActivityState = %08x\n",
	       vmcs_read32(GUEST_INTERRUPTIBILITY_INFO),
	       vmcs_read32(GUEST_ACTIVITY_STATE));
	if (secondary_exec_control & SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY)
		pr_err("InterruptStatus = %04x\n",
		       vmcs_read16(GUEST_INTR_STATUS));
	if (vmcs_read32(VM_ENTRY_MSR_LOAD_COUNT) > 0)
		vmx_dump_msrs("guest autoload", &vmx->msr_autoload.guest);
	if (vmcs_read32(VM_EXIT_MSR_STORE_COUNT) > 0)
		vmx_dump_msrs("guest autostore", &vmx->msr_autostore.guest);

	pr_err("*** Host State ***\n");
	pr_err("RIP = 0x%016lx  RSP = 0x%016lx\n",
	       vmcs_readl(HOST_RIP), vmcs_readl(HOST_RSP));
	pr_err("CS=%04x SS=%04x DS=%04x ES=%04x FS=%04x GS=%04x TR=%04x\n",
	       vmcs_read16(HOST_CS_SELECTOR), vmcs_read16(HOST_SS_SELECTOR),
	       vmcs_read16(HOST_DS_SELECTOR), vmcs_read16(HOST_ES_SELECTOR),
	       vmcs_read16(HOST_FS_SELECTOR), vmcs_read16(HOST_GS_SELECTOR),
	       vmcs_read16(HOST_TR_SELECTOR));
	pr_err("FSBase=%016lx GSBase=%016lx TRBase=%016lx\n",
	       vmcs_readl(HOST_FS_BASE), vmcs_readl(HOST_GS_BASE),
	       vmcs_readl(HOST_TR_BASE));
	pr_err("GDTBase=%016lx IDTBase=%016lx\n",
	       vmcs_readl(HOST_GDTR_BASE), vmcs_readl(HOST_IDTR_BASE));
	pr_err("CR0=%016lx CR3=%016lx CR4=%016lx\n",
	       vmcs_readl(HOST_CR0), vmcs_readl(HOST_CR3),
	       vmcs_readl(HOST_CR4));
	pr_err("Sysenter RSP=%016lx CS:RIP=%04x:%016lx\n",
	       vmcs_readl(HOST_IA32_SYSENTER_ESP),
	       vmcs_read32(HOST_IA32_SYSENTER_CS),
	       vmcs_readl(HOST_IA32_SYSENTER_EIP));
	if (vmexit_ctl & VM_EXIT_LOAD_IA32_EFER)
		pr_err("EFER= 0x%016llx\n", vmcs_read64(HOST_IA32_EFER));
	if (vmexit_ctl & VM_EXIT_LOAD_IA32_PAT)
		pr_err("PAT = 0x%016llx\n", vmcs_read64(HOST_IA32_PAT));
	if (cpu_has_load_perf_global_ctrl() &&
	    vmexit_ctl & VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL)
		pr_err("PerfGlobCtl = 0x%016llx\n",
		       vmcs_read64(HOST_IA32_PERF_GLOBAL_CTRL));
	if (vmcs_read32(VM_EXIT_MSR_LOAD_COUNT) > 0)
		vmx_dump_msrs("host autoload", &vmx->msr_autoload.host);

	pr_err("*** Control State ***\n");
	pr_err("CPUBased=0x%08x SecondaryExec=0x%08x TertiaryExec=0x%016llx\n",
	       cpu_based_exec_ctrl, secondary_exec_control, tertiary_exec_control);
	pr_err("PinBased=0x%08x EntryControls=%08x ExitControls=%08x\n",
	       pin_based_exec_ctrl, vmentry_ctl, vmexit_ctl);
	pr_err("ExceptionBitmap=%08x PFECmask=%08x PFECmatch=%08x\n",
	       vmcs_read32(EXCEPTION_BITMAP),
	       vmcs_read32(PAGE_FAULT_ERROR_CODE_MASK),
	       vmcs_read32(PAGE_FAULT_ERROR_CODE_MATCH));
	pr_err("VMEntry: intr_info=%08x errcode=%08x ilen=%08x\n",
	       vmcs_read32(VM_ENTRY_INTR_INFO_FIELD),
	       vmcs_read32(VM_ENTRY_EXCEPTION_ERROR_CODE),
	       vmcs_read32(VM_ENTRY_INSTRUCTION_LEN));
	pr_err("VMExit: intr_info=%08x errcode=%08x ilen=%08x\n",
	       vmcs_read32(VM_EXIT_INTR_INFO),
	       vmcs_read32(VM_EXIT_INTR_ERROR_CODE),
	       vmcs_read32(VM_EXIT_INSTRUCTION_LEN));
	pr_err("        reason=%08x qualification=%016lx\n",
	       vmcs_read32(VM_EXIT_REASON), vmcs_readl(EXIT_QUALIFICATION));
	pr_err("IDTVectoring: info=%08x errcode=%08x\n",
	       vmcs_read32(IDT_VECTORING_INFO_FIELD),
	       vmcs_read32(IDT_VECTORING_ERROR_CODE));
	pr_err("TSC Offset = 0x%016llx\n", vmcs_read64(TSC_OFFSET));
	if (secondary_exec_control & SECONDARY_EXEC_TSC_SCALING)
		pr_err("TSC Multiplier = 0x%016llx\n",
		       vmcs_read64(TSC_MULTIPLIER));
	if (cpu_based_exec_ctrl & CPU_BASED_TPR_SHADOW) {
		if (secondary_exec_control & SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY) {
			u16 status = vmcs_read16(GUEST_INTR_STATUS);
			pr_err("SVI|RVI = %02x|%02x ", status >> 8, status & 0xff);
		}
		pr_cont("TPR Threshold = 0x%02x\n", vmcs_read32(TPR_THRESHOLD));
		if (secondary_exec_control & SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES)
			pr_err("APIC-access addr = 0x%016llx ", vmcs_read64(APIC_ACCESS_ADDR));
		pr_cont("virt-APIC addr = 0x%016llx\n", vmcs_read64(VIRTUAL_APIC_PAGE_ADDR));
	}
	if (pin_based_exec_ctrl & PIN_BASED_POSTED_INTR)
		pr_err("PostedIntrVec = 0x%02x\n", vmcs_read16(POSTED_INTR_NV));
	if ((secondary_exec_control & SECONDARY_EXEC_ENABLE_EPT))
		pr_err("EPT pointer = 0x%016llx\n", vmcs_read64(EPT_POINTER));
	if (secondary_exec_control & SECONDARY_EXEC_PAUSE_LOOP_EXITING)
		pr_err("PLE Gap=%08x Window=%08x\n",
		       vmcs_read32(PLE_GAP), vmcs_read32(PLE_WINDOW));
	if (secondary_exec_control & SECONDARY_EXEC_ENABLE_VPID)
		pr_err("Virtual processor ID = 0x%04x\n",
		       vmcs_read16(VIRTUAL_PROCESSOR_ID));
}

/*
 * The guest has exited.  See if we can fix it or if we need userspace
 * assistance.
 */
static int __vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	union vmx_exit_reason exit_reason = vmx->exit_reason;
	u32 vectoring_info = vmx->idt_vectoring_info;
	u16 exit_handler_index;

	/*
	 * Flush logged GPAs PML buffer, this will make dirty_bitmap more
	 * updated. Another good is, in kvm_vm_ioctl_get_dirty_log, before
	 * querying dirty_bitmap, we only need to kick all vcpus out of guest
	 * mode as if vcpus is in root mode, the PML buffer must has been
	 * flushed already.  Note, PML is never enabled in hardware while
	 * running L2.
	 */
	if (enable_pml && !is_guest_mode(vcpu))
		vmx_flush_pml_buffer(vcpu);

	/*
	 * KVM should never reach this point with a pending nested VM-Enter.
	 * More specifically, short-circuiting VM-Entry to emulate L2 due to
	 * invalid guest state should never happen as that means KVM knowingly
	 * allowed a nested VM-Enter with an invalid vmcs12.  More below.
	 */
	if (KVM_BUG_ON(vmx->nested.nested_run_pending, vcpu->kvm))
		return -EIO;

	if (is_guest_mode(vcpu)) {
		/*
		 * PML is never enabled when running L2, bail immediately if a
		 * PML full exit occurs as something is horribly wrong.
		 */
		if (exit_reason.basic == EXIT_REASON_PML_FULL)
			goto unexpected_vmexit;

		/*
		 * The host physical addresses of some pages of guest memory
		 * are loaded into the vmcs02 (e.g. vmcs12's Virtual APIC
		 * Page). The CPU may write to these pages via their host
		 * physical address while L2 is running, bypassing any
		 * address-translation-based dirty tracking (e.g. EPT write
		 * protection).
		 *
		 * Mark them dirty on every exit from L2 to prevent them from
		 * getting out of sync with dirty tracking.
		 */
		nested_mark_vmcs12_pages_dirty(vcpu);

		/*
		 * Synthesize a triple fault if L2 state is invalid.  In normal
		 * operation, nested VM-Enter rejects any attempt to enter L2
		 * with invalid state.  However, those checks are skipped if
		 * state is being stuffed via RSM or KVM_SET_NESTED_STATE.  If
		 * L2 state is invalid, it means either L1 modified SMRAM state
		 * or userspace provided bad state.  Synthesize TRIPLE_FAULT as
		 * doing so is architecturally allowed in the RSM case, and is
		 * the least awful solution for the userspace case without
		 * risking false positives.
		 */
		if (vmx->emulation_required) {
			nested_vmx_vmexit(vcpu, EXIT_REASON_TRIPLE_FAULT, 0, 0);
			return 1;
		}

		if (nested_vmx_reflect_vmexit(vcpu))
			return 1;
	}

	/* If guest state is invalid, start emulating.  L2 is handled above. */
	if (vmx->emulation_required)
		return handle_invalid_guest_state(vcpu);

	if (exit_reason.failed_vmentry) {
		dump_vmcs(vcpu);
		vcpu->run->exit_reason = KVM_EXIT_FAIL_ENTRY;
		vcpu->run->fail_entry.hardware_entry_failure_reason
			= exit_reason.full;
		vcpu->run->fail_entry.cpu = vcpu->arch.last_vmentry_cpu;
		return 0;
	}

	if (unlikely(vmx->fail)) {
		dump_vmcs(vcpu);
		vcpu->run->exit_reason = KVM_EXIT_FAIL_ENTRY;
		vcpu->run->fail_entry.hardware_entry_failure_reason
			= vmcs_read32(VM_INSTRUCTION_ERROR);
		vcpu->run->fail_entry.cpu = vcpu->arch.last_vmentry_cpu;
		return 0;
	}

	/*
	 * Note:
	 * Do not try to fix EXIT_REASON_EPT_MISCONFIG if it caused by
	 * delivery event since it indicates guest is accessing MMIO.
	 * The vm-exit can be triggered again after return to guest that
	 * will cause infinite loop.
	 */
	if ((vectoring_info & VECTORING_INFO_VALID_MASK) &&
	    (exit_reason.basic != EXIT_REASON_EXCEPTION_NMI &&
	     exit_reason.basic != EXIT_REASON_EPT_VIOLATION &&
	     exit_reason.basic != EXIT_REASON_PML_FULL &&
	     exit_reason.basic != EXIT_REASON_APIC_ACCESS &&
	     exit_reason.basic != EXIT_REASON_TASK_SWITCH &&
	     exit_reason.basic != EXIT_REASON_NOTIFY)) {
		int ndata = 3;

		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
		vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_DELIVERY_EV;
		vcpu->run->internal.data[0] = vectoring_info;
		vcpu->run->internal.data[1] = exit_reason.full;
		vcpu->run->internal.data[2] = vcpu->arch.exit_qualification;
		if (exit_reason.basic == EXIT_REASON_EPT_MISCONFIG) {
			vcpu->run->internal.data[ndata++] =
				vmcs_read64(GUEST_PHYSICAL_ADDRESS);
		}
		vcpu->run->internal.data[ndata++] = vcpu->arch.last_vmentry_cpu;
		vcpu->run->internal.ndata = ndata;
		return 0;
	}

	if (unlikely(!enable_vnmi &&
		     vmx->loaded_vmcs->soft_vnmi_blocked)) {
		if (!vmx_interrupt_blocked(vcpu)) {
			vmx->loaded_vmcs->soft_vnmi_blocked = 0;
		} else if (vmx->loaded_vmcs->vnmi_blocked_time > 1000000000LL &&
			   vcpu->arch.nmi_pending) {
			/*
			 * This CPU don't support us in finding the end of an
			 * NMI-blocked window if the guest runs with IRQs
			 * disabled. So we pull the trigger after 1 s of
			 * futile waiting, but inform the user about this.
			 */
			printk(KERN_WARNING "%s: Breaking out of NMI-blocked "
			       "state on VCPU %d after 1 s timeout\n",
			       __func__, vcpu->vcpu_id);
			vmx->loaded_vmcs->soft_vnmi_blocked = 0;
		}
	}

	if (exit_fastpath != EXIT_FASTPATH_NONE)
		return 1;

	if (exit_reason.basic >= kvm_vmx_max_exit_handlers)
		goto unexpected_vmexit;
#ifdef CONFIG_RETPOLINE
	if (exit_reason.basic == EXIT_REASON_MSR_WRITE)
		return kvm_emulate_wrmsr(vcpu);
	else if (exit_reason.basic == EXIT_REASON_PREEMPTION_TIMER)
		return handle_preemption_timer(vcpu);
	else if (exit_reason.basic == EXIT_REASON_INTERRUPT_WINDOW)
		return handle_interrupt_window(vcpu);
	else if (exit_reason.basic == EXIT_REASON_EXTERNAL_INTERRUPT)
		return handle_external_interrupt(vcpu);
	else if (exit_reason.basic == EXIT_REASON_HLT)
		return kvm_emulate_halt(vcpu);
	else if (exit_reason.basic == EXIT_REASON_EPT_MISCONFIG)
		return handle_ept_misconfig(vcpu);
#endif

	exit_handler_index = array_index_nospec((u16)exit_reason.basic,
						kvm_vmx_max_exit_handlers);
	if (!kvm_vmx_exit_handlers[exit_handler_index])
		goto unexpected_vmexit;

	return kvm_vmx_exit_handlers[exit_handler_index](vcpu);

unexpected_vmexit:
	vcpu_unimpl(vcpu, "vmx: unexpected exit reason 0x%x\n",
		    exit_reason.full);
	dump_vmcs(vcpu);
	vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
	vcpu->run->internal.suberror =
			KVM_INTERNAL_ERROR_UNEXPECTED_EXIT_REASON;
	vcpu->run->internal.ndata = 2;
	vcpu->run->internal.data[0] = exit_reason.full;
	vcpu->run->internal.data[1] = vcpu->arch.last_vmentry_cpu;
	return 0;
}

static int vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath)
{
	int ret = __vmx_handle_exit(vcpu, exit_fastpath);

	/*
	 * Exit to user space when bus lock detected to inform that there is
	 * a bus lock in guest.
	 */
	if (to_vmx(vcpu)->exit_reason.bus_lock_detected) {
		if (ret > 0)
			vcpu->run->exit_reason = KVM_EXIT_X86_BUS_LOCK;

		vcpu->run->flags |= KVM_RUN_X86_BUS_LOCK;
		return 0;
	}
	return ret;
}

/*
 * Software based L1D cache flush which is used when microcode providing
 * the cache control MSR is not loaded.
 *
 * The L1D cache is 32 KiB on Nehalem and later microarchitectures, but to
 * flush it is required to read in 64 KiB because the replacement algorithm
 * is not exactly LRU. This could be sized at runtime via topology
 * information but as all relevant affected CPUs have 32KiB L1D cache size
 * there is no point in doing so.
 */
static noinstr void vmx_l1d_flush(struct kvm_vcpu *vcpu)
{
	int size = PAGE_SIZE << L1D_CACHE_ORDER;

	/*
	 * This code is only executed when the flush mode is 'cond' or
	 * 'always'
	 */
	if (static_branch_likely(&vmx_l1d_flush_cond)) {
		bool flush_l1d;

		/*
		 * Clear the per-vcpu flush bit, it gets set again
		 * either from vcpu_run() or from one of the unsafe
		 * VMEXIT handlers.
		 */
		flush_l1d = vcpu->arch.l1tf_flush_l1d;
		vcpu->arch.l1tf_flush_l1d = false;

		/*
		 * Clear the per-cpu flush bit, it gets set again from
		 * the interrupt handlers.
		 */
		flush_l1d |= kvm_get_cpu_l1tf_flush_l1d();
		kvm_clear_cpu_l1tf_flush_l1d();

		if (!flush_l1d)
			return;
	}

	vcpu->stat.l1d_flush++;

	if (static_cpu_has(X86_FEATURE_FLUSH_L1D)) {
		native_wrmsrl(MSR_IA32_FLUSH_CMD, L1D_FLUSH);
		return;
	}

	asm volatile(
		/* First ensure the pages are in the TLB */
		"xorl	%%eax, %%eax\n"
		".Lpopulate_tlb:\n\t"
		"movzbl	(%[flush_pages], %%" _ASM_AX "), %%ecx\n\t"
		"addl	$4096, %%eax\n\t"
		"cmpl	%%eax, %[size]\n\t"
		"jne	.Lpopulate_tlb\n\t"
		"xorl	%%eax, %%eax\n\t"
		"cpuid\n\t"
		/* Now fill the cache */
		"xorl	%%eax, %%eax\n"
		".Lfill_cache:\n"
		"movzbl	(%[flush_pages], %%" _ASM_AX "), %%ecx\n\t"
		"addl	$64, %%eax\n\t"
		"cmpl	%%eax, %[size]\n\t"
		"jne	.Lfill_cache\n\t"
		"lfence\n"
		:: [flush_pages] "r" (vmx_l1d_flush_pages),
		    [size] "r" (size)
		: "eax", "ebx", "ecx", "edx");
}

static void vmx_update_cr8_intercept(struct kvm_vcpu *vcpu, int tpr, int irr)
{
	struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
	int tpr_threshold;

	if (is_guest_mode(vcpu) &&
		nested_cpu_has(vmcs12, CPU_BASED_TPR_SHADOW))
		return;

	tpr_threshold = (irr == -1 || tpr < irr) ? 0 : irr;
	if (is_guest_mode(vcpu))
		to_vmx(vcpu)->nested.l1_tpr_threshold = tpr_threshold;
	else
		vmcs_write32(TPR_THRESHOLD, tpr_threshold);
}

void vmx_set_virtual_apic_mode(struct kvm_vcpu *vcpu)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	u32 sec_exec_control;

	if (!lapic_in_kernel(vcpu))
		return;

	if (!flexpriority_enabled &&
	    !cpu_has_vmx_virtualize_x2apic_mode())
		return;

	/* Postpone execution until vmcs01 is the current VMCS. */
	if (is_guest_mode(vcpu)) {
		vmx->nested.change_vmcs01_virtual_apic_mode = true;
		return;
	}

	sec_exec_control = secondary_exec_controls_get(vmx);
	sec_exec_control &= ~(SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES |
			      SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE);

	switch (kvm_get_apic_mode(vcpu)) {
	case LAPIC_MODE_INVALID:
		WARN_ONCE(true, "Invalid local APIC state");
		break;
	case LAPIC_MODE_DISABLED:
		break;
	case LAPIC_MODE_XAPIC:
		if (flexpriority_enabled) {
			sec_exec_control |=
				SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES;
			kvm_make_request(KVM_REQ_APIC_PAGE_RELOAD, vcpu);

			/*
			 * Flush the TLB, reloading the APIC access page will
			 * only do so if its physical address has changed, but
			 * the guest may have inserted a non-APIC mapping into
			 * the TLB while the APIC access page was disabled.
			 */
			kvm_make_request(KVM_REQ_TLB_FLUSH_CURRENT, vcpu);
		}
		break;
	case LAPIC_MODE_X2APIC:
		if (cpu_has_vmx_virtualize_x2apic_mode())
			sec_exec_control |=
				SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE;
		break;
	}
	secondary_exec_controls_set(vmx, sec_exec_control);

	vmx_update_msr_bitmap_x2apic(vcpu);
}

static void vmx_set_apic_access_page_addr(struct kvm_vcpu *vcpu)
{
	const gfn_t gfn = APIC_DEFAULT_PHYS_BASE >> PAGE_SHIFT;
	struct kvm *kvm = vcpu->kvm;
	struct kvm_memslots *slots = kvm_memslots(kvm);
	struct kvm_memory_slot *slot;
	unsigned long mmu_seq;
	kvm_pfn_t pfn;

	/* Defer reload until vmcs01 is the current VMCS. */
	if (is_guest_mode(vcpu)) {
		to_vmx(vcpu)->nested.reload_vmcs01_apic_access_page = true;
		return;
	}

	if (!(secondary_exec_controls_get(to_vmx(vcpu)) &
	    SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES))
		return;

	/*
	 * Grab the memslot so that the hva lookup for the mmu_notifier retry
	 * is guaranteed to use the same memslot as the pfn lookup, i.e. rely
	 * on the pfn lookup's validation of the memslot to ensure a valid hva
	 * is used for the retry check.
	 */
	slot = id_to_memslot(slots, APIC_ACCESS_PAGE_PRIVATE_MEMSLOT);
	if (!slot || slot->flags & KVM_MEMSLOT_INVALID)
		return;

	/*
	 * Ensure that the mmu_notifier sequence count is read before KVM
	 * retrieves the pfn from the primary MMU.  Note, the memslot is
	 * protected by SRCU, not the mmu_notifier.  Pairs with the smp_wmb()
	 * in kvm_mmu_invalidate_end().
	 */
	mmu_seq = kvm->mmu_invalidate_seq;
	smp_rmb();

	/*
	 * No need to retry if the memslot does not exist or is invalid.  KVM
	 * controls the APIC-access page memslot, and only deletes the memslot
	 * if APICv is permanently inhibited, i.e. the memslot won't reappear.
	 */
	pfn = gfn_to_pfn_memslot(slot, gfn);
	if (is_error_noslot_pfn(pfn))
		return;

	read_lock(&vcpu->kvm->mmu_lock);
	if (mmu_invalidate_retry_hva(kvm, mmu_seq,
				     gfn_to_hva_memslot(slot, gfn))) {
		kvm_make_request(KVM_REQ_APIC_PAGE_RELOAD, vcpu);
		read_unlock(&vcpu->kvm->mmu_lock);
		goto out;
	}

	vmcs_write64(APIC_ACCESS_ADDR, pfn_to_hpa(pfn));
	read_unlock(&vcpu->kvm->mmu_lock);

	/*
	 * No need for a manual TLB flush at this point, KVM has already done a
	 * flush if there were SPTEs pointing at the previous page.
	 */
out:
	/*
	 * Do not pin apic access page in memory, the MMU notifier
	 * will call us again if it is migrated or swapped out.
	 */
	kvm_release_pfn_clean(pfn);
}

static void vmx_hwapic_isr_update(int max_isr)
{
	u16 status;
	u8 old;

	if (max_isr == -1)
		max_isr = 0;

	status = vmcs_read16(GUEST_INTR_STATUS);
	old = status >> 8;
	if (max_isr != old) {
		status &= 0xff;
		status |= max_isr << 8;
		vmcs_write16(GUEST_INTR_STATUS, status);
	}
}

static void vmx_set_rvi(int vector)
{
	u16 status;
	u8 old;

	if (vector == -1)
		vector = 0;

	status = vmcs_read16(GUEST_INTR_STATUS);
	old = (u8)status & 0xff;
	if ((u8)vector != old) {
		status &= ~0xff;
		status |= (u8)vector;
		vmcs_write16(GUEST_INTR_STATUS, status);
	}
}

static void vmx_hwapic_irr_update(struct kvm_vcpu *vcpu, int max_irr)
{
	/*
	 * Wh